Citation
Development process for improving irrigation water management on farms

Material Information

Title:
Development process for improving irrigation water management on farms
Series Title:
Water management technical report
Creator:
Skogerboe, Gaylord V.
Lowdermilk, Max K.
Sparling, Edward W.
Hautaluoma, Jacob E
Colorado State University -- Water Management Research Project.
Place of Publication:
Fort Collins Colo
Publisher:
Water Management Research Project, Engineering Research Center, Colorado State University
Publication Date:
Language:
English
Physical Description:
4 v. : ill. ; 28 cm.

Subjects

Subjects / Keywords:
Water resources development -- Developing countries ( lcsh )
Irrigation -- Developing countries ( lcsh )
Genre:
bibliography ( marcgt )
non-fiction ( marcgt )

Notes

Bibliography:
Includes bibliographical references.
General Note:
"Prepared under support of United States Agency for International Development, Contract AID/ta-C-1411."
Funding:
Electronic resources created as part of a prototype UF Institutional Repository and Faculty Papers project by the University of Florida.
Statement of Responsibility:
prepared by Gaylord V. Skogerboe ... [et al.].

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University of Florida
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University of Florida
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The University of Florida George A. Smathers Libraries respect the intellectual property rights of others and do not claim any copyright interest in this item. This item may be protected by copyright but is made available here under a claim of fair use (17 U.S.C. §107) for non-profit research and educational purposes. Users of this work have responsibility for determining copyright status prior to reusing, publishing or reproducing this item for purposes other than what is allowed by fair use or other copyright exemptions. Any reuse of this item in excess of fair use or other copyright exemptions requires permission of the copyright holder. The Smathers Libraries would like to learn more about this item and invite individuals or organizations to contact Digital Services (UFDC@uflib.ufl.edu) with any additional information they can provide.
Resource Identifier:
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Full Text









































pment Process for Improving Irrigation Water Management on Farms

PROBLEM IDENTIFICATION MANUAL



Prepared by
Water Management Research Project Staff Water Management Technical Report No. 65B








Development Process for Improving
Irrigation Water Management on Farms



PROBLEM IDENTIFICATION MANUAL


WATER MANAGEMENT TECHNICAL REPORT NO. 65B

Prepared under support of
United States Agency for International Development
Contract AID/ta-C-1411
All reported opinions, conclusions or
recommendations are those of the
authors and not those of the funding
agency or the United States Government.




Prepared by

Max K. Lowdermilk William T. Franklin
James J. Layton
George E. Radosevich Gaylord V. Skogerboe
Edward W. Sparling William G. Stewart

















Water Management Research Project
Engineering Research Center
Colorado State University
Fort Collins, Colorado 80523

March 1980








PROBLEM IDENTIFICATION MANUAL


PREFACE


This manual is designed as a resource for identification of farm system constraints on irrigated agriculture. Information contained in this manual will provide a means for determining what components of the system are not functioning adequately to achieve improved crop production goals. The farm water management system, the focus of this manual, has strong interrelationships with various subsystems. As
shown in the idealized description of a farm irrigation system (Figure 1), definite physical boundaries are delineated. The first major boundary is the canal itself which is linked to the total irrigation system including storage, diversion, and drainage facilities. The drainage system is another physical boundary that demarcates the farm irrigation system. Within the farm system there are physical boundaries including conveyance channels, farm fields, irrigation basins, and drainage ditches.
The farm irrigation system is also an open system since it is linked with not only the larger physical irrigation system, but with many organizations that regulate it and supply essential inputs. These
organizations include irrigation and agricultural bureaucracies, and private and public organizations that supply essential inputs such as credit, fertilizer, insecticides, seed, and farm equipment. Institutional linkages also include markets and policy-oriented agencies.
The farm irrigation system is man-made. Irrigation is one of the most significant ways man manipulates physical and human resources to increase crop production. The purpose of the farm system is to
provide an adequate physical, chemical, and organizational environment for the production of crops to meet basic human needs. In arid and semi-arid climates, irrigation is usually required to grow crops, and on-farm water management is often the greatest constraint to increased agricultural productivity.
This manual provides a systematic set of procedures for describing and analyzing the system in relationship to this purpose. A description




ii









Canal

WtrSupply and Removal jPlant Environment
Supply ratesTeprte
ConveyanceClmt
Quality of water Tpgah
Water removal Si hsclcniin
Precipitation Biological factors
Salinity Soil chemical factors
Waterlogging Insect and weed control
Rodent-animal protection Natural hazards









IFarm Management Practices _ag hanl
Cropping patterns ITa__CBiologica factorse
Irrigation~Soi chemicals factors--- -Crop inputs IInstitutional Linkaes
Harvesting
Sto eRules and regulations
Natralhazrd




Farm ~ ~ ~ ~ ~ ~ ~ rc MaaeetPatcsoliny hnn
CrpMarket es

r ingRevenue payments
Application rates Markets Extension
Water use Roads-transportation Cooperation
Input services Information networks
Credit Social norms
Water law

Figure 1. Idealized sketch of a farm irrigation system.








of the system and its operation is developed initially from quantitative measurements defining the operational parameters of each of the four major subsystems. These subsystems include the plant environment, farm management practices, water supply and removal, and the institutional linkages as shown in Figure 1.
Several specialists are involved in analyzing the farm system. The engineer measures the efficiency of water distribution, adequacy of volume and rate of water supply, water use, water removal, water dependability, and other aspects. The agronomist is concerned with all the factors that influence the plant environment and measures these factors in relationship to their impact on crop yields. The economist identifies the levels of resource input and output for crop production and farm income. The sociologist identifies the decision-making processes of the farm manager and social factors such as behavior norms, institutional restraints, knowledge status, and information transfer processes that influence farmer decision-making. The perspectives and methods of each discipline are utilized cooperatively to establish a quantitative and qualitative description of each of the four major subsystems and the total operation of the farm water management system.
Information presented in this manual is designed around the four major subsystems: the plant environment, farm management practices, water supply and removal, and institutional linkages. Additionally,
Chapter I provides a description of the manual and its use. Chapter II discusses problem identification. Chapters III through VI provide field procedures for describing and identifying problems in each of the four subsystems. Chapter VII discusses the analyses applied to the data collected under the four subsystems and the interpretation of these analyses.












iv









Development Process for Improving
Irrigation Water Management on Farms



PROBLEM IDENTIFICATION MANUAL


ABSTRACT


Problem Identification is the first of three phases in the
development process with the other phases being the Development of Solutions and Project Implementation. The Problem Identification phase consists of two subphases; namely, Reconnaissance and Problem Diagnosis. The Reconnaissance subphase consists of: setting preliminary program objectives; developing a general overview of the irrigation system; conducting reconnaissance field investigations of the plant environment, farm management practices, water supply and removal, and institutional linkages; preparing a preliminary listing of problems; and refining the program objectives. The Problem Diagnosis subphase consists of: designing diagnostic studies; conducting. diagnostic field studies; analyzing and interpreting the findings; identifying criteria for the selection and ranking of problems according to program objectives; and reporting findings of priority problems and their apparent causes.






















v








TABLE OF CONTENTS


Page
CHAPTER I, DESCRIPTION AND USE OF THE MANUAL . . 1
ORIGIN OF THE MANUAL 2
NEED FOR PROBLEM IDENTIFICATION . . . . . 3
STRUCTURE OF MANUAL . . . . . . . . 4
GLOSSARY OF IMPORTANT TERMS . . . . . . 5
CHAPTER II, THE PROBLEM IDENTIFICATION PROCESS . . 10
PURPOSE AND OBJECTIVES 10
RATIONALE 10
MAJOR BENEFITS 12
CONCEPTS IN THE PROBLEM IDENTIFICATION
APPROACH . . . . . . . . . . . 13
Systematic Approach . .13 Management Approach . . . . . . . . 14
Interdisciplinary Approach . . . . . . . 16
On-Farm Client Focus . 18 Barriers to Problem Identification . . . . . 19
THE PROCESS . . . . . . . . . . . 20
Sequence of Major Activities . . . . . . 20
Setting Preliminary Objectives . . . . . . 20
Reconnaissance Overview of the System . . . . 22 Preliminary Listing of Problems . . . . . . 23
Refining Objectives. 24 Designing Diagnostic Studies . . . . . . 25
Conducting Diagnostic Field Studies . . . . 25 Data Analyses and Interpretation . . . . . 28
Criteria for Ranking Priority Problems . . . . 31 Reporting the Findings . . . . . . . . 32
CHAPTER III, THE PLANT ENVIRONMENT . . . . . 34
CROPS AND CROPPING PATTERNS . . . . . . 34
Crop Inventory . . . . . . . . . . 36
Crop Stands .36 Crop Damage .37 Potential and Actual Yields . . . . . . . 37
Crop Quality and Nutritional Value . . . . . 37


vi









TABLE OF CONTENTS
(continued)

Page
SOILS . 37
Soil Nutrient Supply. 37 Visual Observations. . . . .38 Tissue Tests . .40 Paint and Spray Tests . 42 Imbalances and Toxicity . .42 Chemical Soil Tests. 42 General Fertility Guidelines . . . . . . . 42
Plant Analyses . .43
Physical and Chemical Properties of
Soil and Root Zone . .43
Subsoil Properties . 44 Topography . . . . . . . . . . 44
CLIMATE .44 CHECKLISTS 44
INTERDEPENDENCY OF PLANT ENVIRONMENT WITH
FARM MANAGEMENT PRACTICES . . . . . . 50
Case Study. 50 CHAPTER IV, FARM MANAGEMENT PRACTICES . . . . 53
IRRIGATION PRACTICES .53
Farm Water Use Efficiency . . . . . . . 55
Crop Water Use . 59 Open-Pan Evaporation . . . . . . . . 60
Other Devices for Measurement of
Evaporation . 60
Calculation from Weather Observation
Data . .60
Lysimeters . 61
Irrigation Timing . 61
Field Observations. .61
Calculations of ETp and ETa from
Existing Data. . . .64
Field Measurements. . 64
Tensiometers, Gypsum Blocks, or
Fiberglass Blocks. . 64

vii








TABLE OF CONTENTS
(continued)

Page
Gravimetric and Neutron Probe
Moisture Measurements . . . . . . 64
Irrigation Timing as a Function
of ET Estimates . 65
CROPPING PRACTICES 65
Cropping Patterns . . . . . . . . . 65
Crop Rotation . 65 Crop Mixes . 65 Polyculture . . .65
FARM BUDGETS . . . . . . . . . . . 68
Farm Management Inventory . . . . . . 68
Resource Inventory. .68 Land . . . . 68 Labor 78 Capital. 78 Animals 78 Water Inventory . .78 Outputs .78 Decision-Making Environment . . . . . . 79
Interdependency with Farmer's Community . . . 79
INTERDEPENDENCY OF FARM MANAGEMENT PRACTICES
WITH WATER SUPPLY AND REMOVAL SUBSYSTEMS . 79
CHAPTER V, WATER SUPPLY AND REMOVAL . . . . 81
CLIMATE 81
Climatic Data . .81
Solar Radiation . .81 Air Temperature . 83 Relative Humidity . . . . . . . . 83
Wind Speed .84 Open-Pan Evaporation . . . . . . . 84
Rainfall and Distribution . . . . . . 84
Weather Observation Stations . . . . . . 84
Water Supply Problems . . . . . . 84



viii









TABLE OF CONTENTS
(continued)

Page
Ground Water Recharge Problems . . . . 85 Irrigation Requirements . . . . . . 85
Crop Adaptation Problems . . . . . . 85
Climatic Hazards . 86 WATER AND SALT BUDGETS .86
IRRIGATION WATER . . . . . . . . 88
Source and Availability . . . . . . . . 88
Precipitation. . .s88
Surface Flows, Reservoirs, and
Dams 89
Groundwater Pumpage and Recharge . . . 89
Water Quality. .90
Existing Water Quality Data . . . . . 91
Field Spot-Checks . 91 Individual Sample Analyses . . . . . .91
Silt Burden . . . . . . . . . 91
Mineral Ion Content (TDS) . . . . . 91
Polluted Water . . . . . . . . . 92
Composited Samples . .92 Water Suitability for Irrigation . . . . . 92 COMMAND AREA .92
Topography 93 Land Capability 93 Cropping Patterns . 93 Field Size and Levelness . .94 Location of General Features . . . . . . 94
WATER REMOVAL . 95
Root Zone Salt Balance . . . . . . . . 95
Aeration Requirements . . . . . . . . 96
Workability of Lands . .97 Sources of Drainage Water . . . . . . . 98
Evidence of Drainage Problems . . . . . . 98
CHECKLISTS . 99


ix








TABLE OF CONTENTS
(continued)

Page
INTERDEPENDENCY OF WATER SUPPLY AND
REMOVAL SUBSYSTEMS WITH INSTITUTIONAL
INFRASTRUCTURE . . . . . . . . . 99
CHAPTER VI, INSTITUTIONAL LINKAGES . . . . . 105
WATER IRRIGATION LINKAGES . . . . . . . 105
Policies . 105 Laws, Codes, and Regulations . . . . . . 105
Organizations. 107 Linkages 107
AGRICULTURAL INFRASTRUCTURE . . . . . . 107
Agriculture and Water Organization . . . . . 108 Research and Extension . 108 Agricultural Input Services . . . . . . . 109
Marketing and Transportation . . . . . . 109
Credit Institutions . 110 Cooperatives . .110 Communication and Information Networks . . . 110 Farmer Perceptions of Institutions . . . . .111
SOCIO-CULTURAL NETWORK . . . . . . . .111
The Setting for Social Control . . . . . . 114
Territoriality . 114 Size. .114 Time 114 Facilities . .114
Elements for Social Action . . . . . . . 114
Cultural Elements . 114 Norms .115 Sanctions. .115 Beliefs 115 Sentiments . .115 Goals . . . . . . . . . . 116
Structural Elements . . . . . . . 116
Status-Role. 116


x









TABLE OF CONTENTS
(continued)

Page

Characteristics of the
individual .*.*.*.*. .116 Capacity of the individual . . . . 116
Processes for Social Action . . . . . . . 116
Communication. .117
Boundary Maintenance . . . . . . . 117
Systemic Linkage 117 Social Control . . . . . . 117
The Resulting Social Action . . . . . . 117
Individual Decision-Making
Environment . . . . . .118
The Collective Decision-Making
Environment . . . . . .118
Format for Irrigation Studies . . . . .119
SUMMARY . . . . . . . . 119
CHAPTER VII, DATA ANALYSES AND INTERPRETATION . . 126
INTERDEPENDENCE OF SYSTEM COMPONENTS . . . 126
PROBLEM DIAGNOSIS ANALYSES . . . . 129
Plant Environment . . . . . .131
Farm Management Practices . . . . . 131
Irrigation Practices . . . . . .131
Farm Budgets . . . . . . . 135
Water Supply and Removal . . . . . .136
Climatic Analysis . . . . . . .136
Water and Salt Budgets . . . . 139 Cropland Diversions . . . . .141
Root-Zone Flows . . . . . . 141
Groundwater Model . . . . . .145
Available Models . . . . . . 147
Institutional Linkages . . . . . . I 147
INTERPRETATION OF FINDINGS . . . . . . 148
COMPLETION OF PROBLEM IDENTIFICATION PHASE . . 148




xi









TABLE OF CONTENTS
(continued)

Page
REFERENCES . .151 APPENDICES . .156
EQUIPMENT NEEDS. .157 DATA MANAGEMENT AIDS . . . . . . . 160
SELECTION, TRAINING, AND EVALUATION OF
FIELD WORKERS . .166
EXAMPLE FORMS FOR FARM BUDGET ANALYSIS . 178









































xii









LIST OF FIGURES


Figure Page
1 Idealized sketch of a farm irrigation system .iii
2 Diagram showing the farm level learning dimensions
of researchers and farmers . . . . . . 19
3 Flow diagram of sequential activities in the Problem
Identification phase. 21
4 Idealized sketch of the plant environment . . . 35
5 Idealized sketch of a farm irrigation system and
farm management practices . . . . . . 54
6 Schematic of instrumentation required for on-farm
hydrology investigations . . . . . . . 56
7 Schematic of the hydrologic variables to be
considered in an on-farm subsystem investigation 57
8 Schematic of constant water-table lysimeter . . . 62
9 Schematic of the construction of a hydraulic
weighing lysimeter .63
10 Example of agricultural land use mapping . . . 66
11 Idealized sketch of a farm irrigation water supply
and removal subsystem 82 12 Idealized sketch of the institutional infrastructure
for a farm irrigation system . . . . . . 106
13 Flow diagram for data analyses and interpretation
of findings .127 14 Interdependence of irrigation system components
and program objectives . . . . . . . 128
15 Factors affecting levels of living of farmer clients . 128
16 Flow diagram for Problem Diagnosis analyses . . 130
17 Procedure for the evaluation and improvement of
irrigation systems. .132 18 Categories of irrigation performance for individual
application .134 19 Example of monthly and annual frequency distribution
for precipitation and temperature . . . . . 137 20 Comparison of lysimeter data and the Penman equation
estimate for alfalfa in 1975 . .140 21 Schematic of a generalized hydro-salinity model . 142
22 Illustrative flow chart of the root-zone budgeting
procedure 144




xiii









LIST OF FIGURES
(continued)


Figure Page
23 Flow chart of the groundwater modeling
procedure 146
24 Interpretation of findings from the Problem Diagnosis
analyses .149













































xiv









LIST OF TABLES


Table Page
1 Glossary of terms 6
2 Checklist of problem identification activities for use
by the program team manager . . . . . 15
3 Basic requirements for successful teamwork . . . 17
4 Activities checklist for designing problem
identification (P.I.) studies . . . . . . 26
5 Outline of selected types of data collected by one
discipline and utilized by another discipline . . 29
6 Criteria for ranking priority problems . . . . 31
7 General fertility guidelines for some nutrients . . 43
8 Checklists on reconnaissance methods for crops and
cropping patterns and soils . . . . . . 45
9 Checklists on detailed diagnostic methods for crops
and cropping patterns and soils . . . . . 48
10 Hypothetical case study of symptoms and causes of
nitrogen deficiency . . . . . . . . 51
11 Definitions of cropping intensity . . . . . 67
12 Format for inventories of actual practices for major
crops 69
13 Checklists on reconnaissance inventory for farm
management practices . . . . . . . 71
14 Checklists on detailed diagnostic methods for farm
management practices . . . . . . . 74
15 Checklists on reconnaissance methods for water
supply and removal . . . . . . . . 100
16 Checklists on detailed daignostic methods for water
supply and removal. .102
17 Major organizations related to water supply and
removal 104
18 Format of major sociological categories affecting the
decision-making process of individuals . . . 113 19 Format of sociological components affecting the
irrigation behavior of a farmer . . . . . 121
20 Checklists on reconnaissance methods for
institutional linkages 122 21 Checklists on detailed diagnostic methods for
institutional linkages 124




xv








CHAPTER I


DESCRIPTION AND USE OF THE MANUAL


This manual is designed to provide a flexible set of guidelines, concepts, procedures, and methods for identification of factors that may inhibit efficient functioning of farm irrigation systems. Procedures are provided for a systematic approach to objective evaluation of existing farm irrigation systems. This is done as preparation for a systematic search for socio-technical solutions to problems that may occur.
The authors have extensive experience in research and development related to irrigation systems, and are well aware that irrigation systems have unique physical, social, economic, and legal characteristics that have complex interdependencies. While irrigation systems have many "site-specific" factors that must be analyzed individually, there are procedures that can be utilized for understanding general problems.
This manual provides several aspects that should be considered in evaluating a farm irrigation system. The factors and methods of investigation described can serve as a checklist to emphasize important variables that may require systematic examination if adequate data do not already exist. This manual is designed to provide guidance in developing an understanding of water management constraints in irrigated agriculture.
The flexible systematic approach for evaluating existing farm irrigation systems explained in this manual will help delineate priority research needs and improvements. A major assumption is that all
irrigation systems can be greatly improved in terms of efficiency and increased benefits to farmer-clients. However, there are several aspects that will not be covered in this manual. This manual DOES NOT PROPOSE:

To provide a universal technique that can be used without
adaptation to specific situations.

To provide guidelines to study problems that are simply
interesting to the particular investigators.

To provide a guide for the identification of all problems of
any irrigation system.






2

To provide guidance for surveys that are so comprehensive
they are of little use to applied researchers and practitioners.

To assume to do more than serve as a flexible guide to
practitioners and researchers who have the task of improving
complex farm irrigation systems.


ORIGIN OF THE MANUAL

The authors have intensively studied their own assumptions and approaches regarding irrigation systems. They have determined there is a need for using a more objective and systematic approach. Their approach was field tested in Pakistan with respect to research and development activities. A theoretical framework, A Research1
Development Process for Improvement of On-Farm Water Management
has been developed and should be consulted by the reader.
This manual of procedures and methods is the first phase of a much larger team effort in describing the development process for improving irrigation water management on farms. Manuals have been prepared to provide procedural guides for each of the three phases:

I. Problem Identification

This combines an interdisciplinary approach with farmer participation to achieve an understanding of system operation.
Results of this method are an objective, quantitative definition
of priority problems

II. Development of Solutions

The interdisciplinary staff combines knowledge and experience with systematic research to develop acceptable solutions to priority problems. Applied, adaptive, and evaluative research methods are also used under farmer conditions for the assessment of solutions. These results are used to define
solution packages.


IClyma, Wayne; Max K. Lowdermilk; Gilbert L. Corey, 1977. A
Research-Development Process for On-Farm Water Management. Water
Management Technical Report No. 47, Colorado State University, Fort Collins.
2William Franklin and William Stewart, Agronomy; Gaylord Skogerboe and Doral Kemper, Engineering; Ed Sparling, George Radosevich, and Warren Smith, Economics; Max Lowdermilk, Dave Freeman, and James Layton, Sociology; and Jack Hautaluoma, Psychology.
3
op. cit. p. 8.





3

III. Project Implementation

A development project evolves when decision-makers select a solution package for implementation. Trained personnel use the carefully designed technological package to work directly
with farmers to solve their problems.


NEED FOR PROBLEM IDENTIFICATION

Those concerned with improving farm irrigation systems around the world should not have to be convinced of the need to identify problems systematically. In the past, however, many problems have usually been identified in this manner.
Financial resources are now being allocated to solving the problems of irrigation water management. Previously, few systematic approaches to evaluate existing irrigation systems, analyze weaknesses and failures, and prescribe technologies for improvement were developed. Usually, each system that was evaluated became an individual case study. Improvement programs were developed within a short time period utilizing little more than the experience of the project leader. Frequently, these improvements treated symptoms rather than real problems. Such conventional approaches generally ignore the farmer, his attitudes, his knowledge, and his constraints. Previous approaches have not resulted in sufficient significant improvements at the farm level.4
Water management improvement is important because there are an estimated 200 million acres of land presently under irrigation. New areas are being added at the rate of less than 10 million acres annually. Many irrigation systems operate at relatively low levels of water use efficiency and at low levels of production.5 Thus, a major need is for the improvement of existing systems for the following reasons:

To conserve water supplies by improved management for rapid
increases in food production;

To improve the return on investments of existing systems;


4Wiener, Aaron. 1972. The Role of Water in Development. McGraw-Hill Book Co., New York, p. 422.
5Bos, M. G. and Nugteren, J. 1974. International Institute on Irrigation Efficiencies, Pub. No. 19, International Institute for Land Reclamation and Improvement, Wageningen, The Netherlands.






4

To reduce the costly waterlogging and salinity problems that
are often symptoms of poor management;

To identify the methods small farmers can use to increase net
agricultural productivity by participating in new production
possibilities;

To reduce the need for large capital investments in new
systems; and

To gain knowledge that can provide new criteria for the
development and management of other systems with a focus on
participation of farmer-clients.

A concerted effort to improve irrigated agriculture, if focused at helping the subsistence farmer having small landholdings, could bring improved income and living conditions to a substantial percentage of the world's disadvantaged.

The cost of expanding the present 85 million irrigated hectares by 90 million hectares is estimated at $130,000 million. This is not only exceedingly costly, but also a slow process because projects from design to completion often take 10 to 12 years. Investments in new projects will continue but more quick yielding programs seldom improve the efficiency of farm water use, therefore, the focus in the years ahead must be given to farm-level problems. There is much exciting drama in building large structures but we must not forget the small and often tragic dramas that take place daily on millions of small holders' farms where water conservation is a matter
of success and failure and even life and death.6

STRUCTURE OF MANUAL

This manual is designed for quick reference and each chapter is delineated below.
Chapter II answers three basic questions about problem identification. These questions are:

Why do problem identification studies?
What is the problem identification process?
How is problem identification done?

Chapters III through VI provide both reconnaissance procedures and detailed diagnostic methods for the examination of factors related to:

6World Bank, 1975. The Assault on World Poverty, John Hopkins University Press, Baltimore, Maryland, pp. 95-96.





5


The Plant Environment (Chapter III)
Farm Management Practices (Chapter IV)
Water Supply and Removal (Chapter V)
Institutional Linkages (Chapter VI)

In each of the four chapters special factors are discussed along with the suggested reconnaissance and detailed diagnostic procedures and methods for use in field investigations. The most important factors have been included; however, there are likely others that the readers will want to add for their site-specific situation. Checklists are provided at the end of Chapter III through Chapter VI for convenience. The reader is encouraged to utilize this checklist to determine if all essential factors have been covered.
After each major section the factors of one section are related to those of the next section. For example, the last section of Chapter III shows how optimal plant growth factors relate to farm management practices which are the subject of Chapter IV.
Chapter VII provides a description of the interdependence of the four subsystems in a problem identification study, with a focus on the importance of close project staff collaboration. The analyses applied to the data generated from the diagnostic field studies are discussed, along with the interpretation of these analyses.
This is followed with appendices that provide several aids for the field manager including:

Equipment needs;
Data management aids;
Selection, training, and evaluation of field investigators; and
Example forms for farm budget analysis.

In addition to this manual, there is a series of technical field methods published by the Egypt Water Use and Management Project at Colorado State University through funds from the USAID. These are referenced in this text for easy referral by the field workers.


GLOSSARY OF IMPORTANT TERMS

Important concepts and definitions utilized throughout the manual are provided. While there can be much debate about certain





6


definitions, the definitions in Table 1 represent the authors intent when used in these manuals.

Table 1. Glossary of terms.


Term Definition


Action Research A systematic investigation conducted
specifically for a defined program which does not conclude with data collection, but leads eventually to project implementation. Testing is conducted under the conditions of the recipient of the research.

Adaptive Research A systematic investigation to fit new
technological advances into different environments.

Agronomic Subsystem A system that utilizes the resources
of soil, solar energy, and water in combination with necessary inputs to create an adequate environment for the growth of crops of the types and amounts required.

Applied Research The direction or utilization of
knowledge to the improvement or change of specific materials or conditions.

Communication The transmission of thoughts, ideas,
and information from one individual or group to another individual or group.

Conflict Resolution The process where disagreement
among members of the research staff is confronted and a decision is made on how that disagreement will be resolved.

Economic Factors The allocation or utilization of all
physical, chemical, biological,
human, and organizational resources in such a way as to maximize economic and social goals from farm production efforts as determined by individual decision makers and public policy.





7




Evaluative Research The process in which the scientific
method is consciously applied for the purpose of making a judgment about the value of methods, processes, and programs about which there is concern utilizing various types of data, decision rules, and criteria.

Farmer-Client The focus of a research project that
encourages the concentration of the researchers to be centered on the farmers and also develops proper attitudes towards working with farmers.

Farm Water Management Water management in agriculture
is the process by which water is manipulated and used in the production of food and fibers. Water management is how water resources, irrigation facilities laws, farmers, institutions, and procedures in soil and cropping systems are used to provide water for plant growth. It encompasses all water used for that purpose including irrigation and water from natural precipitation.

Interdisciplinary Approach An approach where different
academic disciplines are combined to examine a research problem. The output of the study consists of an integrated approach where each discipline considers the effects of the other disciplines in analysis and recommendations.

Management Focus Recognization by the researchers
that a farmer is a decision-maker, and that the operation of the farm results from a rational approach of identifying a problem, developing alternative solutions and implementing the solution on the farm. Any recommendations by the
research group must be analyzed as to the consequences.





8




Problem Identification The procedure through which the
understanding of an irrigation system is attained in order to define specific shortcomings that prevent the irrigation system from being fully effective in its operation.

Reconnaisance Preliminary observations of an area
which allows researchers to obtain general information to serve as a means for providing an initial direction for research activity.
Research Team Individuals who work together on a
research problem.
Social Subsystem The social and organizational
supports at the macro- and microlevels needed for successful manipulation of the farm irrigation system to achieve desired individual and collective goals over time.
Systems Approach A research approach with the
objective to study all the components pertaining to a specific research problem. With respect to irrigation management, such aspects would include physical and institutional properties.
Team Building The process in which individuals
involved in a research program change from single purpose investigations by each participant to an integrated study involving the contributions of all the participants.

Water Application Process A process to supply desired amounts
of water uniformly to meet the needs of seed germination, plant
emergence, salinity control, soil physical conditions, erosion,
aeration, temperature, and surface drainage in a manner to adequately grow crops.





9




Water Delivery System A system to convey water from the
supply source to the fields to be irrigated at the proper time, volume, and flow rates required for the cropped area considering losses occurring within the system based upon design criteria.

Water Removal System A system to maintain proper salinity
levels, physical soil conditions (for root aeration and workability of soil), and to reduce health and environmental hazards.

Water Use Requirements The adequate supply of water at the
proper times in the quantity and quality necessary for crops to maintain acceptable levels of soil salinity, soil-air temperature, and soil physical conditions for crop growth.






10


CHAPTER II

THE PROBLEM IDENTIFICATION PROCESS

PURPOSE AND OBJECTIVES

The goal of the Problem Identification phase is to understand the traditional farming system and isolate the major constraints that inhibit its adequate functioning. It is assumed the purpose of the system is to increase agricultural production, improve the standard of living for all classes of farmers, and to conserve natural resources. The objectives of the Problem Identification phase are:

1. To provide a systematic approach for understanding the farm
irrigation system,

2. To identify constraints that inhibit agricultural production, 3. To identify constraints that impede the progress of small
operations,

4. To provide output from the Problem Identification phase as
input to the Development of Solutions phase, which requires
more intensive research, and

5. To provide data that can be utilized within a short period of
time (one or two irrigation seasons) depending on the particular conditions and needs of the Problem Identification
phase.


RATIONALE

There are several important reasons why increased attention should be given to problem identification studies of irrigation systems in low income nations. These reasons are listed below:

1. Little is known about the content and structure of traditional
farming systems,

2. Valid empirical farm-level data for systematic planning of
research is typically not available,

3. There is always a danger of treating problem symptoms rather
than causes in dealing with complex farming systems, and

4. Most available research covers a limited subject area that
generally neglects systems problems.





11


In the absence of good problem identification research, agricultural policies and programs are often implemented that place further constraints on improving production possibilities. There have often been pressures to continue solving problems even before the real problems have been identified. Solutions for "assumed problems" are often not acceptable or usable by farmers. In many low income countries there is not an adequate data base to provide policy makers the information needed for rational planning purposes.
Problem identification will reduce the danger of development programs treating symptoms rather than problems. For example, the desalination plant on the Colorado River treats the symptom, salinity, rather than its cause--excessive application of irrigation water. Another example is the costly research and development program in Pakistan to control the twin menaces of waterlogging and salinity.8 Previously, researchers in Pakistan assumed that farm conveyance efficiencies were about 80 to 90 percent without actually measuring losses. When problem identification investigations were conducted, actual efficiencies were found to be only 40 to 50 percent.9
Instead of making assumptions about problems, the researcher should examine the situation carefully in order to understand the farmers' perceptions of the problem. In other words, a complete
analysis is needed to identify the symptoms before solutions are made and specialists are called for assistance.




7Mellor, John, May, 1973. "Developing Science and Technology Systems: Experiences and Lessons from Agriculture." Occasional Paper No. 63, Department of Agricultural Economics, Cornell University. 8This does not mean that the SCARP Program in Pakistan did not greatly reduce waterlogging. They made a substantial contribution, but it was not realized that part of the problem was related to farmers' irrigation practices.
9World Bank, January 28, 1976. Pakistan Special Agriculture Sector
Review. Volume III; Annex on Water Management. This report states that a 1 percent error in the efficiency of the system is equivalent to 1.4 MAF of water. In terms of storage cost of the Tarbella Dam, this error in efficiency is equivocable to $1 billion.





12


Special focus in problem identification is given to listening to the farmer-clients, understanding their needs, and their perceptions of major farm constraints. This procedure helps build credibility with the farmers by increasing their awareness and interest in solving farm problems. Farmers' perceptions often provide useful insights into the problems. Second, without listening to the farmer it is unlikely that one will gain an understanding of how the farming system actually works. If development programs are to be successful, more understanding of how traditional farming systems work is necessary.
The role of the farmer has a central focus in the Problem Identification phase. Basic assumptions made about the farmer are listed.

1. The farmer is central to the irrigation system.

2. The farmer is rational in decision-making with respect to the
constraints.

3. Traditional farmers will respond positively to improved
technologies that are technically sound, economically
profitable, and culturally compatible.

4. Farmers will participate in improvement projects that
demonstrate visible and tangible results if positive and concerted efforts are made to develop credibility by including farmers in the planning and evolution of these programs.


MAJOR BENEFITS

A major benefit derived from the Problem Identification phase is understanding the system as composed of many interdependent factors. Answers must be found for such questions as: What are the system boundaries? What is the system supposed to do? How well does it function? What are the critical components of the system and how do they interact? What components are not functioning adequately? Since the farmer is an important aspect of the system, information must be obtained about what he does, why he does it, and what are the results.
A second benefit is the objective identification of major problems that inhibit increased crop production based on empirical field data. All problems cannot be included; therefore, it is necessary to focus upon significant crop production problems. Stated criteria are used for






13


ranking problems in relationship to their importance in limiting crop production. Both quantitative and qualitative methods of ranking are used.
Other benefits include provision of empirical data for input into the solution phase, provision of data for use in the evaluation of the program, participation of the farmer, procedures for developing and maintaining credibility with farmers, opportunity to train host country personnel in interdisciplinary procedures for problem identification, and saving of time and other scarce resources.
There are always pressures in research and development programs to provide fast results for anxious host. country officials and donors. Time spent in the Problem Identification phase is, time -saved in the 10
Development of Solutions phase, as one researcher has suggested.

Difficulty in isolating the problem is often due to the tendency to spend a minimum of effort on problem definition in order to get on to the important. matter of solving it.
Inadequately defining the problem is a tendency that is downright foolish on an important and extensive problem-solving task. A relatively small time spent in carefully isolating and defining the problem .can be extremely valuable both in illuminating possible simple solutions and in ensuring that a great deal of effort is not spent only to find that the difficulty still
exists--perhaps in greater magnitude.


CONCEPTS IN THE PROBLEM IDENTIFICATION APPROACH

Problem identification is the combination of an interdisciplinary team approach with active farmer involvement to achieve an understanding of how the farm irrigation system operates and to identify in a systematic and objective manner a quantifiable definition of system problems. Clyma, Lowdermilk, and Corey (1977) has a detailed
explanation of this process.


Systematic Approach

The problem identification process is one that is systematic in contrast to a fragmented approach. Because of the complexity of the



10Adams, J. L. 1974. Conceptional Blockbusting; A Guide to Better
Ideas. W. H. Freeman and Co., San Francisco, CA, p. 14.





14


farm irrigation system with its physical, biological, legal, organizational, and social characteristics it is impossible for single researchers to understand adequately or describe the system by focusing on single components, or to identify their interactions. The problem identification approach requires researchers who plan carefully and work closely together to establish preliminary objectives, do field reconnaissance, and design and implement diagnostic field studies. Research efforts must include coverage of the whole farm irrigation system, and not simply those aspects that someone assumes are important (Table 2). Teamwork is highlighted for all major activities and this requires good management if the process of problem
identification is to produce the desired results.


Management Approach

The emphasis throughout this manual is MANagement. This
concept is used in two particular ways. First, the focus and objective of the Problem Identification phase is to ascertain the effectiveness of the management of the present system. This requires understanding
the system from the position of the farmer. Often the complex task of managing all the factors related to the farm system is not fully appreciated. Unlike the specialized roles of individuals in industry, the farmer must perform the role of cultivator, buyer, seller, bookkeeper, along with other functions. The complexity of the farmer's management tasks is shown in Figure 1. It should be noted that some of these
factors can be controlled by the farmer while others cannot be controlled by the farmer. This makes management even more complex and creates extreme risks for the decision-maker.
Researchers should attempt to understand the farmer's situation as they investigate farm problems. This perspective will help the project staff recognize that problems involved in farming systems are multidimensional and require a strong interdisciplinary approach. No one discipline or single researcher can hope to comprehend these complex interrelationships alone; therefore, a group approach is the only reasonable method that will produce results.





15

Table 2. Checklist of problem identification activities for use by the program team manager.

Preparation for Problem Identification Studies
__Selection of investigators Selection of a team leader
Team building training
-_Discipline training in field methodologies Setting of objectives of problem identification studies Gaining an Overview of System
Identification of available research
Discussion with officials from relevant organizations about their view
Obtain maps and other relevant resources
Development of checklists of possible problem areas
Development of lists of other people to contact Organization of Initial Field Visits
Criteria for field sites to visit
Responsibilities of team members for initial field visits
Logistics for initial field visit Implementing Initial Field Visits
Visits to farms
Observation methods for all team members
Nonstructured interviews with farmers and those who work with
farmers directly
Selected measurements
Team collaboration and preparation of preliminary report on initial
field visits
Establish criteria for selection of sample sites for formal problem
identification studies
Design of Detailed Diagnostic Field Studies
Decisions on site selection
Develop objectives for problem identification
Decisions on methodologies
Design and test survey instruments
Design selection criteria for field workers
Establish responsibilities for all field workers
Design evaluation methods for field workers
Develop checklist for equipment needs and logistics
Establish time frame for problem identification studies
Establish data management plans Implement Formal Investigation
Develop required maps
Develop methods for data quality control and field supervision
Collect data
Analyze and interpret data
Write team report on findings
Rewrite report for selected audiences Establish Criteria for Selection
Clarify assumptions used
Clarify quantitative or qualitative methods
Rank problems in terms of criteria





16

This leads to the second dimension of management. Just as the farm manager must coordinate many factors, the manager of individual researchers must know how to manage the staff effectively. Without good management, there is the danger of individual researchers doing what they prefer. Without careful coordination, collaboration, and
communication, it is doubtful if problem identification investigations will result in either an understanding of the complex farm system problems or an identification of the priority problems that require solutions (Table 2 shows some of the activities a group leader must coordinate). The program leader (also called team leader, group leader, team manager, or program manager in this text) is in a position similar to the farm manager. While not directly responsible for each activity listed, the program leader must make decisions about all these factors. However, many of these decisions can be delegated to others. Unlike the farmer who learns through long experience, very few administrators of interdisciplinary research groups have had either long experience or training. Where possible, special training should be obtained.
The sequence of activities in Table 2 is not inflexible; however, the team manager is responsible for their execution. This guide or
checklist can be used by the manager to direct all staff to a systematic approach in the Problem Identification phase.


Interdisciplinary Approach

Problem identification requires an effective interdisciplinary research staff to understand the farm irrigation system. Along with technically qualified, experienced professionals in the disciplines required, other essential components are commitment to the project, management skills, open communication, and close collaboration of team members with each other and with the farmers. Perhaps the three most essential elements for effective interdisciplinary teamwork along with expertise include respect for the contributions that each discipline can make; desire to establish effective communication with all disciplines and farmers; and the desire to learn from each other and from farmers in particular.
Ideal requirements for successful teamwork is listed in Table 3. It may seem impossible to find experts with these qualifications. However,





17



Table 3. Basic requirements for successful teanwork.



Requisites Checklist of Attributes

Commitment Expertise in discipline
Broad training and experience Respect for contributions of other disciplines Flexibility
Emotionally mature and secure Demonstrated ability to work well on teams
Committed to interdisciplinary research
Commitment to farmer-cients Willingness to learn

Management Demonstrated management abilities
Skills in program planning Skills in conflict resolution Skills in task assignments Gives attention to detail Ability to communicate Does not favor a single discipline Evaluation skills Ability to communicate and skills in human relations Incentive system design

Communication Open communication, no hidden
agenda
Regular staff meetings for planning Communication feedback utilized Communication to and from clients Communication to and from all team members
Communication to and from officials

Collaboration Goal setting
Developing a framework and design of study
_Agreement on methodologies Selection of sample Problem-solving Evaluation of work Data management plans Analysis of data and reporting





18

this ideal list provides goals that can be obtained over time if the staff are willing to communicate, learn, and appreciate each other and their disciplines.


On-Farm Client Focus

The problem identification approach, unlike many research approaches, provides strong focus on the farmer and the farm system. Actions in any portion of the Problem Identification phase are developed from farm level data without prior assumptions about farm problems. Assumptions too often dictate research and development efforts.
The Hadith, one of the Holy Books of Islam, for example, provides a significant statement about learning that relates to problem identification studies at the farm level. It is translated as "if there is knowledge in China, go there and learn." The authors of this manual are saying to all researchers, "there is knowledge at the farm level and from the farmer; go there and learn how the farm irrigation system works." To use an arabic term to stress the point, a true Talib Elm (Arabic for "seeker after knowledge"), will search for knowledge at the farm level and from the farmer and not try to find an easy way out. This strong focus on farm level conditions and the farmer-client is an important concept for problem identification studies.
Problem Identification should be viewed as a learning experience. A simple diagram emphasizing mutual learning on the part of the farmer and the researcher is presented in Figure 2. Unless the environments of the researcher and the farmer are properly linked, learning is inhibited. Unless the research situation is geared to the real farm situation, it is unlikely that the farmer can be significantly helped by researchers.
The analogy of the doctor-patient can also be used to indicate the importance of mutual learning. The doctor (researcher) examines the physical condition and asks significant questions of the patient (farmer) in order to understand his particular situation. The farmer provides knowledge of his condition in order that a diagnosis is possible. The researcher then provides the farmer with knowledge drawn from his diagnostic skills to assist the client. If this analogy is accepted as basic to the Problem Identification phase, then the general principles listed below should prevail throughout the process.





19


Environment Communication Environment
S ao. Understanding Fa rm
Knowledge Knowledge
and Mutual Learning and
Experience Experience




Figure 2. Diagram showing the farm level learning dimensions of
researchers and farmers.

1. Problem Identification should include all disciplines required,
as well ,as farmer-clients to assure that a systems approach is
utilized.

2. Problem Identification should be task-oriented, rather than
oriented toward prestige maintenance of one discipline over another. Each discipline is necessary and one discipline is no
more important than another.

3. Problem Identification should be educational for researchers
and clients and lead to greater understanding of the farm
system and its subsystems.

4. Problem Identification should be experimental in that it is
never final in the research and development process. At
stages other than problem identification, the researchers may
have to search for sources of problems ignored earlier.

Barriers to Problem Identification

There are several barriers that cause researchers to disregard the basic learning model of the Problem Identification phase. These barriers have been identified often by observation of researchers at work. These are as follows:

1. Inability to see the farming community as a system,

2. Inconsistency of the researcher's image of how the system
should work with how it actually does,

3. Lack of interaction and communication among researchers in
planning for problem identification,
4. Impatience in identifying the real problems first before
solutions are determined,

5. Inability to appreciate contributions from other disciplines,






20


6. Assumption that the "expert" should know what the problem
is and how to solve it without verification in a specific field
situation,

7. Lack of appreciation of the local culture which clients have
acquired and lack of acceptance of the clients' role in
decision-making,

8. Assumption that development problems can be solved quickly
by applying more technology without considering the social
factors, and

9. The lack of understanding and sensitivity to cross-cultural
differences that exist between researchers and farmers and
among farmer-clients.


THE PROCESS OF PROBLEM IDENTIFICATION To accomplish problem identification it is necessary to understand the sequence of major activities including reconnaissance field investigations, designing diagnostic studies, conducting diagnostic field studies, analyzing and interpreting findings, and selecting criteria for ranking significant problems.


Sequence of Major Activities

The systematic approach of the Problem Identification phase includes some overlap of activities. This does not mean, however, that activities are random or to be conducted as separate procedures. Experience indicates there is a general sequence of events that can be delineated. The sequence of the major activities that can be used for problem identification studies is shown in Figure 3.


Setting Preliminary Objectives

First, there is a need for clearly stated preliminary objectives. The preliminary objectives may, for example, be similar to the following:

1. To gain an understanding of how the organization of the
system and the conditions of the situation influence farm
decisions,

2. To identify the major physical, biological, socioeconomic, and
organizational constraints in the farm system that limit
agricultural production, and





21


PROBLEM IDENTIFICATION


PRELIMINARY PROGRAM OBJECTIVES
a. Increased Agricultural Production
b. Increased Equity of Income Distribution
c. Resource Conservation


DEVELOP GENERAL OVERVIEW OF SYSTEM
w

Cn CONDUCT RECONNAISSANCE FIELD INVESTIGATIONS
m a. Plant Environment
z b. Form Management Practices
c. Water Supply and Removal a d. Institutinal Linkages


PRELIMINARY LISTING OF PROBLEMS


REFINE PROGRAM OBJECTIVES



DESIGN DIAGNOSTIC STUDIES



CONDUCT DIAGNOSTIC FIELD STUDIES
a. Plant Environment C b. Farm Management Practices
Cl)
0 c. Water Supply and Removal
d. Institutional Linkages


I ANALYSES AND INTERPRETATION OF FINDINGS


Of- IDENTIFY CRITERIA FOR SELECTION AND RANKING
OF PROBLEMS ACCORDING TO PROGRAM OBJECTIVES


REPORT FINDINGS OF PRIORITY PROBLEMS AND THEIR APPARENT CAUSES

Figure 3. Flow diagram of sequential activities in tIhe
Problem Identification phase.





22


3. To provide an understanding and overview of the system and
its problems to provide input for the design of more detailed
diagnostic studies.

These preliminary objectives are such that they provide definite focus to the researchers involved. The focus is on the farm,
constraints to agricultural production, and developing a preliminary list of problems that may need to be considered for the diagnostic field studies.


Reconnaissance Overview of the System

The reconnaissance phase or overview of the farm system is a basic learning situation that provides an opportunity to increase the general understanding of the farm situation. This includes the acquisition of background information from previous research that should be summarized. An agronomist, for example, will need information on climate, soils, current soil-water-crop management practices, and levels of current yields. Visits should be arranged with selected officials of organizations related to agriculture, such as governmental departments and universities; and selected personnel at research institutes. Staff must remember in such visits, however, that there is usually an "official view" that may or may not completely represent the realistic view. Project members involved in the reconnaissance should remain objective and reserve their views until empirical field data documents the real problems.
Reconnaissance activities also include informal interviews with selected farmers. These interviews should seek information about the farmer's views concerning crop production levels and constraints, management practices, economic conditions, and sociological aspects of the operation. Experience in Pakistan and Egypt has shown the number of researchers approaching the farmer should be relatively small to avoid intimidating the farmer. Questions should be carefully prepared in advance to obtain useful information. Also, those who interview farmers should be prepared and skilled in interview techniques. Information obtained from the farmer should be compared to that provided by officials and research stations by staff who should conduct meetings at the end of each day's activities.






23


Reconnaissance also includes preliminary field surveys, which should not be confused with the more detailed diagnostic surveys conducted later. The preliminary field survey is designed to provide an understanding and overview of the farm system and general areas where more intensive focus may be needed in the detailed survey.
At this stage selected field investigations will focus on the plant environment, farm management practices, water supply and removal, and institutional linkages. For example, the agronomist will want to gain an understanding of the general soil and water conditions, the growth status of various crops, and current cropping practices. Likewise, the agricultural engineer may want to learn about current irrigation practices, flow rates, drainage problems, and other factors. Prior to visiting the field the staff should have compiled sufficient background information combined with their own expertise and experience to develop a list of things to observe or questions to ask. For example, the agronomist may want to observe plant growth characteristics and experience in that area will help determine if growth is normal or abnormal. The agronomist may want to observe "above
ground characteristics" such as the status of plant nutrition, water relationships, pest infestation, or weeds. The agronomist may also want to make observations of root systems, crop stands, physical soil characteristics, and current crop management practices.
Individuals on the staff will collect preliminary data for planning the detailed field studies. However, it is possible to collect too much data or information at this stage. Information should be obtained from farmers about their fields, selected individuals who work directly with farmers, and officials. Information about the farm situation should be used to prepare a more detailed or diagnostic field study.


Preliminary Listing of Problems

The general information obtained from the initial field reconnaissance should be discussed in detail by team members who will propose a preliminary list of problem areas that may require intensive investigation. This can be done by referring to the preliminary objectives that provide criteria for selection of major problem areas. These criteria may include factors that limit crop production and the






24

productive capacity of small farmers, factors that inhibit the improved well-being of farmers, the conservation of soil and water resources, or other criteria established by the government, a funding agency, or staff members. It is important to be clear about the criteria because there must be priority in the areas that can be examined within limited resources of time, personnel, and funds.
A careful listing of priority problems that emerged from the problems identified on the farm system is much better than designing the diagnostic studies from unfounded ideas and assumptions that reflect only the interests or biases of researchers or officials of a funding agency.


Refining Objectives

The research team and officials of relevant agencies should then refine the preliminary objectives with respect to the knowledge gained from the reconnaissance field investigations. These objectives should be more clearly stated and specific than the preliminary objectives. For example, these objectives may include some of the following:

1. To make diagnostic studies of conveyance and field water
application losses.

2. To determine the constraints of waterlogging and salinity on
crop production.

3. To determine the constraints farmers face with regard to
supplies of essential inputs.

4. To determine the constraints of present water codes and
regulations on farmers' irrigation practices and maintenance of
the farm irrigation system.

5. To determine the fertility problems in relationship to crop
production levels.

6. To rank the major constraints to improved crop production for
all classes of farmers for the Development of Solutions phase. This brief listing is indicative of only some possible objectives for the more intensive diagnostic field studies.





25


Designing Diagnostic Studies

The next step is to design the diagnostic field studies. It cannot be stressed too strongly that this activity requires close collaboration with all concerned along with sufficient time to do a good job. Time utilized effectively in design of the field studies will be saved in producing good results.
A checklist is provided in Table 4 which shows some of the detailed activities involved in both the reconnaissance and the problem diagnosis subphases of problem identification (Figure 3). This list does not include every activity involved; however, it provides a method for the planning process. Those activities marked by an asterick (*) usually require team decisions and actions.


Conducting Diagnostic Field Studies

The detailed field studies are implemented to confirm constraints in crop production, some of which may have been tentatively identified in the informal reconnaissance field investigations. For example, more detailed measurements may be needed to ascertain yield and quality of crops.
Collaboration among the staff is required throughout the field studies. Just as there has been careful cooperation in the reconnaissance studies and the design of the more detailed diagnostic studies, there must be continued teamwork in the collection of field data. There is a tendency for researchers to work individually and become involved only with their particular activities. While various individuals will have specific tasks to perform, many of the field activities overlap and are the mutual responsibilities of two or more staff members. Close
cooperation is also needed because the data and the work output of one discipline is required by another. For example, maps will be used by all for the collection and recording of data. If the engineers develop or obtain a base map of farm irrigation sites to be studied, this map can be copied and made available for crop surveys, soil surveys, topographical surveys, cross sections, slope and length of the conveyance system, location of outlet structures, field ditches, drainage channels, recording groundwater fluctuations, farm size distribution, irrigation basin size, farm ownership patterns, tenure patterns, lan'





26



Table 4. Activities checklist for designing problem identification (P. I.) studies.



Sequence Activities

Preparation for P. I.
studies *Selection of investigators
*Selection of a team leader
*Team building training Discipline training in field methodologies
*Setting of priority objectives for reconnaissance

Obtaining a general
overview of system Identification and review of
available research
*Discussions with selected official/organizations
*Obtaining maps and other relevant resources
*Develop initial checklists of information needed
*Maintain current list of people to contact
Organization of
initial field visits *List objectives of visits
*Establish criteria for field sites to visit
*Determine responsibilities of each team member
*Review checklists
*Examine logistics

Implementing initial
field visits *Visit farms
*Encourage observational methods for all team members
*Conduct nonstructured interviews Selection of measurements
*Team collaboration on findings for each day
*Establish criteria for PI site selection

Prepare preliminary
list of problems *Team collaboration
*Devise criteria for selection of problems
*List problems
*Consult with all parties concerned





27


Table 4. (continued).


Sequence Activities

Design of diagnostic
field studies *Decide on site selection
*Develop PI objectives Design and test survey instruments
*Determine methodologies
*Select criteria for field workers
*Establish responsibilities for field workers
*Design and implement field :workers' orientation
*Design evaluative methods for field workers
*Design checklist of equipment needs
*Determine logistics
*Set-time frame
*Determine data management plans

*Denotes collaborative decision making.





28

fragmentation, and other important data. In other words, cooperation is not only essential, it is also a condition for successful interdisciplinary research in problem identification.
An example of the method by which group members might identify the data collected by one discipline which would be used by another cooperating discipline is shown in Table 5. It is obvious from the list that while all the data collected are used by the staff as a whole, certain types of data provided by disciplines with certain expertise are provided to other team members. This type of cooperation should occur throughout data collection activities to provide quality data without duplication and overlap.


Data Analysis and Interpretation

After the data are collected, data analysis and interpretation must be completed as a cooperative activity. Data analysis must be carefully planned at the time of design of the field studies if it is to provide useful findings. Most often data management including analysis is not planned adequately until after data are collected when it may be too late. Individual researchers may know how they will analyze their data; however, they seldom know how the data of several disciplines will be analyzed.
For example, a researcher would want to know what major factors influence the yields of specific crops in an area. Data may be available from field studies on fertilizer use, seed rates, water applications, sowing dates, and farmer extension contacts from several of the participating disciplines. In order to run a multiple regression or a stepwise regression, these data have to be from the same farms and of a quality that can be correlated. The point is that it is never sufficient to simply have data on the above factors by the various disciplines. Unless data are in a form so correlations can be made with the dependent variables, many types of analyses cannot be completed. Data must be analyzed and interpreted objectively and correctly to be useful.
In brief, data analysis should be designed so the results will indicate the priority farm problems limiting production. To provide a long list of problems without showing their relative relationship to each other is not sufficient. Problems or constraints to crop production





29


Table 5. Outline of selected types of data collected by one discipline
and utilized by another discipline.


Primarily
Collected By Used By Types of Data


Sociologists Sociologists Farmers perceptions about night
Engineers and day irrigation, major water
problems inhibiting increased yields, solutions to major water problems
Sociologists Engineers Farmer decision-making processes
Economists Agronomists related to crop decision-making,
Sociologists when to irrigate a given crop, when Economists to stop irrigation, water lift
methods, who applies water at given irrigation
Sociologists Engineers Farmers estimations of depth of
Agronomists infiltration of water, depth of crop Sociologists root system penetration, crop water requirements, critical water demand periods and stages of growth, sources of major losses, magnitudes of losses, waterlogging

Sociologists Engineers Propensity of farmers to cooperate
Agronomists in water lifting, trading of irriEconomists gation turns, farm implements
Sociologists and machinery sharing, sharing of work, patterns of both formal and nonformal cooperation

Agronomists Economists Farm management practices: cropping
Engineers patterns and intensities; seedbed
Agronomists preparation; levels of farm technologies; seed rates, quality, and seeding methods; fertilizer inputs, timing, amount and placement methods; harvest methods; storage methods

Sociologists Agronomists Adoption- diffusion of improved
Economists Sociologists technologies: rate of adoption, time
Economists required for adoption, disadoption,
channels and courses of information used at each stage in the process, characteristics of the innovation, farmer credability with information source





30


Table 5. (continued).

Primarily
Collected By Used By Types of Data


Economists Engineers Economic returns and costs: lifting
Economists water (alternative methods), various
crop mixes, storage systems, transportation, marketing

Sociologists Economists Legal and organizational factors:
Economists Agronomists delivery of water to command area,
Sociologists distribution of water, pricing of water, settlement of disputes formally and informally, farmer interaction with river irrigation officials, dejure compared to defacto, sanctions, incentives Engineers Agronomists Water supply and removal:
Engineers conveyance efficiency, field application efficiency, water quality, consumptive use, return flow, field topography

Economists Engineers Information for farm decision-making:
Sociologists Economists marketing, irrigation schedules,
Sociologists closures, extension, quality and quantity of information






31


must be ranked in relationship to specified criteria. Examples of
criteria that may guide the analyses may include constraints to crop production, constraints to small farmers' crop production, or levels of living of small farmers. Quantitative analysis alone will not necessarily provide the ranking of problems because sound judgments based upon experience also guide the data analyses and interpretation.


Criteria for Ranking Priority Problems

The ranking of priority problems requires that specific criteria be established. Decisions about criteria to be used may be political and reflect the philosophy or objectives of the government, or the government and a donor or funding organization. For example, it is assumed that the primary goals established by the government for improvement of farm irrigation systems are increased agricultural production, improved rural income distribution, and improved conservation of soil and water resources. These goals can be used as criteria for ranking the major problems that the Development of Solutions phase will investigate. An example of how problems might be ranked in terms of priority are shown in Table 6.


Table 6. Criteria for ranking priority problems.


Criteria Indicators and Dependent Methods of Ranking
Variables

Agricultural 1. Yields/ha and aggregate 1. Regression analysis, production yields analysis of variance,
team consensus

Income 2. Increased yields/ha and 2. Regression analysis,
distribution increased net income/ha cost-benefit farm
for small holders management analysis,
team consensus

Resource 3. Decreased water losses 3. Regression analysis,
conservation Decreased waterlogging cost-benefit analysis,
Decreased nitrate leaching team consensus More productive land
made available





32


If increased agricultural production is the primary objective, the major factors that significantly limit increased production will become central to the Development of Solutions phase. If income distribution is also a top priority by the government, the major factors that limit small farmers' productivity will also be included. Often these factors may be somewhat different from those that limit production on larger farms.
Finally, the judgments of the staff are also important and should be used in ranking priority problems along with statistical analyses. It is important to build a strong objective case for priority problems to present to officials who otherwise might attempt to influence the findings. Without good relationships and professional reporting in language that can be understood, individuals who are often not sensitive with local farm problems may attempt to force their conventional wisdom on the process.


Reporting the Findings

Findings of the diagnostic field studies should be prepared for two major audiences. Specially designed summary reports without too much technical emphasis should be prepared for policy-makers who need to be informed of the field studies. Often some problems identified in the field for which only political decisions are needed for solutions will be considered seriously by these policy-makers who need the field data for decision-making. Also, policy-makers need empirical data for use with internal and external organizations for funding purposes. More technical reports are required for the Development of Solutions phase to provide background data and benchmark data for their applied, adaptive, and evaluative research efforts to ascertain feasible solutions.
The chapter that follows provides the user with both reconnaissance and detailed diagnostic procedures for investigations related to the plant environment. Chapters III through VI contain
procedures and checklists that should be considered for investigation. Much variation exists between countries and regions within countries as to available data that can be used for problem identification studies. Valid and reliable data existing for specific factors listed in Chapters III through VI should be utilized. Variation also exists among countries






33


as to time and manpower available for these studies; therefore, the manual provides procedures for both short- and long-term diagnosis on irrigated farming systems.
A transition to the actual methods for reconnaissance and detailed diagnostic studies are described in Chapters III through VI. Figure 1 provides an overview to the four subsystems to be covered. In
Chapter III the focus is on the plant environment, while Chapter IV is related to farm management practices. Chapter V covers water supply and removal, and Chapter IV discusses institutional linkages. The
reader should remember that these subsystems are closely interrelated; however, each subsystem is examined and are treated separately in order to more clearly present the material. Then, in Chapter VII, the relationships between these subsystems are discussed along with analyzing and interpreting the findings about each subsystem.





34


CHAPTER III


THE PLANT ENVIRONMENT


The potential crop yield is first a function of the genetic character of the particular type and variety. The maximum attainable yield is a function of several interdependent positive growth factors. These growth requirements include 1) plant population (stand), 2) heat requirement (solar radiation), 3) carbon dioxide and oxygen requirement, 4) nutrient requirement, and 5) water requirement (soil moisture supply). Soil serves as a physical support system, a nutrient supply source, and a moisture storage reservoir for the crop plant. Solar radiation along with carbon dioxide and water are basic ingredients for producing sugars by the photosynthetic process in the plant. Oxygen is necessary for root respiration. Crop plants have specific requirements for nutrients, water, carbon dioxide/oxygen, and heat. If one or more of the requirements is less than or more than optimal, then crop production falls below the maximum attainable level.
Since optimum levels of all growth factors for all crop plants are not available at any given time or place in the world, it becomes the task of the farmer to manipulate, adjust, and manage all the positive growth factors so acceptable high crop yields are obtained. In addition, the farmer must contend with several negative growth factors. Weeds compete with the crop for water, nutrients, and radiant energy. Insects, diseases, and animals decrease yields or destroy crops. Inclement weather such as frost, hail, and excessive wind cause crop yields to be less than maximum. The delicate balance of all these
factors results in the actual yield obtained by the farmer. Thus, major factors that need to be examined in order to identify crop production constraints are types of crops grown, soil, climate, irrigation water, plant protection, and cultural practices (Figure 4).


CROPS AND CROPPING PATTERNS

When the problem identification process is applied to crops and cropping patterns, crop inventory, crop stands, crop damage, potential versus actual yields, and crop quality/nutritional value should be









Canal


-Crop inventory -Soil nutrient supply
-Crop stands .-deficiency
-Crop quality -inbalance
-Crop damage -toxicities
-weeds -soil root zone
-disease -physical properties
-insect -chemical properties
-rodent -subsoil properties
-animal -topography
-herbicide
-Crop yields




_1b,


Irrigation water Drainage Channels
SourceClmt < ~QualityClmt
AvailIabil1i ty Solar radiation
Surface flow ir -te mpatWure ---------2
Groundwater Relative humidity
Evapotranspiration Wind speed
-potential Evaporation
-actual Rainfall -r
Irrigation timing Crop adaptation
Climatic hazards
-wind
-flood
-frost
-hail
-high rainfall intensity
Figure 4. Idealized sketch of the plant envircnenrt.





36

considered. A brief explanation of each of these items follows, and at the end of this section there is a checklist of activities or methods that can be considered when applying the problem identification process to the plant environment. The checklist is divided into activities that could be accomplished during the reconnaissance phase and activities that could be considered during a more detailed problem diagnosis.


Crop Inventory
One of the first steps in determining specific crop constraints is making an inventory of all crops grown in an irrigated area. More detailed inventories that include acreage and total production are usually restricted to major crops important to goals of the project. The general inventory should include all crops because each minor crop may not be of much importance; however, an aggregate of all minor crops may require considerable expenditure of land, water, labor, and other resources. The usual sequence in which crops are grown (cropping pattern) should be included as part of the inventory. The crop
inventory is essential to determine constraints from such considerations as agronomic, engineering, economic, legal, and social factors.


Crop Stands

The plant population must be near optimum in relation to growth requirements if satisfactory crop yields are obtained. Optimum plant population should be determined in the climate and culture where it is grown. Generally, crop stands should be comparatively thinner as row width increases and for long-season varieties.
The crop stand attained is primarily dependent upon seed quality, proper seedbed preparation, seeding rate, method of seeding, time of seeding, seed treatment for disease control, soil and seed temperature, and moisture availability. Poor quality seed may contain undesirable varietal mixtures, weed seed, plant diseases, and other crops. Poor quality seed may also have low germination, which in turn, may be related to overaged seed, harvesting before maturation, freezing before maturation, heat damage, and improper storage conditions.





37


Crop Damage

The positive growth factors may be optimized for a given crop, but low yields or even complete crop loss may occur from crop damage. Crop damage may result from weeds, diseases, insects, rodents or other animals, bad weather, and herbicides.


Potential and Actual Yields

Potential yield is defined as the amount obtained with the best adapted crop variety grown with optimum nutrient and irrigation water levels, and the best-known management practices with adequate plant protection, all within the particular climatic setting. Actual yield is the results obtained by the farmer under his particular set of conditions.


Crop Quality and Nutritional Value

Quality and nutritional value of crops should be as carefully evaluated as the total yields. Yields of poor quality may be of less value than lower yields of higher quality.


SOILS

In examining soils, several aspects should be considered including the nutrient supply; physical, chemical, and biological conditions of the root zone; subsoil properties; and topographical problems. A checklist of reconnaissance and detailed diagnostic methods provided at the end of this plant environment chapter will serve as a guide in problem identification of soils.


Soil Nutrient Supply

Essential nutrient elements for most crops are considered to be the following:
Macronutrients: Ca, Mg, K, N, S, and P
Micronutrients: Fe, Cl, Zn, B, Mo, and Cu
Micronutrient requirements of plants are trace amounts.






38


Visual Observations

If no existing data concerning crop nutrient deficiencies and
supply is available, visual observations should be done. Severe
nutrient deficiencies can usually be identified in the field by characteristic plant symptoms. However, symptoms cannot always be observed at all stages of crop growth. This is especially true in the seedling stage because a seed usually contains enough nutrients, except nitrogen, to sustain the plant through that period.
General descriptions of nutrient deficiency symptoms are listed according to the probability of occurrence in irrigated arid-land soils, first for macronutrients and then for micronutrients.

Nitrogen: (N) Nitrogen deficiency symptoms on nonleguminous crop plants produce a leaf of pale green to yellow color. Nitrogen deficiency symptoms tend to be prominent on older leaves with more severe chlorosis followed by necrosis (death) of cells. This results in a characteristic "firing" of the lower leaves.

Phosphorus: (P) Phosphorus deficiency symptoms on crop
plants are usually indicated by a general stunting of all crop parts. Leaf color is usually a dull greyish-green and frequently anthocyanin (red color) accumulates in the leaf tissue and dying leaves.

Potassium: (K) Potassium deficiency symptoms on crop
plants are usually indicated by necrotic areas starting at the tips of leaves and spreading along the marginal edge. When N and K are simultaneously deficient, plants are stunted and their leaves are small with a somewhat ash-grey color, dying prematurely first at the tips and then along the outer edges. The fruit or seed is small in quantity, size, and weight. Deficiency symptoms usually appear first on the lower leaves or plants, progressing toward the top as the severity increases.

Sulfur: (S) Sulfur deficiency symptoms on crop plants
are similar to those of N except the symptom is characterized by uniformly chlorotic plants-stunted, thin-stemmed, and spindly. Unlike N, S does not appear to be easily translocated from older to younger plant parts under stress caused by deficiency.









Calcium: (Ca) A deficiency of Ca results in the failure
of the terminal buds and the apical tip of roots of plants to develop. As a result. of these two things, plant growth ceases. In corn, and to some extent, cereal grains, Ca deficiency prevents emergence and unfolding of new leaves whose tips are covered with gelatinous material that causes leaves to adhere to each other. This results in the classic
"ladder-effect" in Ca-deficient corn plants.

Magnesium: (Mg) Magnesium deficiency symptoms often appear
first on the lower leaves because it is a mobile element and is readily trans-located from older to younger plant parts. In most crop species, the deficiency results in an interveinal chlorosis of thp leaf so that only the leaf veins remain green. In more advanced stages, the leaf tissue becomes uniformly pale yellow, and then brown and necrotic.
In some species, notably cotton, the lower leaves may develop a reddish-purple cast that gradually
turns brown and finally necrotic.

Iron: (Fe) A deficiency of Fe shows in the young leaves
of plants. Iron does not appear to be translocated from older tissue to the meristematic tip, and as a result, growth is diminished. The young leaves develop an interveinal chlorosis that rapidly progresses over the entire leaf. In some cases, the
leaves turn completely white.

Zinc: (Zn) Deficiencies of Zn have been observed in
corn; sorghum; deciduous citrus fruit, and nut trees; legumes; cotton; and several vegetable crops. Zinc deficiency first appears on the younger leaves starting with interveinal chlorosis followed by a great reduction in the rate of shoot growth. In many tree crops this produces a
symptom known as "rosetting."

Boron: (B) Boron is not readily translocated from older
parts to the meristematic region, and the first visual symptom is cessation of terminal bud growth, followed shortly thereafter by death of the young leaves. The youngest leaves become pale green,
losing more color at the base than at the tip.

Manganese: (Mn) Like Fe, Mn is a relatively immobile element
and deficiency symptoms show up first in the younger leaves. Deficiency of Mn results in interveinal chlorosis, both on broad-leaf plants and members of the grass family, but is less
conspicuous on the latter.





40

Molybdenum: (Mo) Deficiencies have been reported for many
crops, including clover, alfalfa, grasses, tomato, sweet potato, soybean, and other vegetables. Symptoms of Mo deficiency differ with various crops, but they are first observed as interveinal chlorosis. Legumes usually turn pale yellow and become stunted; symptoms characteristic of N deficiency. These symptoms are consistent because Mo is required by Rhizobia for N-fixation and by non-legumes for NO3 reduction.

Copper: (Cu) Crops responding to Cu fertilization include
red beets, carrots, clover, corn, oats, and fruit trees. Deficiency symptoms vary with different
crops. In corn, the youngest leaves become yellow and stunted and as the deficiency becomes more severe, the young leaves become pale and the older ones die. In advanced stages, dead tissue appears along the tips and the edges, of the leaves in a pattern similar to K- deficiency. Small grains deficient in Cu lose color in the younger leaves that eventually break and the tips die. Leaves of many vegetable crops lack turgor, develop a bluish-green coat, become chlorotic and curl, and flower production fails to occur.

Miscellaneous: Sodium, chloride, and silica have been shown to be
beneficial for some crops, but no definite deficiency symptoms occur. Cobalt is reported to be beneficial for legumes and some non-leguminous plants and is essential for ruminant animals. Vanadium has been reported as beneficial for green algae and N-fixing bacteria.

It is often difficult to distinguish among deficiency symptoms in the field if more than one element is inadequate. Confirmation of
deficiencies by visual observation is frequently difficult or impossible if the deficiency is marginal. Also, disease and insect damage frequently will resemble certain micronutrient deficiencies. Therefore, it is usually necessary to employ supplementary techniques to refine or verify visual observations.


Tissue Tests

Another method for identifying soil nutrient problems is to take tissue tests. Important corollary factors that must be considered in interpretation of tissue test results include the general appearance and vigor of plants, level of other nutrients in plant, evidence of disease





41

and insect damage, soil moisture content, soil conditions such as poor aeration or poor tilth, climatic conditions such as unseasonable cold or heat, and time of day.
To take tissue tests, plant sap is extracted with reagents or by pressure. Tests for N, P, K, Mg, and Mn are made with various reagents giving semi-quantitative values interpreted as high, medium, and low. The best part of the plant to use for testing is generally that showing the greatest range as the nutrient goes from adequate to deficient levels. The part of the plant to be used is specified in the instructions for each commercial test kit. The parts recommended are based on mobility principles as illustrated by the following examples. As the supply of N decreases, the upper part of the plant, where maximum utilization of plant nutrients is in progress, will first show a low test for NO The reverse is true for P and K. Young leaves should not be tested, but leaves from an area that is somewhere between young and old, based on, the area where deficiency first occurred, should be selected.
In general, the most critical stage of growth for tissue testing is at bloom time or from bloom to early fruiting. During this period maximum nutrient utilization occurs and low nutrient levels are more easily detected. In corn the leaf opposite and just below the uppermost ear at silking stage is usually sampled. Thus, reconnaissance surveys should closely coincide to the early reproductive stage if posssible. However, early diagnosis of deficiencies in the post-seeding stage enables the application of fertilizer that results in increased yield the same season the deficiency is detected. The time of day a sample is collected influences NO3 levels in plants since NO3 usually accumulates at night and is utilized during the day when carbohydrates are synthesized. This results in higher NO3 levels in the morning than in the afternoon if the supply is short. Therefore, tests should not be made either early in the morning or late in the afternoon. Plant analyses are based on the premise that the amount of an element in a plant is an indication that supply of that nutrient is directly related to the availability in the soil. However, a deficiency of one element will limit growth, and other elements may accumulate in the cell sap and show high levels regardless of the supply. The apparent high levels may





42

actually be inadequate if the most limited nutrient is raised to an adequate level. Periods of intense cold or heat, and conditions of poor aeration may significantly alter the uptake level of different nutrients.


Paint and Spray Tests
Especially useful for diagnosing and confirming micronutrient deficiencies are paint and spray tests. If a uniformly chlorotic plant is found, 3 to 5 percent solutions of Fe, Mn, Zn, Cu, and a combination of all can be applied to different leaves with a paint brush. Leaf color changes occurring within a few days indicates deficiencies and response. Solutions may be sprayed on whole plants in a field or an area if a field is chlorotic.


Imbalances and Toxicity
An excess of one element can produce an imbalance in other nutrients and reduce crop yields. For example, an excess of Mg can produce a calcium deficiency. Micronutrients, such as excessive B, Zn, Mo, and Cu, produce a toxicity. Toxicity and nutrient imbalances
produce somewhat different symptoms on different crops. Only the
most skilled diagnostician is able to identify these problems visually. Usually plant analyses under laboratory conditions are necessary for satisfactory resolution of these complex problems.


Chemical Soil Tests
Advantages of analyzing soil samples are that 1) precise quantitative measures of available nutrients from thoroughly researched extractants can be obtained, and 2) analytical results from representative samples taken before the crop is planted can be used as guidelines for obtaining optimal yields. In some cases, sampling during the cropping season at periods of peak nutrient demand may be advisable. Certain nutrients on some soils may become limited during peak demand periods, such as initiation and reproduction.


General Fertility Guidelines
General guidelines for interpreting available nutrient levels are shown in Table 7.





43

Table 7. General fertility guicines for some nurtrients.


Very low Low Marginal Adequate High
Organic
Matter 1%
P 0-7 ppm 7-15 ppm 15 ppm
K 0-60 ppm 60-120 ppm 121-180 ppm > 180 ppm
Fe 0-2.5 ppm 2.6-4.5 ppm 4.5 ppm
Zn 0-.25 ppm .26-.50 ppm .51-1.0 ppm 1 ppm Mn 0-1 ppm 1 ppm
Cu 0-.2 ppm 0.2 ppm


Plant Analyses

Plant analysis in the laboratory is more precise, and a greater variety of analytical techniques can be used resulting in more quantitative data than with tissue tests. These analyses can be used in
relation to more specialized problems such as determination of efficiency of N-fertilizer usage.


Physical and Chemical Properties of Soil Root Zone

Portable equipment may be taken to the farmers' fields to study root zone properties. Tools needed include shovels, soil sampling tubes, a pocket knife, a bottle of 6N HC1, and a portable soil pH-test kit. Pits should be dug in representative areas to expose the full root zone depth. Systematic notes should be recorded for major horizons or layers in relation to factors such as root proliferation, texture, structure, compaction, lime content, salinity, pH, gypsum, and aeration.
For a detailed analysis, penetrometer, infiltration, and four-probe measurements may be required. The penetrometer can be used to
measure resistance to penetration in compact zone and hard-pan layers. This will give a quantitative measure that can be related to observed root penetration. Infiltrometers can be used to measure the relative difference between water movement in different layers. This is usually done with a double-ring infiltrometer. A vertical four-probe device can be calibrated and used to obtain measurements of root zone soil salinity (e.g., 15 cm intervals to 120 cm depth).





44


Subsoil Properties

Subsoil properties can be identified from visual observation of pits or soil cores. Notes on water table level, textural changes, and lateral permeability should be taken. Permeability measurements are usually made by the auger-hole and piezometer methods. These measurements are used to assess drainage feasibility and to calculate drain spacing.


Topography

If topographic maps are not available, measurements of elevation and slope must be taken. Elevation affects the quality of the incident solar radiation absorbed by the crop. Thus, information concerning the general elevation of an irrigated area and its variations should be obtained. Depressions and low-lying areas that may be more susceptible to frost or cold air drainage should also be considered. Low-lying terraces along rivers that may be more subject to flooding and a fluctuating high water table should also be noted. Amount of sloping land in the area should be obtained, as well as measurements of the degree of sloping. Evidence of erosion indicating an improperly designed irrigation system should be acknowledged. Very flat land with little or no slope may represent drainage problems. Special precaution must be made to note a "closed-basin area" in which no surface or subsurface drainage occurs away from the irrigated area.


CLIMATE

Climate of an irrigated area generally controls the crop production attained since it cannot be changed much by man. Climatic data,
therefore, are necessary to determine and evaluate many crop production restraints including water supply, crops produced, crop water requirements, incidence of insect pests and diseases, and availability of soil nutrients.


CHECKLISTS

An example checklist is shown in Table 8 for reconnaissance of crops and soils. For the Problem Diagnosis subphase, Table 9 provides a checklist for studies of crops and soils.





45


Table 8. Checklists on reconnaissance methods for crops and cropping
patterns and soils.


*NOTE TO USER: These checklists are to be used as a guide and are
not complete for every situation. Areas of investigation may have to be added to meet project requirements. Particularly in the reconnaissance phase, utilization of existing data will save much time. However, observations on the farms and personal contact with farmers to verify the data must be made by project personnel.


CROPS AND CROPPING PATTERNS

Crop inventory: Obtain existing information, including general
maps, from official agricultural statistical agencies.
Obtain existing information, including possible detailed field maps, from irrigation officials. Obtain aerial photos used in soil surveys showing field layout farms. Gather information by interviewing selected farmers.
Observe crops grown on-farm. Other (specify)

Crop stands: Field observation: well-trained agronomist
can estimate plant population with considerable accuracy.
Calculate plant population from seeding rate and purity under various conditions. Other (specify)

Crop damage: Obtain existing information from such sources
as plant protection officers or experiment station personnel.
Make field observations at various times during the cropping season to identify types of damage occurring.
Interview farmers for general information on damage factors.
Other (specify)

Potential yields: Obtain data on potential yields from local
experiment station. (Exercise judgment in determining how closely optimum conditions have been met).
Interview local "best farmers" for insight into potential yields in the area. Other (specify)





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Actual yields: Obtain field observations of harvest.
Interview local farmers.
Obtain agricultural statistics from government agencies.
Other (specify)

Crop quality/
nutritional value: Observe and evaluate qualitatively crops by
trained agronomists and nutrition specialists. Place qualitative value on total calorie content from generalized knowledge of average carbohydrate, protein, and fat content. Other (specify)


SOILS


Soil nutrient
supply: Obtain existing data from agricultural
agencies.
Use visual observation of plants. Take soil and tissue tests. Conduct paint and spray tests. Other (specify)

Root zone physical &
chemical properties:
Check root proliferation: depth and pattern of root development. Should record changes in rooting habit with textural changes or other layer changes. Shallow restricted root zone is evidence of a root-zone problem. Determine soil texture. Moisture retention is mainly related to texture. Note soil structure type and degree of development. Also, record evidence of aggregate breakdown, surface crusting, and cracking.
Study compaction. Evidence of compaction or tplow sole" can usually be seen and confirmed by resistance when pushing a soil sampling tube into the soil.
Record lime content as low, moderate, or high as judged from effervescence of CO2 when HCl is dropped onto soil. Physically hardened layers should be noted.
Obtain evidence of salt accumulation if present at either the surface or in root zone. Detrimental accumulations of salt can usually be tasted with the tip of the tongue, whereas lime and gypsum cannot.






47


Field-test pH. A field-test of pH of 9 or more indicates either excessive Na or excessive Mg. A lower pH, however, does not eliminate either Na or Mg as a problem. Examine gypsum layers within the root zone. Thick gypsum layers may impede root development because of infertility or physical hardening, impede water movement, and may lead to subsidence of land under irrigation. Check aeration. Waterlogging and reducing conditions result in a mottled soil color. Other (specify)

Subsoil properties: Check water table level. Shallow water table
results in poor root aeration and acceleration of salt accumulation in the root zone. Note abrupt changes in soil texture from silt or clay to sand or gravel. These changes
impede water penetration and can cause a "perched water table."
Other (specify)

Topography: Measure elevation of fields.
Check amount of sloping land in area. Measure degree of sloping in the area. Other (specify)





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Table 9. Checklists on detailed diagnostic methods for crops and cropping patterns and soils.


CROPS AND CROPPING PATTERNS

Crop inventory: Take aerial photographs to determine field patterns and sizes.
Calculate acreages involved from average field patterns and sizes.
Interview more farmers and at greater length than before.
Other (specify)

Crop stands: Obtain field measurements. Stand counts in a
measured area at several places in the field may be used to calculate a mean plant population for the entire field. Calculate germination percentage. Germination percentages should be determined from seed sold by dealers and seed held over from previous seasons by farmers. Take impurities tests. Determine amount and kind of weed, other crop seed, and varietal mixing in representative crop seed from the irrigated area under investigation. Investigate low germination seed. Signs of excessive heat, excessive cracking, shattering from freezing, interrupted germination, or excessive shrinking from respiration during storage will help determine the causes of low germination.
Examine seedbed. Look for evidence of soil crusting; excessively shallow or deep seeding; or lack of moisture or excessive moisture. These parameters may explain poor stands when seed has a high germination rate. Study time of seeding. Check time when the seed was planted. Seeding when the soil
temperature is too hot or cold may cause low germination and poor stands. Investigate seed and seedling disease. Field examination at emergence or post-emergence may be necessary to detect stand loss from seedling diseases.
Other (specify)
Crop damage: Take complete inventory of weeds, diseases,
insects, rodents and animals, weather conditions, and herbicides in location under examination.
Other (specify)





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Potential yield: Cooperate with local farmer to observe fields
under carefully defined and controlled conditions to determine the potential yields of various crops.

Actual yield: Use spot field measurements in small sample
areas of local farmers' fields. Interview farmers to determine amount of crop sold, consumed by the family, and needed for barter payments.

Crop quality/
nutritional value: Take chemical analyses to determine specific
kinds and contents of sugar and starch in carbohydrates, amino acids in protein, and kinds of lipids in fat. Analyze vitamin and mineral content. Evaluate changes brought about by processing and cooking.
Other (specify)


SOILS


Soil nutrient
supply: Analyze soils for organic matter and nitrate,
lime content and pH, phosphorus, potassium, sulfate, boron, iron, zinc, manganese, and copper.
Do plant analyses. Use field fertilizer trials. Other (specify)

Root zone physical &
chemical properties:
Take soil samples. Characterize by saturated paste extract, ammonium acetate extract, pH, cation exchange capacity, calculation of SAR, lime content, and gypsum content. Take penetrometer measurements. Make infiltration measurements. Measure soil salinity with four-probe device. Other (specify)

Subsoil properties: Check lateral permeability in the fields.
Other (specify)





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INTERDEPENDENCY OF PLANT ENVIRONMENT WITH FARM MANAGEMENT PRACTICES

Providing optimal growth conditions for crop plants in order to attain high levels of production are complex and sensitive processes that are usually intricately related with management. In the Problem Identification phase, identifying a deficiency of a particular growth factor is usually only the initial step in identifying the exact cause or causes of the problem. A particular growth factor deficiency or
inefficient utilization of the growth factor by plants can generally be traced to management-related causes. The cause of the problem may not be readily apparent, but in most cases the cause can be revealed by studies of farm management and farm services in an irrigated area. Most farmers can seldom, if ever, be accused of deliberate mismanagement. Poor management is created most often by lack of knowledge or specific information and unfavorable economic factors, sometimes by social constraints, and quite often by factors beyond the control of the farmer. Therefore, careful studies of the farm setting and management practices are mandatory for identifying problem causes. Guidelines for such studies are explained in Chapter III, "Farm Management Practices."
The following hypothetical example illustrates how a general fertility problem, such as N-deficiency, might be traced to managementrelated causes. The general problem is presented and different specific causes are listed in Table 10.


Case Study

Observations of plant growth by technicians in the field during a reconnaissance survey of farms indicated a nitrogen (N) deficiency for a given summer crop. This was confirmed by plant tissue tests. More detailed studies of plant samples also showed the N-fertilizer that was applied by the farmer was not used efficiently by the plant which had a low N-recovery. Interviews of farmers within the area revealed that N-fertilizer was not available on the local market at the time fertilizer was normally applied due to a strike by transportation workers. After some delay, the farmers planted the crop without the usual broadcasting (throwing material by hand onto the ground surface) of fertilizer and






51



Table 10. Hypothetical case study of symptoms and causes of
nitrogen deficiency.



Fertility Problem

1. Nitrogen (N) deficiency
2. Low. N-recovery by plant

Visual Symptoms

1. Pale leaf color
2. Firing of lower plant leaves

Measurements of N-deficiency and N-recovery

1. Plant tissue tests
2. Plant sample analysis

Possible Cause or Causes of N-deficiency

1. Low inherent N-fertility
a. Low soil organic matter content
b. Low rate of organic-N mineralization
c. Failure to incorporate crop residues in soil
d. Continuous deposition of silt from irrigation water

2. Low N-recovery
a. Ammonia volatilization of broadcast ammonium-N or urea-N,
fertilizer not mixed into soil quickly
b. Leaching of nitrate-N below root zone by excessive irrigation
conditions
c. Nitrate reduction and gaseous-N escape under reducing
conditions
d. Ammonium-N fixation by mica and vermiculite clays
e. Deficiency of other nutrients such as P

3. Application of N less than that required to produce a given
crop yield
a. Fertilizer too costly
b. Fertilizer not available on open market
c. Fertilizer not distributed uniformly over field
d. Inaccurate fertilizer recommendation

4. Fertilizer not applied at recommended time
a. Lack of information about timing
b. Fertilizer not available when needed
c. Insufficient labor or machinery at critical time
d. Inaccurate fertilizer recommendation





52

working it into the soil before planting. The strike was settled and farmers bought fertilizer after the crop had emerged and broadcast the fertilizer on the soil surface but could not incorporate it into the soil. The fertilizer (urea) sat in the hot sun on the ground surface several days before irrigation water was first applied. Farmers observed that the crop did not grow normally and since an above-normal supply of water was available at that particular time, extra heavy irrigations were applied with the hope that extra water would improve crop growth. Crop yields for this particular season were substantially lower than the previous average.
In this case study, no one particular cause can be cited for the N-deficiency. It is highly probable that volatilization losses of ammonia from the urea were high because the urea sat in the hot sun for several days. It is also probable that further losses of N below the crop root zone resulted from overirrigation. Some loss in yield probably resulted from the delay in planting the crop as well. Thus, part of the management problem was due to circumstances beyond the control of the farmer. The failure of the farmers' attempt to compensate by overirrigating was due to lack of knowledge concerning the leaching process.





53


CHAPTER IV


FARM MANAGEMENT PRACTICES


Good farm management practices are essential to increased agricultural production. In order to identify problems that impede optimum production, the Problem Identification phase must include a close examination of the farm management practices in the irrigated area under study. As with each phase of this process, examining the problems with farmers is important to success. This chapter will focus on inventories of management practices, cropping patterns, and resources; farm budgets; the farmers' decision-making environment; and the interdependency of the management practices with the farmers' community (Figure 5).
There is a natural overlap between many aspects of the plant environment and farm management practices. This is true for the agronomist and agricultural engineer who are concerned with soil and water management practices employed by farmers on cultivated fields. Much of this information is used by the social scientists. The farm management economist is concerned with cooperative costs and benefits of alternative management practices. Both the economist and sociologist or anthropologist is interested in the decision-making environment and its impact on farm management practices.


IRRIGATION PRACTICES

The specific methods of irrigation for various types of crops need to be identified and evaluated for effectiveness. Field application
evaluations will help determine whether the farmer is overirrigating or underirrigating in relationship to crop demands and water required to maintain adequate control over salinity problems. These evaluations should supply data on the desired volume of water distributed uniformly over fields, erosion and salinity control, drainage problems, and the economic feasibility of the methods used. Important variables in these irrigation evaluations include water supply rate, field geometry (length and width), slope, infiltration rates, surface roughness, channel slope,











Canal-- -Inetr of Practices Inventory of Resources
-Field descriptions (Composite 'Farm Budgets)
-Seedbase preparation -Land
-Cropping patterns -Labor
-Purchased inputs ,-Physical capital
-fertilizer -Commercial inputs
-seed -Water inputs
-pesticides -Output
-herbicides -machinery
-Irrigation
-Harvest
-Storage CDecision making
Environent
PricesT
-Tenurt
-Farm practices Non

'Drainag sk els
Cropping Patterns Cropping intensities Crop rotation Crop mix x Polyculture




Figure 5. Idealized sketch of a farm irrigation system and farm management practices.





55

and management decisions related to the methods. Three basic questions that need answering are: How does the farmer irrigate?
When does the farmer irrigate? How much water does the farmer apply to various crops? The major task is to evaluate irrigation practices in relationship to costs of alternative methods.


Farm Water Use Efficiency

Farm investigations constitute the largest proportion of work involved in the evaluation of an irrigated area. The primary component of this investigation is the farm efficiency studies which include evapotranspiration, infiltration, tailwater, irrigation method analysis, and vegetative land use mapping.
The amount of water diverted is also very critical in establishing the water-salt budgets for a farm or a field. All of this water must be measured and accounted for, and it is allocated to any one of three main catagories. The surface hydrology categories are
(a) evapotranspiration, (b) infiltration and (c) tailwater runoff (Figure 6). In areas with a high water table, there can be a substantial amount of water that moves upward via capillary action from the water table and is used by the plants. This capillary water will usually contribute significantly to soil salination problems. The subsurface hydrology categories are head ditch seepage and deep percolation losses. The variables that must be considered in an
on-farm irrigation investigation are schematically illustrated in Figure 7.
Many of the parameters such as drainage discharges, watercourse diversions, water quality, and precipitation can be measured directly. Others must be investigated indirectly. These indirect measurements of parameters are related mostly to groundwater movement and soil hydraulic characteristics and can be monitored using techniques such as piezometers, wells, and soil sample analyses.
Because so many of the parameters in the water and salt budgets cannot be evaluated directly on a large scale, peripheral investigations are usually made in which a portion of the area is examined in detail. Such investigations include farm efficiency studies that indicate the relative proportion of evapotranspiration, deep percolation, and soil moisture storage; vegetative land use mapping of the entire irrigated


















River





Flow Measurement
Structures
felSoil Moisturne



Hydraulic Elevation ofC)
Irrigation Performanco FlOW Measur cni
Weather a < Structure
Station -un t

Tailwater
Deep Percolation Runoff
Losses

Note: Schematic illustrates furrow irrigation. Border irrigation would be similar.
Basin irrigation would not have tailwater runoff.



Figure 6. Schematic of instrumentation required for on-farm hydrology investigations.






57












Transpiration






















N

00

O



0
Root Zone
Extraction

Deep
Percolation
Upward Flow by Capillarity
0
Water Table Groundwater Flow ci) apillary Fringe
of Water Table



Figure 7. Schematic of the hydrologic variables to be considered in an on-farm subsystem investigation.





58


area so that the total consumption of water for the area can be calculated; and other studies pertaining to specific conditions of water and salt movement. There is no substitute for good field data
collection. The United States Geological Survey (1968 to 1976) has published 34 manuals on techniques used for water resource data collection, many of which are very useful for irrigation studies.
Four types of basic data are required for on-farm water use investigations. These are crop parameters, soil parameters, water quality information, and climatic data such as evapotranspiration and precipitation data.
Crop parameters are important to many of the irrigation method decisions and the plant sensitivity and ionic toxicity response to salinity, growth rates, and evapotranspiration demands. Crop responses to salinity are discussed by Bernstein and Hayward (1957), Bernstein et al. (1954), Black (1968), Maas and Hoffman (1977),
Robinson (1971), and others.
Soil parameters considered as basic data include field capacity, permanent wilting point, and bulk density for each soil layer with depth. Since field soil-moisture sampling procedures are gravimetric, the bulk density is needed to relate gravimetric to volumetric moisture content which is used in most analytical procedures. An attempt should be made to obtain several samples from numerous locations to approximate the average conditions of the field (Warrick, 1977; Karmeli et al., 1978). Basic soil chemistry reactions, electrical conductivity and ionic content of the soil solution should also be determined. Black et al. (1965), Food and Agricultural Organization of the United Nations (1975), Quirk (1971), Richards (1954), Chapman (1966), and others describe the soil-chemistry-plant relationships and procedures for data collection and analysis.
Quality of the incoming water can greatly influence management and operation of an irrigation system. If the water is of poor quality, it can limit many of the alternatives for pollution control. Ayers
(1976), Ayers and Westcot (1976), Christiansen et al. (1976), Kemp (1971), Kovda et al. (1973), Wilcox and Durum (1967), and others present information regarding water quality in irrigated agriculture.





59


Crop Water Use
Evapotranspiration (ET) or consumptive use (CU) is the sum of the amount of water evaporated from the soil surface and the amount of water transpired by the crop. The primary factor controlling ET is the thermal energy of solar radiation reaching the surface of the earth. However, solar radiation, air and soil temperature, humidity, vapor pressure, wind velocity, and specific crop and variety are all interrelated factors in the ET process. Potential evapotranspiration (ETp) is a convenient weather index or reference point by which weatherrelated evaporative conditions can be related to specific crop-water needs. Potential ET has been measured as open-pan evaporation and calculated by various formulas that include varying amounts of climatological data with and without corrections for altitude and latitude. The Jensen-Haise method uses calculated ETp from solar radiation for alfalfa as a reference crop. Actual evapotranspiration (ETa) is usually less than potential evapotranspiration because of moisture stress experienced by the plant prior to irrigation, unless sufficient irrigation water is applied frequently.
Some data on ET may already exist at universities, experiment stations, or governmental agencies. Data for crops in other irrigated areas with similar climatic conditions transferred directly to local settings may be accurate enough for some purposes. In the absence of ET data, calculations can be made from existing weather data for the local irrigated area using crop coefficients developed in other areas.
Determination of ETa at the peak, with maximum rates occurring near the onset of flowering and minimum rates occurring near the germination and late maturation stages, is necessary to determine the proper time for irrigation. Probably the most accurate way to measure ETa is from lysimeters; however, gravimetric moisture or neutron probe measurements taken before and after irrigation under field conditions where no water table exists near the crop root zone can be satisfactory. Weighing lysimeters surrounded by the same crop can furnish daily ETa data more easily than soil moisture sampling. Considerable care must be taken to duplicate conditions of the natural environment or else results will not duplicate those found in the field.






60


Inflow-outflow studies along with accurate water table level measurements can furnish sufficiently accurate average data for large areas. Crop water-use coefficients (k or K) can be developed from ETa data at the various stages of crop growth for particular ETp data.


Open-Pan Evaporation

Open-pan evaporation data can be used as a direct measure or index of ETp. Daily data can be summarized for various growth
periods by months or for different seasons.


Other Devices for Measurement of Evaporation

Piche tubes and atmometers have been used in many places but have not achieved popularity in the United States. Use of these
devices would necessitate the development and use of some different crop coefficients than for open-pan evaporation.


Calculation from Weather Observation Data

Potential evaporation has been calculated or estimated by many different formulas varying in complexity. The following formulas are listed in a decreasing order of the amount of weather data needed: Penman, Christiansen, Hargreaves, Jensen-Haise, Blaney-Criddle, Thornewaite, and Lowry-Johnson. The Penman and Thornewaite
formulas are best adapted to humid, well-vegetated areas.
Tanner (1967) and the World Meteorological Organization (1966) provide an excellent review of the procedures and methodologies used for the measurement of potential evapotranspiration in, the field. Measurement of evapotranspiration should include the means for the actual measurement of consumptive use and a complete weather station to measure air temperature (including maximum and minimum daily temperatures), dew point temperature, relative humidity, precipitation, wind run, solar and net radiation, and evaporation (Class A pan). Doorenbos (1976) presents an excellent discussion on the establishment and operation of a weather station and the calibration of empirical evapotranspiration indices to actual evapotranspiration measurements. The World Meteorological Organization (1970 and 1971) presented much information on the collection and analyses of hydrometeorological data.





61

Lysimeters

Probably the most accurate measurement of evapotranspiration is obtained by the use of lysimeters. A lysimeter is a device that is
hydrologically isolated from the surrounding soil. This device contains a known volume of soil, is usually planted to the crop under study, and has some means to directly measure the consumptive use of water. Lysimeters must be representative of the surrounding conditions and the soil types if they are to provide useful evapotranspiration measurements. Lysimetry establishes a datum for evapotranspiration calculations because it is the only method of measuring evapotranspiration where the investigator has complete knowledge of all the terms of the water balance equation. Harrold (1966) presents a comprehensive review of the use of lysimeters for measuring evapotranspiration.
Two types of lysimeters, which have worked quite well for calibration purposes, are the constant water table and the hydraulic weighing lysimeters. The constant water table lysimeters (Figure 8) are usually planted to grass or other crops with shallow root systems. On the other hand, the hydraulic weighing lysimeters (Figure 9) are usually planted to deeper rooted crops, such as alfalfa or corn.


Irrigation Timing
Irrigation water must be applied frequently enough so the crop is not subjected to a great degree of soil moisture stress in order to achieve full production. Proper timing depends on the water requirement of the particular crop, the stage of crop growth, the moisture storage capacity of the soil, and availability of water to the irrigator. Maintaining readily available soil water is essential if crops are to achieve satisfactory growth.


Field Observations

Determination of soil moisture content can be done by the Touch and Feel method. Soil that will not form a ball is an indication of
inadequate soil moisture. A dark green color and signs of wilting by the crop indicates that soil moisture is limited. However, these
symptoms may be difficult to distinguish from the symptoms of salinity.















Water Stage Recorder






Reservoir Float Valve

0~
Sod :
SS2 Tubing




XWelded Aluminum Lysimeter
Tank Imxlm x 0.46m


Figure 8. Schematic of constant water-table lysimeter.



















2cm I18 cm 2cm Flexible Plastic Manometers
Water Seal (filled with antifreeze)







122 cm Vle- Hg
1.2 cm Diameter V
I Bar Ceramic Candle

Pressure Line Constan
(6.5 mm Imperial Tubin cuum

Drainage Line TSample Dummy Lysimeter

Nylon(6.5mm Imperial Tubing) Collection Bottle for Temperature Correction
Butyl Rubber Tubing



Figure 9. Schematic of the construction of a hydraulic weighing lysimeter.






64


Calculations of ETp and E'Ta frcm l Data

Estimates of soil moisture-holding caPacity along with ETa estimates for a specific time period give a reasonably good indication of the rate of crop-water use. If available water stored in the root zone at each irrigation is less than estimated ETa for that period, calculations indicate that irrigation is applied too infrequently.


Field Measurements

Fundamental characterizations for evaluating proper irrigation timing is the determination of field capacity, wilting point, and amount of available soil water stored between these two values for a given soil. Usually the best crop growth will be obtained if soil moisture does not fall below 50 percent of the available supply, generally called the "readily available" supply. In terms of soil moisture stress, the readily available moisture usually falls into the range of less than 1-2 bars tension.


Tensiometers, Gypsum Blocks, or Fiberglass Blocks

Tensiometers are well-adapted for sandy soils. The range in their measurement is from 0-1 bar tension. The range in gypsum and
fiberglass blocks is from 1-15 bars tension and these are best adapted to medium-to-fine-textured soils. The above devices can be used as a check to see if irrigation frequency is satisfactory or as a guide to application time.


Gravimetric and Neutron Probe Moistlure Measurements

Either gravimetric soil moisture samples or neutron probe measurements can be used to evaluate the acceptability of the usual timing of irrigation. These measurements can also be used to develop guidelines for the best irrigation timing practices. Measurements of this type are usually fundamental for any "water budget" or "water balance" studies, which are defined in the next chapter. Direct
measurement of soil moisture is potentially the most accurate method for evaluating irrigation timing, especially if groundwater is utilized by plant roots.





65

Irrigation Timing as a Function of ET Estimates

Estimates of ET from open-pan measurements and/or climatic data entail somewhat less work than gravimetric moisture sampling or neutron probe measurements since they are independently determined. If it is possible to change the time of irrigation, then it can be adjusted to fit climatic changes.


CROPPING PRACTICES

Cropping Patterns

Cropping patterns, as shown in Figure 10, refer to the cropping intensities and crop rotations including fallow, crop mixes, polyculture, and relay cropping. The first step is to determine the definition of cropping intensity being used in the region or country. Usually there is one accepted definition used by the agricultural census or the Department of Agriculture in a country. Some definitions and examples of cropping intensities are given in Table 11.


Crop Rotation
Investigation of crop rotations ascertains the actual sequences of crops grown on different fields. Also, the use of fallow for each field over time is recorded.


Crop Mixes
The purpose of a crop mix study is to check the types of crops cultivated for individual farms and a large area. For example, is the farm primarily a wheat-cotton farm, a wheat-fodder farm, a vegetable farm, or one with a variety of crops?


Polyculture
Polyculture is the degree of intercropping of several crops in a single irrigation basin or field, and should be determined. In many parts of the world there are sound reasons for polyculture. Farmers with small acreages report that such practices exist for several reasons such as there is a more even distribution of income over the year, a lack of sufficient land to feed family and animals, insurance against one





66
WATER MANAGEMENT RESEARCH PROJECT WATERCOURSE SURVEY SAMPLE VILLAGE= NO. 103

DISTRICT LAHORE

WATERCOURSE COMMAND I



GENERAL FEATURES


N


r FW

BrF W, 1-4 Frr sF
rW FF





B FFF BEF

FF Br B-r
W W Sc r WW




SEW W
WWW













M~W rNKA UUL BARE
FFF



















HLGENDAEBONDR
W- TWE FigureE RS
F-FALLO
Sc-UGA CAN





GREND

WlHB- MINOR

B-WAERCOUE


Nr-AKKS:R NCLEBRE

* -DITALARYAROUDR



TUBEWELL/MOGHA .AREA BOUNDARY

Figure 10. Example of agricultural. land, use, mapping.





67



Table 11. Definitions of cropping intensity.


Definition 1: Total area in acres or hectares
cropped for two major seasons x 100
Total area of cultivated acreage
or hectares

Example: A farm has 5 acres and two seasons (two crops per year can be harvested). If the farmer
cultivates the five acres each season, then a total of 10 acres is cultivated each year and the cropping
intensity is

10/5 x 100 = 200%

Definition 2: Total area in acres or hectares
cropped for more than two major
crops x 100
Total area of cultivated acreage
or hectares

Example: If a farm having 5 acres can grow three crops in a year and 5 acres are cultivated one season, 3 acres another season, and 4 acres for another season then the
cropping intensity is

12/5 x 100 = 240%

Definition 3: Total area in crops harvested in
two or more seasons x 100
Total area cultivated

Example: A farm has 20 cultivated acres but 10 acres are in perennial sugar cane harvested once a year and 10 acres in other crops for 2 seasons per year, the
cropping intensity would be

30/20 x 100 = 150%*

The 10 acres of sugar cane are counted as 10 acres because they are harvested on a yearly basis (which would also be true for tree crops). The other 10 acres produces 2 crops per year, so it is counted as 20 acres in the numerator.






68

crop failing, an improved crop cover, better utilization of water and fertilizer inputs, symbiotic (nitrogen fixation) relationships of some crops, insect protection, along with other advantages. However, little experimental work has. been completed related to this widespread practice on many farms around the world.


FARM BUDGETS

Farm Management Inventory

It is necessary to collect data from farmers about their actual management practices (Table 12). Checklists are provided in Tables 13 and- 14 for evaluating farm management practices. Data obtained from a representative sample of farmers can help program staff answer many questions about farm management.


Resource Inventory

In addition to technical information about actual farm practices, it is necessary to gather information about resources available to the farmers and the values of these resources in production. Preparation of budgets require price information and; inventories. When price information is complete, detailed farm budgets can be constructed for use in analyzing the farmer's production choices and the value of his resources.
Farms should be separated into homogeneous groups with respect to their availability of resources and their productivity. For example, farm size, tenure, and location may be adequate indices by which to categorize farms. Thus, one category might be "small, low-land, tenant-operated farms." The area map mentioned earlier should be useful to determine the categories. Each category is then used to compute an average or representative farm budget. As part of the
detailed diagnosis, a sample of land, physical labor, capital, animals, water, and outputs should be made.


Land

Soil types and productivity, accessibility to markets for products and inputs, size and shape of fields size of holdings, access to water, ownership and tenure arrangements, and markets and prices should be





69



Table 12. Format for inventories of actual practices for major crops,



A checklist in a formulated systematic approach for obtaining
and preserving management data is as follows:


1. Name of farmer Date
2. Legal description of farm
3. Field designation
4. Field size
5. Preceding crop
6. Preceding fertilizer application a. Amount of N, P, K, micronutrients applied
b. Manure
7. Present crop
8. Seedbed preparation
a. Type or types of tillage operation
1. Number of times and sequence
2. Type of power (animal, machine, man)
3. Desired seedbed condition (firm, mellow)
4. Planting system and method of planting
b. Time and labor required
9. Number of irrigations applied during land preparation 10. Fertilizer applied
a. Amount (N, P, K, micronutrients)
b. Method of application (broadcast, banded, split)
c. Number, type, and time of tillage operation to incorporate
fertilizer into soil
d. Commercial fertilizer cost ll. Seed
a. Source
b. Seeding date or dates
c. Purity (weed and other crop free)
d. Opinion of quality
e. Amount of seed planted (calculate seeding rate)
f. Cost
g. Method of planting
h. Seeding depth
i. Condition of seedbed (firm, mellow, moist, dry)
j. Type of power (man, animal, machine)
k. Time and labor required for seeding
1. Cost of custom work 12. Weed eradication
a. Preplant spray; material
b. Mechanical cultivation; man, animal
1. Date, number of times
2. Time and labor required for weeding
3. Cost of custom work






70


Table 12. (continued)

13. Irrigation
a. Method of irrigation
b. Dates and number of times
c. Irrigation intervals
d. How much applied each time
1. Amount. of water received
2. Length of time on field
3. Amount of runoff (calculate field efficiency)
e. Labor required
14. Insect problem if noticed
a. Amount, type, and number of sprays
b. Cost of sprays
c. Time and labor involved 15. Disease problems if noticed 16. Other damage to crop
a. Farm animal, rodent or other, wind 17. Harvest operation
a. Date (period) of harvest
b. Method of harvest
1. Power source
c. Time and labor required 18. Yields
19. Storage facilities
a. Capacity
b. Amount stored 20. Cropping patterns
a. Cash crops
1. Number, sequence, and time and duration during
year
b. Subsistence crops
1. Number, sequence, and time and duration during
year
c. Crops grown together (crop mixes)
d. Intercropping practices (polyculture)





71

Table 13. Checklists on reconnaissance inventory for farm management practices.


Cropping patterns: Consult available data
Discuss with farmers and those who work directly with farmers
Make direct field observations where possible Other (specify)

Irrigation practices:
Consult available data from research stations, etc. as to comparative benefits of various practices used
Field visits to observe the alternative practices used
Discussions with farmers and extension personnel of comparative benefits of alternative methods
Other (specify)

Resource inventory/
farm budgets: Consult available data: census, agriculture
department, agricultural studies, anthropological studies, marketing board, ministry of trade, labor data
Check existing data for farm size, tenure system, water rights, capital availability, pricing policies, government policies Determine government policies on agriculture commodities, quotas, prices, and distribution of fertilizer
Check with agriculture extension agents for existing data and to see if government policies are effective
Other (specify)

Decision-making: Determine degree of fluctuation in prices of
commerical inputs and crops. Comy ute statistical variance, range, and use a scatter diagram to detect special patterns in the data Determine role of government control in crop prices and input prices
Check dependability of marketing services Investigate land tenure system, check security of system from govern ment officials, legal documents, studies, and extension agents Other (specify)

Crop varieties: Obtain available data from agricultural officials
and available research
Gain information from farmers and extension workers






72


Compose estimates of vie 1 esul s from. leading and average farmers of various varieties of given crops
Other (specify)

Seedbed preparation:
Consult available information from agricultural officials, and research and extension
specialists
Make preliminary field observations of farms and discuss with farmers Other (specify)

Planting/sowing dates: Consult available data aout costs and benefits of optimum versus nonoptimum dates for selected crops
Discuss with farmers their views of optimum versus nonoptimum dates and perceived costs Other (specify)

Seed source, quality
and seed rates: Consult available data on costs of seed from
various sources, benefits of using seed of a known quality, and cost-benefits of optimum seed rates for selected crors Discuss with farmers and extension workers the cost of seed, the availability of quality seed, and the value of certain rates of seed per hectare or acre for selected crops Other (specify)__Fertilizer cost,
availability, use,
and methods of
application: Establish from available data the actual cost to
various farms for fertilizer, degree of availability of fertilizer, the costs, benefits of various levels of use, and costs and benefits of various methods of application Discuss with farmers and extension workers their perceptions of the questions above Other (specify)

Weed and insect control
methods: Establish from available data the costs and
benefits of various control methods Discuss with insecticide agency staff and researchers
Make initial field observations and discuss with farmers and extension workers to determine their perceptions of costs and benefits and the degree of control that should be used Other (specify)






73


ge: Obtain available data from research stations
and other organizations
Discuss with farmers and extension workers and estimate the losses in production to all farms due to crop damage Other (specify)

:ions: Consult research station personnel and farm
machinery companies about benefits of alternative methods of all tillage operations Observe in the field what different operations are used with what types of implements and machinery
Discuss with farmers and extension workers alternative costs and benefits of various methods
Other (specify)

,t operations: Consult available data to determine the
benefits in terms of actual yields of various methods
Observe operations in the field and join farmers' and extension workers' views of the losses in crop output of various types of harvest operations
Other (specify)

Storage facilities: Consult available data as to crop losses of
various storage methods. Document the types of facilities from farm level to market centers to national storage schemes Discuss with market personnel the relative benefits of various storage systems Observe various storage systems from farm to market center
Discuss with farmers losses from rodents, mold, temperature, insects; and various storage methods for major crops Other (specify)

Market facilities: Consult available data from government offices
and marketing centers
Document modes of farm to market transportation and costs of each
Discuss with farmers the costs of marketing farm products, including costs of middlemen, transportation, and taxes Other (specify)
Credit facilities: Consult available data about sources of credit,
availability, use, and types and terms of credit from credit institutions Discuss with those who work directly with farmers the questions above Other (specify)






74

Table 14. Checklists on detailed diagnostic methods for farm
management practices.

Cropping patterns: Conduct crop survey and enter on map of
each field and season
Interview farmers using a grid system designed for the units used (acres, hectares', etc.). Data collector should verify reports by checking the field individually for certain crops.
Take aerial surveys if possible to do with adequate detail and at proper time. Other (specify)

Irrigation practices:
Conduct field surveys to document the various practices used and reasons why Utilize data from irrigation engineers to document the actual losses of water and costs of that water
Utilize data from engineers and agronomists to document the influence of the application of too much and too little water, and quality of water on yields
Utilize data from engineers and agronomists to estimate costs and benefits of various methods of improved return flow of water. Other (specify)

Resource inventory/
farm budgets: Conduct a sample survey to check land,
labor, capital, animals, water inventory, and outputs
Other (specify)

Decision-making: Determine prices and yields from direct
observation.
Observe terms Qt tenancy to verify or modify information already obtained. Observe farmers when they are planting, irrigating, cultivating, and caring for their crops.
Note how farmers adjust to problems of uncertainty. Ask questions such as: "What
recourse do farmers have if they lose most of their major crop? Is credit or support easily available through the family? What food reserves do the farmers maintain? What minimum risk crops do they plant? What is the amount of farmers savings (very
difficult to determine)?
Other (specify)

Crop varieties: Document the crop varieties along with
cropping patterns on field maps used by farmers.





75


Crop varieties: Document the crop varieties along with
cropping patterns on field maps used by farmers.
___Analyze the benefits in yields attributed to varietal differences from on-farm data and data at research stations.
Other (specify)

Seedbed preparation:
Conduct farm level surveys to document the benefits and costs of various methods in terms of yields and net farm income. Other (specify)

Planting/sowing
dates: Conduct field surveys with farmers and
acquire data from experiment stations to analyze the reductions in yields resulting from variations in sowing and planting dates for major crops.
Determine if the range of sowing/planting dates for various crops provide adequate margin for farmers in terms of field operations.
Other (specify)

Seed source, quality,
and seed rates: Conduct farmer interviews to determine source
of seed, availability, and quality of seed. Obtain data from experiment stations about seed quality and variations in yields resulting from various levels of seed rates. Establish the economic levels for various seed rates in relationship to yields. Other (specify)

Fertilizer costs,
availability, use and methods of
application: Conduct farmer survey to determine the costs
of fertilizer, availability at time needed, credit availability, rates applied, and methods of application.
Compose recommended levels of fertilizer and methods of application for selected crops from research stations and farmers' practices. Compare project field data with that of fertilizer companies.
Ascertain the economics of fertilizer use by farmers
Other (specify)






76

Analyze the benefits in yields attributed to varietal differences from on-farm data and data at research stations.
Other (specify)

Seedbed prepay ration:
Conduct farm level surveys to document the benefits and costs of various methods in terms of yields and net farm income. Other (specify)

Planting/sowing
dates: Conduct field surveys with farmers and
acquire data from experiment stations to analyze the reductions in yields resulting from variations in sowing and planting dates for major crops.
Determine if the range of sowing/planting dates for various crops provide adequate margin for farmers in terms of field operations.
Other (specify)

Seed source, quality,
and seed rates: Conduct farmer interviews to determine source of seed, availability, and quality of seed. Obtain data from experiment stations about seed quality and variations in yields resulting from various levels of seed rates. Establish the economic levels for various seed rates in relationship to yields. Other (specify)

Fertilizer costs,
availability, use and methods of
application: Conduct farmer survey to determine the costs
of fertilizer, availability at time needed, credit availability, rates applied, and methods of application.
Compose recommended levels of fertilizer and methods of application for selected crops from research stations and farmers' practices. Compare project field data with that of fertilizer companies.
Ascertain the economics of fertilizer use by farmers
Other (specify)

Weed and insect
control methods: Conduct field studies to determine actual
losses in crop yields due to losses from weeds and insects.
Establish the economics of improved methods versus farmers' methods. Other (specify)






77

Other crop damage: Conduct field surveys to determine from
farmers actual cost of losses from animal, natural, and human sources Other (specify)

Tillage operations: Conduct field surveys to determine the capital
and labor costs of major tillage operations. Determine from field surveys the benefits of timely operations.
Determine the recurring costs involved from purchased farm machinery and animal power. Other (specify)

Harvest operations: Document in field surveys the costs of all
operations and the value of timeliness in operations.
Compare the costs and benefits provided by equipment salesmen and farmer users. Include in field studies the seasonal availability and costs of labor
Other (specify)

Storage facilities: Obtain data at the farm level about estimated losses of crops in farm level storage Obtain data from market centers and other storage centers as to losses in storage and calculate a total loss due to inadequate storage facilities
Compare the costs and benefits of alternative types of storage facilities and practices. Other (specify)

Market facilities: Conduct farm level and market center surveys to determine costs of transportation, middlemen, and levies to the farmer. Compare costs of various types of marketing practices in which farmers are involved. Other (specify)

Credit facilities: Conduct field surveys to document source of
credit, type of credit, and costs of both institutional and noninstitutional credit to the farmer. Also, ascertain credit availability to all classes of farmers.
Obtain information on credit availability and terms of credit from both institutional and noninstitutional sources. Estimate the need for productive versus consumptive credit needs for all classes of farmers.
Other (specify)





78


included in the resource survey. A map is also useful to help
summarize all of this data and for suggesting representative farm groups.


Labor

Information should be collected on age, sex, health, number, and education of family laborers. Also, it is important to know the tasks performed by various family members and the availability of hired labor. It is necessary to know the terms of hiring, the calendar availability of off-farm work for laborers, and the wages to be paid.


Capital

Several questions should. be answered such as What are the financial sources? Is it the* farmers own savings or credit? If it is credit, where. was it. obtained? Was it obtained from family, a money lender, farmers,I a cooperative, a bank, the government? How much does each farmer pay and under what- terms? What is the interest rate, repayment schedule, and security?


Animals

An inventory of all animals, either raised for food or work should be assembled. The animals' condition, consumption requirements, market value, labor required to keep them, and susceptibility to disease should be noted.


Water Inventory

The availability of water at specific times, and other inputs required to use it, including labor, machinery, and animal inputs should be checked.


Outputs

Each crop should be inventoried according to its yield, its requirements for .specific timing of inputs, the cash costs of inputs, and the prices on outputs.






79


Decision-Making Environment

Individual farmers do not allocate their resources independently of their neighbors; rather, they are part of a complex web of obligations connecting them with their neighbors and relatives. Farmers also
depend on average or normal returns such as those derived in the representative farm budgets. The farmers are subject to extreme variations in yields resulting from causes beyond their control such as rainfall, disease, pests, sickness, market changes, and political
changes. Both competition between farms and variations related to prices and other variables influence the individual farmer's decisionmaking framework. Therefore, these factors need to be carefully considered to understand basic causes of farm production problems.


Interdependency with Farmer's Community

A thorough study of farm management practices along with data on crop potentials allows investigators to construct: (a) representative farm budgets reflecting what farmers actually do, and (b) alternative budgets reflecting what they could do, either with existing resources or added factors. However, the farmer's real choices are strongly conditioned by factors that are difficult for researchers to comprehend, let alone quantify. These include uncertainty and obligations with neighbors and relatives and the farmer's village environment as a whole, which is the topic of Chapter VI.


INTERDEPENDENCY OF FARM MANAGEMENT PRACTICES WITH WATER
SUPPLY AND REMOVAL SUBSYSTEMS

As a means to show how farm management practices are closely related to the water supply and removal subsystem, a hypothetical case is utilized. It is assumed that crop stands on a farm are very poor and limiting production. The agronomist investigates and discovers that in both leaf tissue tests and analysis of soil samples there is a definite nitrogen deficiency. The farmer reports, however, that he applied the recommended rates of nitrogen. In turn, the hydrologist locates a high water table resulting from poor drainage. Later, from measurements of water losses from poorly maintained field channels and overirrigation, it was found that irrigation efficiencies are only 25-30 percent. Also, it




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was discovered that 40-50 'percent of the nitrates applied were leached through the soil profile to groundwater. Further interviews with the farmer revealed that he applied what water he could every week when water was allotted on a fixed rotation system. It was learned that the farmer applied all the water he could to his fields because of (a) lack of knowledge of the appropriate amount to apply, and (b) concern that canal supplies might not be regular.
In such a case, the investigator must be careful not to confuse symptoms of problems with causes. Also, the investigator must learn to search for multiple causes. For example, if the problem is defined as poor crop stands, nitrate leaching and poor drainage are only symptoms. The causes of the problem may be overirrigation resulting from both lack of knowledge and a rigid and unreliable irrigation rotation system. Many irrigation symptoms such as waterlogging have been treated at a great cost to farmers and the public while the real cause of the problem was the behavior of the farmer which, if corrected, would have resulted in long-term improvements at lower costs.






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CHAPTER V


WATER SUPPLY AND REMOVAL


The water supply and removal subsystem includes the supply of water from all sources for the farm system, delivery of water to farms, and removal of water through the drainage system. Water supply
involves climatic data including rainfall and rainfall distribution, solar radiation, air temperature, relative humidity, wind speed, and other factors that influence the total amount of water made available to the farm system. In addition, climatic data includes information about hazards such as excess supplies of water from flooding (Figure 11).
Water supply and delivery is the conveyance of water from the supply source to the farmers' fields. Water removal is the removal of excess surface or subsurface water.
The institutional arrangements related to water supply and removal are included in Chapter VI. Special attention is given to several critical dimensions of the total area served. For example, topography, land capability, and location of structures are included. These dimensions may require development of detailed maps.


CLIMATE

Climatic Data

Most countries maintain some weather stations. It is preferred
that weather data are to be obtained from stations in close proximity to the irrigated area. Types of data needed for collection include solar radiation, air temperature, relative humidity, wind speed, open-pan evaporation, and rainfall distribution.


Solar Radiation

Radiation from the sun not only furnishes energy for photosynthesis, but is the primary source of heat for air and soil. Solar radiation is sometimes measured as part of basic climatological data. The basic measurement is generally recorded as calories/cm2 of










Canal

Water SupplyCmadAe
-Source-Tpgah
-Precipitation -adcpblt

-Surface flow -rpigpten
-Groundwater-FedadBsniz
-Conveyance -Location of structures
-operational control -General features
-flow characteristics -wells
-water losses -pumps
-farm inlet deliveries -roads
-maintenance -farm building

C lommandiArea







-worocrwgrDranag
-Land capbiit
Labor~~Crppn patternsne atrReovl

Local~-Lcaio fctce structrrae 'Ln

-work rews -wellsg









-water trading -surface
Cooperatives -Subsurface
Mutual aid

Figure 11. Idealized sketch of a farm irrigation water supply and removal subsystem.






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incident radiation over a period of time and is generally reported as monthly or seasonal mean values. Solar radiation data are primarily used for calculation of evapotranspiration by various crops.


Air Temperature

Basic climatic data measured daily are maximum and minimum temperatures, and are logged as mean as well as maximum and minimum temperature. These data are usually summarized into weekly, monthly, seasonal, or annual values. The data are needed to determine appropriate growing seasons for crops in terms of time periods with temperatures above a minimum and below a maximum, or in terms of frost-free days. Temperature data are used to calculate growing degree days (heat units) from daily temperature and are accumulated daily for particular crops. For example, adjusted growing degree days (GDD) for corn (maize) are calculated as the sum of mean temperature
-50 0F for each day. When calculating the mean temperature for a day, any minimum temperature below 50 0F (10 C) is counted as 50 and any with a maximum above 86 0F (30 C) is counted as 86. A day with 44 and 80 would have (50+80)-50=15 GDD or heat units. A day with 60 and 94 would have (60+86)-50=23 GDD or heat units. Corn hybrids and some other crops tend to mature according to heat units produced rather than an exact number of days. This adjustment process allows for some vegetative growth in corn when temperature is above 500F only part of a day, with the best corn growth being at 860F with growth beginning to taper when it is greater than 860F. Air temperature data are used along with other climatic data to estimate evapotranspiration for various crops.


Relative Humidity

Basic climatological data usually include measurements of relative humidity. This is done by wet and dry bulb temperature determinations or with a recording hygrometer. Relative humidity is one of the determining factors in calculating evapotranspiration directly, or estimating pan evaporation indirectly.




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Wind Speed

Wind speed is measured with an anemometer and is usually recorded as accumulated miles or kilometers per day and summarized with other climatic data. Information on direction of prevailing wind should be also noted.


Open-Pan Evaporation

These data are usually not included in standard weather measurements but are collected within the irrigated area under study.


Rainfall and Distribution

Rainfall is usually measured once a day with a standard rain gauge and occasionally with a continuous-recording gauge. Data from a continuous-recording gauge is especially useful for giving information about rainfall intensity. The data are usually summarized by month or by a particular cropping season. Data can be plotted to show the distribution of rainfall through a particular cropping season or throughout the year. Data over several years can be used to calculate probability of occurrence statistics that are useful for determining irrigation requirements.


Weather Observation Stations

If sufficient climatic data are not available, it may be necessary to establish a network of observation stations in a particular irrigation area. These stations can be used to gather data for determining water supply problems, groundwater recharge problems, irrigation requirements, and crop adaptation problems.


Water Supply Problems

Data needed to predict yearly water supplies usually consists of rainfall or snow depth, water content, and temperature measurements to predict amount and time of runoff.