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Tropsoils Project - Indonesia (Soil Management CRSP)

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Title:
Tropsoils Project - Indonesia (Soil Management CRSP)
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University of Hawaii
North Carolina State University
Center for Soil Research
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University of Hawaii; North Carolina State University; Center for Soil Research
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Language:
English

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Subjects / Keywords:
Farming ( LCSH )
Agriculture ( LCSH )
Farm life ( LCSH )
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Asia -- Indonesia

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Electronic resources created as part of a prototype UF Institutional Repository and Faculty Papers project by the University of Florida.

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Full Text
TROPSOILS PROJECT INDONESIA
(SOIL MANAGEMENT CRSP)
February 1987




TROPSOILS PROJECT INDONESIA (SOIL MANAGEMENT CRSP)
FUNDING AGENCY
U.S. Agency for International Development, Washington, D.C. DATE STARTED: June July 1983.
COLLABORATING INSTITUTIONS.
1. University oi Hawaii (lead institution).,.
2. North Carolina State University (support insitution;
active participation ended July 1986).
3. Center for Soil Research, Bogor, Indonesia.
RESEARCH SITE: 20S, 101 E (see location maps, p. 2-3)
Sitiung, West Sumatera, Indonesia; approximately 210 km SE of Padang. Time to travel: 5 hours by car and 7.5 hours by public transportation.




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5
SITIUNG AGRICULTURE: Most transmigrant families are engaged in raising field crops. Field work is mostly done by hand. Common crops are rice, corn, soybean, peanut, cowpeas, cassava, and mungbeans. Vegetables and fruits are grown in the home gardens. In the newer settlements, a major portion of the farm produce is for home consumption.
Javanese and Sundanese farmers usually till the land and like to see it clean of weeds. The indigenous minang farmers, on the other hand, employ no-till farming practice. Most farmers know the value of lime, fertilizers, and pest control chemicals, but few can afford to use as much as they would like to.
Crop yields are generally low to very low, but can be improved with sound management. The following table presents a comparison of crop yields under low and high input management systems.
YIELD, t/ha
CROP
Low input High input *
Upland rice 0.7 2.5
Corn (monoculture) 2.0 5.5
Corn (corn + rice) 0.11
Soybean 0.3 2.0
Peanuts 0.6 2.0
Cowpeas 0.6 1.5
Mungbeans 0.0 1.0
Experimental yields
CONSTRAINTS TO PRODUCTIVITY*
Researchers' PerceRtion Farmers' Perception
1. Poor soil fertility 1. Poor soil and climatic
2. High soil acidity and conditions.
aluminum saturation 2. Inadequate labor
3. Moisture stress 3. Shortage of cash
4. Soil variability 4. Marketing problems
5. Soil erosion 5. Poor extension services
6. Poor supply of agricultural 6. Government policy
inputs 7. Lack of irrigation works
7. Poor genetic stock 8. Pests and diseases
8. Poor quality seeds
9. Pests and diseases
* These are not ranked in order of importance




7
The anticipated project team will include Ron Guyton (senior agronomist), Lalit Arya (senior soil physicist), Carl Evensen (junior.agronomist), Stacy Evensen (nutritionist), Stephenie Kan (junior agricultural economics graduate student), unnamed senior farming systems researcher with interest /experience in extension, and an unnamed junior agroforester. Changes and additions may occur due to funding uncertainties, and the unavailability of new team members to participate in this planning process.
The following six major categories summarize our Indonesian on-site program. Rationale, activities, and personnel requirements are listed for each:
1. Liming and Soil Fertility
Liming
Various lime trials have been done in Sitiung. The initial results have been consistent with published information regarding soil acidity on similar soils in other parts of the world. However, there is a noticeable lack of long term lime studies on soils in Indonesia, as well as in the humid tropics in general. Now we have the opportunity to study long term aspects of liming as indicated below:
Maintenance: Studying annual lime application for maintaining an
established or desired level of acidity.
Residual: Duration or length of effectiveness of a single application.
Downward Movement of Ca into the soil profile and its effect on crop
growth.
Effectiveness of lime on various soil types.
Soil Fertility
Phosphorus: The studies on phosphorus have consistently indicated a very strong response to P fertilizer on previously unfertilized soils, but relatively




8
low rates of both initial and maintenance applications have been sufficient to establish and maintain plateau crop yields. A more indepth look at the maintenance or longterm phosphorus fertilizer requirements needs to be done. Also, experimentation of the interaction of phosphorus with lime has recently been initiated and should be continued.
Potassium: There has been a remarkable response to K fertilizer on
Sitiung soils, requiring high rates and frequent applications to provide plateau yields of most food crops. Apparently potassium leaches very rapidly from the soil and at least one study (effect of organic materials on the replenishment of potassium and curtailment of leaching) should be continued. Conservation of potassium will be critical to establishing viable and continuous crop production.
Micronutrients: No experimentation has been initiated to date by TropSoils on micronutrients. We have not witnessed any identifiable deficiencies in either our research plots or farmer fields. However, a survey of plant tissue from various locations and crops would help establish the general micronutrient status of the soils and relevance of future research on that subject.
All of the above topics will provide experimental data that can be used by the CSR soil testing program, led by I. P. Gedjer Widjaja-Adhi, to help establish valid indices for making lime and fertilizer recommendations, using an expert system. The established trials will be supervised by Ron Guyton, and new trials will be done in collaboration with anticipated new CSR personnel.
2. Soil and Water Conservation Work to date by TropSoils has illustrated that soil moisture shortages, soil erosion, and excessive runoff are serious problems in West Sumatra. Despite 2500-3000mm of annual rainfall, crops suffer from moisture stress that eventually results in serious reductions in yields.




9
Crop roots appear to be confined wi-n in the depth of tillage, which is manually performed with a hoe to a depth of ten to fifteen cm. This shallow rooting depth reduces the amount of water stored in the soil that is available to the plants. Thus, crops cannot utilize any of the soil moisture stored below a depth of 6 inches. There is reason to believe that a further major restriction to root development is the presence of toxic levels of aluminum below the depth of tillage and, therefore below the depth of lime incorporation. Neutralizing soil acidity creates favorable conditions for root growth and a favorable chemical environment for nutrient availability
Soil moisture storage is affected by internal drainage conditions.
Although the West Sumatra soils are clayey, many of them are composed of stable aggregates. We believe that much of the infiltrated water rapidly drains below the root zone. It may be possible to alter the soils structure to impede this internal drainage,. thus increasing soil moisture storage in the root zone.
On the steeper cultivated slopes, excessive runoff and soil erosion occur quite easily. A large portion of the rainfall that otherwise could be stored in the soil profile is lost to runoff. 'Continued removal of topsoil, which holds the limited amount of plant nutrients results in a serious decline in productivity. The problem is most serious for resource-poor farmers because they cannot easily replenish the lost nutrients and other inputs to restore soil productivity. It is imperative that management practices developed for farmers in this region be conservation-effective practices in order to sustain economic crop production in this humid environment.
During 1986-1987, the major focus of research will be oriented toward the following objectives:
DetermininC, the extent and rate of downward movement of lime and the
effect on root development and water absorption;




10
- Characterizing the available water retention properties of soils in the
Sitiung area;
- Investigating the effect of residues, both surface and incorporated, on
water retention and soil losses;
- Exploring the potential of various conservation effective farming
systems; and,
- Investigating the effects of current and revised tillage practices on
soil and water -conservation.
Anticipated non-CSR personnel involved in this project will include Lalit Arya and a junior scientist. Involvement by the farming systems researcher in the study is expected.
3. Organic Material and Forage Management The marked response of some crops to green manure in previous experiments in Sitiung has suggested that the proper management of organic materials might reduce the need for lime and fertilizers on Sitiung farms. Also, the importance of livestock and difficulties in finding adequate feed has suggested the need to assess more productive forage systems. A series of experiments has been initiated in Sitiung to 1) quantify the influence of green manures on crop yields, 2) evaluate fertilizer and herbaceous legumes and forage grasses for use on transmigrant farms, and 3) to incorporate information from Sitiung transmigrants in the selection and design of green manure and forage management systems. These are:
Alley Cropping: There is presently one experiment being conducted to
determine-the green manure and wood productivity of three legume trees at three levels of lime application and their influence on intercropped food crops.
Source and Application-Method of Green Manure: Two experiments are
being conducted to compare methods of production and application of two species of herbaceous legumes.




11
Forage Crop Evaluation: Two experiments are underway designed to select promising forage and green manure species and determine their fertilizer requirements.
Compost: A farmer-managed experiment is being conducted in Sitiung home gardens to compare crop response to compost, farmyard manure, inorganic fertilizers and fishpond sludge; and to assess the interest of farmers in these different fertilizers and amendments.
0
Carl Evensen and Russell Yost in Hawaii are the primary researchers in
this series of experiments. For the composting trials, Carl will be assisted by Stacy Evensen and the farming systems researcher.
4. Agroforestry The farming system of the indigenous population of Sitiung includes shifting cultivation which culminates in tree crops (rubber, coffee, fruit trees). A variety of tree crops are also grown on transmigrant home gardens. The appropriateness and advantages- of -tree crops in the Sitiung environment are now obvious, including tolerance to soil acidity, reduced risk of pests, soil conservation, more effective use of available soil moisture, more reliable cash incomes, and lower human labor requirements. It appears that the development of improved soil management practices for field crops alone will i) not result in a satisfactory income for transmigrants, and 2) is not consistent with the farming system of the indigenous population at all. The following activities have high priority:
Legume Tree Evaluation: This experiment has been undertaken in
collaboration with NFTA, investigating the nitrogen contribution of these leguminous trees, and assessing suitability for the Sitiung environment.
Food-Tree Intercrop: Ideally a whole series of experiments would be
initiated which use these kinds-of crop mixtures. Such experiments could focus on soil fertility, soil biology, soil physical and/or conservation questions.




12
leguminous trees, and assessing suitability for the Sitiung environment.
Food-Tree Intercrop: Ideally a whole series of experiments would be
initiated which use these kinds of crop mixtures. Such experiments could focus on soil fertility, soil biology, soil physical and/or conservation questions.
The legume tree evaluation is being undertaken by Carl Evensen. The planned agroforestry graduate student would be responsible for the series of experiments called "Food-Tree Intercrop". This would be an ideal context in which to collaborate with another institution such as the Horticulture research station in Solok, the Abai Siat Rubber Replanting Project in the Sitiung area, or the NES coconut project in Rimbo Bujang.
5. Extrapolation Soil management research on infertile, strongly acid, Red Yellow Podzolic soils of Indonesia by the TropSoils Project has uncovered three major soil constraints that restrict crop yields. These are aluminum toxicity, and severe phosphorus and potassium deficiencies. Project personnel have developed a computerized expert system that enables extension agent to make recommendations to neutralize toxic aluminum with lime or organic matter. The research on phosphorus shows that although the soils are severely deficient in this element, the problem can be corrected with relatively low initial, and still lower maintenance, rates. In the case of potassium, rapid leaching of this nutrient from the root zone into the toxic subsoil renders this element more difficult to manage in these soils than similar clay soils elsewhere in the world. Research, however, proves that lime and organic matter improve the potassium fertilizer use efficiency by crops.
This two part activity is designed to test the technical, economic and social suitability-of TropSoils research findings in farmer fields.
The first part consists of testing the accuracy of the lime rates
recommended by an expert system, and establishing the range of transferability




13
of the low phosphorus fixation rate, the high potassium leaching rate and the effectiveness of green manure to counter the toxic effects of aluminum in acid, Red Yellow Podzolic soils of Indonesia. In addition, efforts will be made to incorporate the diverse kinds of social science input into an expert systems designed to predict the crops likely to be grown.
In line with the farming systems approach being utilized, the technologies and systems identified as promising must be tested under farmer conditions. A tentative set of "Best Management Practices" has been identified and the process of testing the systems will be initiated. Similarly, two or three "special
studies" on aspects of the farming systems can be expected, dictated by observations and information needs of the team. One, year-long study that will be completed is the characterization of home gardens. An enterprise record keeping study is being initiated and will be partially completed during this year.
The work in Sitiung will be carried out with the assistance of local
extension agents. To do so, appropriate contacts with extension officials and provincial administrators will be required.
In addition, the project will require the services of an economist to evaluate the benefits that accrue to users of the technology. The Farming Systems Researcher will evaluate farmer reactions to the innovation and t he likelihood of their retaining the technology, as well as providing ongoing feedback to other members of the team on matters related to farmer acceptance of technology. Continued support is anticipated from Perry Philipp, Hal McArthur, Kathy Wilson, and Carol Dixon at the University of Hawaii.
The development of the decision support system will continue at the University of Hawaii, under the leadership of Coro Uehara, Russell Yost and Steve Itoga.




14
6. Linkages -The goals and objectives of TropSoils are closely related to these many other programs and institutions in Indonesia. The total accomplishments of these programs can be increased by periodic interaction to share relevant information, and by working collaboratively where mutually
beneficial results can be achieved. Since its beginning in Indonesia, TropSoils has had a highly beneficial collaborative relationship with the Centre for Soil Research. However, there appear to be additional opportunities to. add to this success.
As a means to initiate these actions, the following are suggested:
a. Continue the major collaborative effort with the Centre for Soil
Research in the same manner as has existed from the beginning of the
program.
b. Appoint, a joint committee to devise a plan and promote the
extrapolation of current technology on the proper use of lime. The
composition of the committee would include a representative from CSR,
one from Extension and one from TropSoils.
C. Initiate an exchange of the Annual Work Plans between the TropSoils
program and the SARIF program in Sitiung.
d. Conduct and annual joint meeting to review the accomplishments of each
program during the past year, and the plans for activities during the
coming year.
e. Maintain a sensitivity to the opportunities which may arise for
collaboration with other institutions which could be mutually
benefici al.
7. Constraints Major constraints to accomplishing the activities identified above, in addition to uncontrollable environmental factors, are personnel staffing and adequate funds for operations.




15
The level of funding from TropSoils to support operating expenses, is most uncertain. This is due in part to the uncertainty of actions by the U.S. Congress and in part to the competing demands for TropSoils funds from components of the program in other countries. While every effort will be made by the Management Entity to maximize the funding for TropSoils Indonesia, substantial additional support will be required to conduct fully the activities set forth above.
4




16
ONGOINGRESEARCH ACTIVITIES
1. SOIL FERTILITY
a. Lime reaction
- crop response
- residual effect
* maintenance
b. Phosphorus
- Crop response
- critical levels
- maintenance
- lime X phosphorous model
- rock phosphate vs. TSP C. Magnesium
- crop response (rice-peanut; maize-soybean)
- maintenance
d. Fe-toxicity: fertility management
to eliminate "orange disease" in
flooded rice.
e. Effect of calcium and molybdenum on
productivity of forage legumes
f. Nitrogen sources
2. VARIETY SCREENING
a. Peanut screening for
acidity tolerance
3., ORGANIC MATERIAL AND FORAGE MANAGEMENT
a. Alley cropping
-effect of lime X tree species




17
b. Green manure management
- source of GM, method of application, liming rates
c. Tree legumes
d. Forage legumes and grasses
4. SOIL PHYSICS AND EROSION/CONSERVATION
a. Root growth problems
- Aluminum toxicity and liming Effect of organic amendments
b. Post-clearing management
- organic residue and cover crops
- tillage
- chemical inputs
c. Erosion/Conservation
- evaluation of conservation practices
- bench terrace
- bund terrace
- grass strip
- slot mulch
- bare
5. SOCIOECONOMICS
a. Farmer practice and production study.




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RESEARCH HIGHLIGHTS TO DATE AGRONOMIC
A. LIME
1. Efficiency: lime to achieve 20% acid saturation (Al+H)
(a out pH 5) for most efficient use of lime.
2. Crop tolerance to acid saturation: Mungbean 0 Soybean 15%
Maize 30%
Peanut 40%
Rice 60%
3. Prediction: LR (t/ha) = 1.5 (exch Al+H -(RAS*ECEC))
Where RAS is required acid saturation, ECEC is effective CEC (sum of bases) BD=l.O and tillage is 15 cm
4. Maintenance: approximately 1/3 of initial rate per year
will maintain the established level of acid saturation.
5. Incubation: none required, lime reacts very quickly in
the warm, moist soils of the udic environment.
B. PHOSPHOROUS
1. Soils have low P-fixation capacities despite high clay
and high Fe contents; 20-80 kg P/ha is sufficient to
reach optimum yields.
2. Rates of 10 to 20Tkg P/ha/crop are adequate to maintain
sufficient available soil P.
3. Method of application of P fertilizer is not critical
for agronomic effectiveness but broadcasting has, by
far, the lowest labor requirement.
C. POTASSIUM
1. Under high yield environment, high rates of K are
required to achieve maximum yields.
2. Poor residual effect; should make applications each crop.
3. Rice blast is suppressed with KCl; probably due to CI-.




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D. ORGANIC MATERIAL
1. Newly cleared soils
a. No response to lime despite 50% AS; organic acids
complex Al.
b. Burning increases yields, does not reduce organic C.
2. Green manuring
-a. Alleviated lime response of rice.
b. Improved efficiency of P fertilizer.
c. Alleviated K response.
3. Alley cropping
a. Albizia falcataria and Calliandra calothyrsus prunings
alleviated lime response of rice and improved
fertility.
b. Trees tolerate poor soils and soil acidity.
c. Trees tolerate frequent pruning, i.e. coppice well.
E. SULFUR:
No response to S fertilizers on corn, soybean, or mungbean
on either recently cleared soil or soil cultivated for
5-years.
F. MAGNESIUM: (Initial information)
1. Strong visual response of maize and soybeans
2. Little response of rice and peanut.
G. VARIABILITY:
1. Base status (Ca, Mg, K)- best correlated with variable
growth.
2. Organic C and extractable P not correlated.




20
CROP MODELS AND EXPERT SYSTEMS:
Modeling work has been carried out mainly at the University of Hawaii. A corn model has been tested and validated in Hawaii and Indonesia. An expert system (ACID3B) that mimics the human expert has been developed to make liming recommendations for a variety of soil and crop conditions.
SOCIOECONOMICS
Social scientists (anthropologists, economists, etc) have played a valuable support role in TROPSOILS research efforts. While agricultural researchers have concentrated on specific constraints to crop production (e.g. assessing problems relating to soil acidity), social scientists have taken a broader view. In general, their role has been to assess current farmer practices, the potential for proposed research as perceived by the farmer-user and to provide continuous monitoring and feedback relating to the socioeconomic and cultural aspects of the TROPSOILS research program. Using various methodologies including participant observation, time allocation studies, and farmer record-keeping systems, these researchers have provided the following:
1. A characterization study of ethnic variation in soil
management practices which led to a variety of experiments
on different tillage practices.
2. Documentation of the potential of tree crop cultivation
among the indigenous population fueling TROPSOILS' interest
in agroforestry research.
3. A survey of sources and amounts of household income. This
information allowed researchers to tailor their lime trial
treatment levels to more closely -approximate farmers'
capabilities.
4. Justification for continuation of a forage grass trial via
documentation of time required for local farmers to collect
animal feed.
5. A food consumption survey which provided useful information
about dietary preferences thus enabling researchers to
focus on appropriate crops for experimentation.
These are just a few examples of how an awareness of farmers' traditional practices, -economic and labor capabilities and constraints and farmers' perceptions of proposed technologies has allowed TROPSOILS researchers to more effectively work with and develop technologies for use by local farmers in Sitiung.




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FUTURE PLAN
Tropsoils workplan for 1986-87 was prepared in May 1986. It was developed from considerations of ideas contributed by Center for Soil Research, University of Hawaii, North Carolina State University, Management Entity, U.S. Agency for International Development, and the Indonesian Agency for Agricultural Research and Development. Six major Areas of activity were identified. These were:
1. Liming and Soil fertility.
2. Soil and Water conservation.
3. Organic material and forage management.
4. Agroforestry.
5. Extrapolation/Extension/Socioeconomics.
6. Linkages with other programs and institutions.
Staffing needs were specified for each activity. It was assumed that the funding level would be maintained and the necessary professional staff would be brought in.
Several things have happened since this workplan was developed. Most important is the cutback in the budget that both UH and CSR have suffered. The University of Hawaii Tropsoils budget has been reduced by 49% and that of CSR by about 75% As a result, staff and other material support for the project had to be curtailed. For example, socioeconomics and agroforestry positions have not been filled. We had anticipated that a few graduate students/research associates would join the project in Sitiung. None are expected now. Equipment necessary for initiating new activities have not been made available. CSR has asked its staff members in Sitiung to discontinue some of the experiments.
Moreover, Tropsoils program in Sitiung is in a state of transition. All members of the original American team have departed, except Carl and Stacy Evensen. Stacy plans to leave end of February 87. Carl will leave in June 87. New members, Ron Guyton and Lalit Arya arrived in Sitiung 5 to 6 months ago. Ron is a forage agronomist. He is supervising the soil fertility experiments left in progress by Mike Wade. He is also supervising maintainence and repair of equipment and vehicles. Lalit is a soil physicist. He is responsible for developing and implementing a research program in soil physics and soil and water conservation. Lalit is also the current team leader and has many administrative and supervisory responsibilities.




22
Progress has been slow because of a number of factors (listed under factors affecting progress). All of the activities envisioned in the 1986-87 workplan have not been implemented. At the present time, it seems that Lalit Arya and Ron Guyton will be the only two American staff in Sitiung. There is a
possibility that CSR will call back some of its B.S. level staff and locate them elsewhere.
Future plans for Tropsoils research must, therefore, consider the above circumstances. The team in Sitiung has had several discussions and feels that 1986-87 workplan addresses soil management issues that are relevant to Sitiling as well as to other humid tropical regions. The team does not see how a future workplan would be any different from the current plan. In other
words, the current workplan should continue to provide the guideline for activities in the immediate future. There is need, however, to consider the many constraints that the project is facing and prioritize the activities.
The team recommends the following research activities.
AGRONOMICS
1. New liming trials should be initiated with emphasis on
monitoring the movement of calcium with depth and time for several rates of lime application. These trials should also attempt to establish the effective root zone of different crops and how it is affected by liming.
Leaching losses of calcium must be determined. Include in these experiments the observations of residual effect of applied lime on crop yield. It would be desirable to establish one trial of this type on each of the three
major soil types.
2. Past studies on phosphorus have shown little effect of
phosphorus without lime. Very little growth was obtained
if no lime was applied. It is therefore recommended that only phosphorus X lime experiments be continued. It may
be- desirable to expand the trial to include the three
major soil types.
3. Studies on soil potassium have shown a dramatic response
of crops to applied potassium. Again, all responses were
obtained in presence of lime. Potassium is known to leach out of the soil fast. It would be desirable to initiate trials that would establish the rate of leaching and the residual effects of applied potassium. An investigation of the effects of organic materials on replenishment of K
and curtailment of leaching should be initiated.




23
4. Investigations of root growth problems in Sitiung soils.
Both the mechanical and chemical limitations should be investigated and indices established to recommend ameliorating treatments. This study may be carried out in conjunction with # 1. Field investigations should be
supplemented by laboratory and greenhouse measurements.
5. Characterizing the hydrologic properties and processes in
Sitiung soils. Despite 2700 mm annual rainfall, and hiah clay content in Sitiung soils, crop failures due to
moisture stress are quite frequent. The reports are based
on visual observations only. Most investigators suspect limited root growth. Some suggest excessively rapid internal drainage as the cause of low moisture retention.
No studies have ever been conducted to reveal the real nature of moisture limitations in these soils. The
proposed investigation would quantify soil properties that govern moisture retention and depletion. It would produce information on extractable soil moisture, crop moisture
use, and losses due to evaporation and internal drainage.
Results of these investigations along with those of the investigations of root growth problems will form the basis for recommending water management practices or initiating appropriate new research. Information produced
will also serve as inputs to crop simulation models.
6. Sitiung farmers know the value of chemical inputs, but
only few can afford them. Those few who can, will generally consider only low rates of lime and fertilizer.
Therefore, alternatives to chemical inputs inust be investigated. Marked response of some crops to green manure, recorded in previous experiments, suggests that proper management of organic materials might reduce or eliminate the need for lime or fertilizers on Sitiung farms. Trials need to be initiated to develop cropping and soil management systems in which adequate organic residue is produced and returned to the soil, in a manner most convenient to the farmer. Combinations of residue
management, tillage, and low levels of chemical inputs should be evaluated ,as alternatives to high input chemical management or conventional' clean cultivation with
little or no chemical inputs.
7. Soil erosion and runoff have been viewed as serious
problems in the Sitiung area. Efforts should begin to explore the potential of various conservation effective
farming systems.
S. A new area to be added to the Tropsoils program is variety
screening for acid tolerance. The criteria for selection may be crop yield or root growth response to levels of aluminum saturation. Here's an opportunity to collaborate
with the Food Crops Research, Sukarami.




24
CROP MODELS AND EXPERT SYSTEMS:
Field experiments are expensive and often do not combine more than a few variables. Outcomes are also uncertain due to uncontrollable factors. Simulations overcome these difficulties and are able to predict crop performance in a variety of
situations. Work has been in progress in Hawaii on crop simulation models and expert systems. Testing and validation of these models require data on weather, crop phenology, and soil characteristics. Efforts should begin to produce complete and reliable data sets expressely for the purpose of testing and validation of simulation models and expert systems. Again, there is an opportunity for the Food Crops Research and the Tropsoils project to work together in this effort.
SOCIOECONOMICS:
Farmer practice information produced through the farmer practice and production study carried out by Mrs. Stacy Evensen has been most relevant and useful. This must continue. However, the future of this effort remains uncertain, as Stacy plans to leave end of February 1987, and a replacement for her has not been thought of.
EXTENSION:
It has been suggested that Tropsoils engage in extension
activities. But Tropsoils does not have the expertise that are needed. Furthermore, soils information alone may not form an appropriate extension material.
Tropsoils and Food Crops Research may work together to combine soils and crops information to produce agronomic packages for important crops in the region.
The process of extension will, however, require involvement of an agricultural education and communications expert. Such an expert is unavailable. Local extension agents may be invited to participate in this effort. However, it is for the heads of the concerned programs/institutions to decide how best to approach the issue relating to extension.




25
TROPSOILS STAFFING PATTERN
NAME/AFFILIATION POSITION DATE DATE
ARRIVED DEPARTED
EX PATR'I ATE STAFF
Dr. Lalit M. Arya/UH Team Leader 9/86
Soil Physicist
Dr. Ronald F. Guyton/UH Agronomist 8/86
Mr. Carl I. Evensen/UH Research Associate, 10/84
Ph.D Candidate,
Agronomy & Soil Science Mrs. Stacy Evensen/UH Research Associate, 10/84
Nutrition
Dr. John R. Thompson/UH Team Leader 7/83 12/85
Agronomist
Dr. Mike Wade/NSCU Soil Scientist 7/83 7/86
Dr. Carol J. Colfer/UH Team Leader/Farming 7/83 7/86
Systems Specialist
Mr. Dan W. Gill/NSCU Ph.D Candidate 6/84 6/86
Soil Science
Dr. Richard G. Dudley Consultant in Fisheries 2/86 6/86
Biology
Ms. Stephenie Kan Agric. Economics 4/86 11/86
Univ. of Florida M.S. graduate student
Ms. Ellen Veger Anthropology 8/86 11/86
Univ. Amsterdam Graduate student
IND 0 NESIAN STAFF
Mr. Sholeh/CSR Site coordinator 10/86
(Soil Scientist)
Dr. IPG Widjaja-Adhi/CSR Site Coordinator 10/85 9/86
Soil Scientist
(Now country coordinator)




26
Ir. Fahmuddin Agus/CSR Junior Soil Scientist 7/84 Ir. Sidik Talao'hu/CSR Junior Soil Scientist 9/85 Ir. Ida Bagus Aribawa/CSR Junior Soil Scientist 7/85 Ir. Cuk Sugyarso/CSR Junior Soil Scientist 8/86
Endang Hidayat/CSR Field technician 7/84
Mulyadi/CSR Field technician 7/83
Ir. Bujang Rusman M.S. Soil Scientist 9/86
Univ. Padjadjaran Ph.D Candidate
Ir. Kasli M.S. Soil Scientist 9/86
Univ. Padjadjaran Ph.D Candidate
Opan Sopandi/CSR Field technician 7/84
Rum Harayitno/CSR Field technician 7/83
Sarjiman/CSR Field technician 8/83
Martono/CSR Field technician 7/83
Asda Wijaya/CSR Field technician 4/85
Suwandi/CSR Field technician 8/83
Jamalinal/CSR Field Technician 8/84
Sartini Lab technician 9/86
Wagino/CSR Lab technician 10/84
Ratno GM/CSR Driver 9/83
Ratno SI Driver 12/83
Adi Nagoro Driver 4/85
Tarmin Driver 6/85
Sukirno Driver 11/84
Sugeng Field Asst. local 8/84
Wakidi Permanent Laborer 10/85
Haryono Permanent Laborer 1/86
Maryono Permanent Laborer 7/83
Madio Permanent Laborer 7/83




27
Lasmi Permanent Laborer 8/82
Lasyem Permanent Laborer 4/85
Khairul Munir Project Secretary 2/85
Dr. Joko Santoso/CSR Site coodinator 7/83 6/84
Soil Scientist
Dr. Soleh Sukmana/CSR Site Coordinator 7/84 9/85
Soil Scientist
Ir. Al-Jabri/CSR Soil Scientist 12/84 7/85
Ir. Karim Makarim/BORIF Soil Scientist 5/83 5/85
Ph.D Candidate
Ir. Heryadi/CSR Junior Soil Scientist 9/83 .3/85
Ir. Edi Santoso/CSR Junior Soil Scientist 2/83 9/85
Ir. Agus Sofyan/CSR Junior Soil Scientist 9/83 5/84
Ir. Edi Joniarta/CSR Junior Soil Scientist 10/85 3/86
Ir. Tory Budiastoro/CSR Junior Soil Scientist 9/83 6/86
Herman Agus/Andalas Univ. Junior Ag. Economist 1/85 7/85
Ir. Wicahyono/CSR Junior Soil Scientist 1/84 2/85
Kasno/CSR Lab technician 7/83 5/86
Kasmini/CSR Lab technician 1/84 5/86
Atin S/CSR Field technician 8/82 9/83
Gunawan/CSR Field Technician 8/82 1/84
Yusup Driver 9/83 6/86
Sapar Driver 11/84 3/85
Gusnawardi Driver 4/83 8/83
Sunardi Driver 1/84 4/84
Johansyah Project Secretary 8/84 11/84