sity of Florida
!.h a t t h-ev'U '
S\ arer i Florida's most precious resource. We depend on a clean,
Reliable supply of wvarer, not only when we turn on the faucec
but as [he foundation of our economy. The state has more than
1,-00 rivers and streams that flow for aJmost 52.000 miles, more than "."OO-
lakes covering about 1.6 million acres. -.460 square miles of estuaries and bays,
and more than -001 known springs all oF shich support diverse habitats,
plants and animals, as well as food crops, industry and recreation. In addition.
Florida's enormous underground aquifer system supplies potable iarer to most
of the population.
With almost I- million people, Florida is currently the fourth most popu-
lous state and it continues to grosw rapidiv. within n the next 20 years, the state's
population is expected to increase by more than million people. A recent
report by the state Department of Environmental Protection cited the pressures of this growth and its
accompanying development as serious threats to the state's warer resources. The report noted [hat issues
of water qualirv and quantity are inextricably linked, and maintaining both is critical to a susaiinable
economy and healthy environment.
The University of Florida has a long history of state, national and international research into and
outreach on %iater-related issues. Dozens ot UF researchers in areas as diverse as engineering and lav, are
studying the physical, chemical and biological processes of various aquatic s\srtems and the water man-
agement policies that affect these systems and the people who use them.
Earlier this year, the university officially established the Water Institute, a focal point for UF's
water-related research and education and an entry point for outside stakeholders seeking -ater-related
This issue of Explore highlghts just a small portion of the hundreds of water-related research prol-
ects under way at the University of Florida. The university has been a leader in using science to better
understand social, environmental and economic impacts on Floridas water resources, and vwe intend to
continue that commitment in the future through the after r Institute.
We publish Explore to keep the citizens of Florida and beyond ir.formed about the valuable research
at the University of Florida. We welcome your feedback on these research endeavors.
Vice President for Research
About the Cover
Embraced by the Light by celebrated Florida nature
photographer John Moran captures a diver in Blue Hole
Springs at Ichetucknee Springs State Park. More of Moran's
photos can be found at www.johnmoranphoto.com or in
Journal ofLight, recently published by University Press of
Dr. Bernie Machen
Dr. Win Phillips
Vice President for Research
Board of Trustees
Carlos Alfonso, Tampa
C. David Brown, Orlando
Courtney Cunningham, Coral Gables
Roland Daniels, Gainesville
Manny A. Fernandez, Fort Myers
Joe Goldberg, Gainesville
W.A. "Mac" McGriff III, Jacksonville
Joelen Merkel, Boca Raton
Dianna Fuller Morgan, Orlando
Cynthia O'Connell, Tallahassee
Earl W Powell, Miami
Kim Tanzer, Gainesville
Alfred C. Warrington IV, Houston TX
Explore: Research at the University
ofFlorida is published by the Office
of Research & Graduate Programs
at the University of Florida. For
more information about the
research program, contact Vice
President for Research Win Phillips,
D.Sc., 223 Grinter Hall, Box
115500, Gainesville, FL 32611-
5500. Phone: (352) 392-1582. For
details about research highlighted in
this issue, contact the editor or the
The publication of Explore is
not financed by state-appropriated
funds. Opinions expressed do not
reflect the official views of the uni-
versity. Use of trade names implies
no endorsement by the University
2005 University of Florida.
For permission to reprint any part
of this magazine, contact the Editor,
Explore magazine, Box 115500,
Gainesville, FL 32611-5500.
Phone: (352) 392-8229
Visit Explore on the World Wide
Joseph M. Kays
Patricia B. McGhee
Design and Illustration:
*^ A .
StorterChilds Printing, Gainesville
Member of the University Research
Summer 2005, Vol. 10, No.
Research at the University of Florida
I 0 Bowls of Liquid Light
UF researchers are seeking to understand and protect Florida's
springs, which are threatened by massive withdrawals from the
aquifer and pollution from nitrates and other substances.
I 6 Lakewatch Legacy
Decades of data on Florida's lakes open the door to insights -
and questions about their current and future health.
22 A New Tune
Years of research on nitrate pollution and agricultural solutions
to combat it all spell relief for the historic Suwannee River.
What Price Water?
Microbes And Plants Can
Clean Up Toxic Spills
Superfund sites are infamous for
their hazardous, stubborn chemical
wastes, but one cleanup solution may
be to put the right mix of plants and
microbes together in the soil, according
to a new University of Florida study.
The study examined the interaction
between two of the likeliest candidates
for cleanup duty the loblolly pine
and soil-dwelling, methane-eating bac-
The practice of planting chemically
resilient trees and plants in contami-
nated sites to absorb harmful chemicals
from the soil, known as phytoremedia-
tion, is highly appealing both to envi-
ronmental cleanup agencies and to the
communities near the hazardous sites.
Phytoremediation is still in its infancy
but has the potential to be relatively
safe, sustainable and efficient and
the trees are aesthetically pleasing as
Microbes in the soil also play a
key role. They help plants not only to
absorb nutrients through their roots
but also to soak up contaminants.
However, the interaction between
plants and microbes is not necessar-
ily symbiotic, according to the study,
which appeared in the January issue of
the Bulletin ofEnvironmental Contami-
nation and Toxicology.
"We're trying to see what the role
of the microbes is in the rhizosphere,
the soil region around the plant roots,"
said Adriana Pacheco, a graduate stu-
dent in UF's environmental engineer-
ing department and the lead author of
the paper. "It seems to be one of the
most important processes occurring."
Pacheco's research focused on
methanotrophs, bacteria that consume
methane in soils and in the process
can also consume and break down a
range of harmful organic compounds
that may be present, such as the car-
cinogenic polychlorinated biphenyls,
commonly known as PCBs, and tri-
chloroethylenes, or TCEs.
However, not all trees work equally
well with all kinds of microbes, and
knowing how the different plant spe-
cies affect the bacteria may be the
key to effective and efficient cleanup,
In her study, she focused on one
tree species, the loblolly pine, a prime
candidate for phytoremediation at a
number of Superfund sites, particularly
in the southeastern United States.
Loblolly pines are well known for
supporting thriving populations of bac-
teria near their roots, possibly because
of the piles of needles littering the
soil and releasing a pungent group of
chemicals called monoterpenes.
"These terpenes have been shown
to inhibit bacteria," Pacheco said. "But
methanotrophs can also be in really
high concentrations in the rhizosphere
of the pines, and they are degrading
TCEs. So one of the questions is, are
monoterpenes helping them in some
To answer this question, Pacheco
isolated several different species of
methanotrophic bacteria, fed them
methane and added monoterpenes
as well as TCEs, and then measured
the bacteria's response to the mono-
terpenes by observing how oxygen
levels in the samples changed over
time. She found that while some
species of the bacteria thrived when
the pine chemical was added, the
chemical appeared to be toxic to
others. That, she said, suggests
environmental engineers will need ,.
to choose both plants and microbes
carefully when planning phytoreme-
Scientists also want to address
what happens to the contaminants
after they've passed through the
"It's a very aesthetic treatment,"
said Angela Lindner, a UF professor
of environmental engineering and co-
author of the paper. "Trees and plants
are very resilient. They can accumu-
late the chemicals, and many times
they will also transform the chemicals
within the plant, and then the prod-
ucts as well as the chemical can volatil-
ize through the leaves. But we need to
know where the stuff is going."
For methanotrophic bacteria,
at least, the fate of the chemicals is
known. The bacteria produce an
enzyme that breaks down harmful
chlorinated compounds into harmless
carbon dioxide, oxygen and water.
Adriana Pacheco, firstname.lastname@example.org
4 Summer 2005
Students Build Smaller,
Smarter Heart Pump
A miniaturized heart pump
designed by a team of University of
Florida engineering students could
become a lifesaving alternative for
patients waiting in long lines for scarce
The UF team is creating a device
with a novel pumping technology that
makes it smaller and smarter than cur-
rently available ventricular assist devic-
es, which are too large to be implanted
in many patients. The pump's small
size also means it would be the first
such device in the United States that
could be used in children.
"Current (heart pumps) are really
large and complicated, so we're aim-
ing to build one that's smaller and
allows more types of applications," said
mechanical and aerospace engineer-
ing student Ella Kinberg, the project's
Ventricular assist devices, or VADs,
are connected to a patient's diseased
heart, internally or externally, to help
it pump blood. Although most VADs
are used to sustain a patient's life until
a donor heart becomes available, they
also can help patients recover from
trauma such as open heart surgery,
eliminating the need for a transplant.
VADs also are being developed to act
as long-term replacement hearts, a pro-
cess known as destination therapy.
The UF student team designed the
device as part of the College of Engi-
neering's yearlong Integrated Process
and Product Design, or IPPD, program,
a government- and corporate-sponsored
research and education program. The
team's goal was to design a smaller,
more efficient version of an innovative
prototype pump originally conceived
by UF biomedical engineering doctoral
student Mattias Stenberg, who acted as
a project adviser.
Stenberg designed the original
device in 1999 while working with UF
mechanical and engineering profes-
sor Roger Tran-Son-Tay. Stenberg
returned to UF in 2004 to develop and
test the prototype with Tran-Son-Tay
and UF College of Medicine assistant
professor Charles Klodell. Both Tran-
Son-Tay and Klodell were faculty
advisers on the IPPD project.
"The one thing that (this pump)
has that no other pump has is continu-
ous inflow with pulsating outflow,"
Klodell said. "It has a continuous
pre-filling chamber, something that
nobody else has come up with."
In a human heart, oxygen-rich
blood enters the left atrium from the
lungs and is pumped out to the body
through the left ventricle. The pump
prototype was modeled after this sys-
tem, using a dual-chamber design that
enables the pump to fill throughout
the pumping cycle. A push-plate valve
moves fluid into the main pumping
chamber, allowing the filling to transi-
tion easily and smoothly.
Standard displacement pumps fill
during the diastole phase of the pump-
ing cycle, when the heart is relaxed, but
not during the systole phase, when it
contracts. Consequently, displacement
pumps need to fill the same volume,
but in half the time, Stenberg said.
With a continuous inflow, the UF
pump is able to reduce the pressure on
the blood while injecting it into the
pump an important modification
because higher pumping pressure could
cause damage to the red blood cells,
thereby starving the body for oxygen,
The pulsating outflow allows for
greater control over fluid volume pass-
ing through the pump. The pump is
sensitive to changes in inflow pres-
sure as well, such as during times of
increased activity, so that if the pres-
sure increases, it starts to pump more
blood a self-regulating feature also
copied from the way a human heart
The design "offers the mechanical
reliability and the pulse-style flow of
traditional displacement pumps with
the potential for significant miniatur-
ization," Klodell said.
The size of the pump is restricted
by available space in the abdominal
cavity. Most adults can't receive a cur-
rently available VAD, which requires a
body surface area of 1.5 square meters,
Stenberg said. For pediatric use, that
size shrinks to 0.7 square meter.
Once the new pump has been thor-
oughly tested in the laboratory, the
next step will be to implant the pump
in a pig for live, in vivo testing. The
final step in the testing, human trials,
may begin within 18 to 24 months,
"Currently we do about 2,200 heart
transplants per year, but we have about
5,000 people on the donor waiting
list," he said.
Mattias Stenberg, email@example.com
"Out Of Africa" Theory
"Into Africa" rather than "Out
of Africa" could well be the better
description of how certain mammals
originated and spread across the planet,
according to a University of Florida
scientist, who has found the first evi-
dence for origins in North America of
a mammal thought to be endemic to
Long considered the cradle of many
mammal species, Africa no longer lives
up to that image with the discovery in
the Wyoming badlands of 54-million-
year-old skeletal remains of the first
elephant shrew, said Jonathan Bloch,
a UF paleontologist who described his
team's finding in the March 24 issue
of the journal Nature.
"Elephant shrews part of a
group that includes elephants, sea cows
and aardvarks are thought to be
endemic to Africa, yet we have found
evidence of their beginnings in North
America," Bloch said. "This research
has broad implications because it indi-
cates there may have been a great deal
more interchange in terms of how ani-
mals moved around the world as the
continents broke up than previously
The identification of the elephant
shrew, a small-bodied, hopping mam-
mal, is consistent with the observation
that other mammals, including pri-
mates, also moved around the world
during the course of their history,
"It is at least possible that primates,
like primitive elephant shrews, evolved
in North America and spread from
there into Europe, Asia and Africa,"
said Bloch, who works at the Florida
Museum of Natural History on the UF
The first modern mammals
appeared about 55 million years ago,
roughly 10 million years after the
mass extinction of the dinosaurs that
had dominated them. In this Eocene
period arose the first modern primates,
the first recognizable horses and many
other mammals, Bloch said.
"After the extinction of the
dinosaur. 6; million ear'
ago. thcre a an
explosion of diversity," he said. "Mam-
mals had a huge celebration with all
the big predators gone and they just
kind of took over. They went crazy,
filling all the open ecological niches
they couldn't have exploited while the
dinosaurs were still around."
About 55 million years ago, a dra-
matic short-term global warming event
took place. It lasted 100,000 years at
the most, but it brought about the
emergence of a huge assortment of new
creatures all over the globe, Bloch said.
With the warmer climates, the animals'
ranges expanded, he said.
As the once-giant land mass, or
supercontinent, known as Gondwana
separated into smaller continents,
land bridges temporarily formed that
allowed generations of animals to
migrate from one part of the world to
another, he said.
Once the continents disconnected,
animals were thought to have been
isolated, Bloch said. But the recent
Wyoming discovery suggests the
ancestor of certain mammals now liv-
ing in Africa, such as elephants and
primates, could have entered Africa
from elsewhere, he said.
Shawn Zack, the paper's senior
author and a graduate student at Johns
Hopkins University, found hind limb
and fore limb bones of an elephant
shrew, along with some teeth, in a
Wyoming quarry several years ago,
"It's incredibly important when we
come across a bone in association with
teeth because then it's like finding a
Rosetta stone," he said. "The next time
you find one of these bones you know
to whom it belongs."
Jonathan Bloch, firstname.lastname@example.org
6 Summer 2005
Ideas About Fossil
The old gray mare, she ain't what
she used to be, says a University of
Florida researcher whose findings
show that the evolution of horses had
more twists and turns than previously
According to conventional notions,
horses simply became bigger over time
and switched from being diminutive
shrub nibblers to the statuesque, grass-
eating masters of the open plains, said
Bruce MacFadden, a UF paleontolo-
gist whose research appeared in the
March 17 issue of the journal Science.
But the new horse sense is that the
equine mammals are adaptable critters
whose size, diet and range depended
on geography and climate, he said.
"The old ideas about how horses
evolved made for a fairly simple and
tidy story," said MacFadden, whose
1992 book "Fossil Horses" is consid-
ered the definitive work on the subject.
"But many of the concepts about horse
evolution that came into being during
the 20th century are now outmoded,
giving way to an understanding of
the fossil horse sequence that is much
Because horses have been around
a long time, learning about their evo-
lution provides unusual insight into
the patterns of evolution in general,
said MacFadden, who works at UF's
Florida Museum of Natural History.
"Horses are a very good example
because there is a long, continuous
fossil sequence of horses extending 55
million years in North America, pro-
viding the tangible evidence to trace
individual steps or changes in evolu-
tion over a prolonged period of time,"
Children often learn in social stud-
ies classes how the Spaniards brought
horses to the New World in the 1500s,
eventually producing vast herds of wild
horses on the prairies and helping to
create America's legendary cowboys,
MacFadden said. But the fossil record
shows horses actually originated in
North America at least 55 million
years ago and roamed the continent
before becoming extinct at the end of
the last Ice Age, about 10,000 years
ago, he said.
Scientists once universally thought
the more primitive horses, which lived
from about 55 million to 20 million
years ago, were primarily leaf-eating
browsers, only becoming grass eaters as
the prairie grasslands began to spread
rapidly across North America during
the Miocene Epoch about 20 million
years ago, MacFadden said.
The reality is not so clear-cut,
MacFadden said. Actually, during
times of transition, some groups of
horses became mixed feeders, eating
both grasses and leafy material, he
MacFadden analyzed the chemistry
of fossilized teeth to determine horse
diets. Animals incorporate into their
skeletons and teeth the carbon content
of the plants they eat, he said, and
grasses photosynthesize carbon differ-
ently than do leaves, shrubs or trees.
John Flynn, Frick Curator of fossil
mammals at the American Museum
of Natural History, said MacFadden's
findings are important because the
history of horses has been one of the
mainstays of evolutionary studies, biol-
ogy textbooks and museum exhibits
since the 1800s.
"Bruce MacFadden's Science 'Per-
spective' on horse evolution elegantly
summarizes the latest information on
their fossil record, and the knowledge
that continues to arise from a wide
variety of analyses of both new discov-
eries and existing fossils," Flynn said.
"And there's no one better than Dr.
MacFadden to provide this synthesis,
since Bruce has long been a world
leader in understanding horses, past
Just as the scientific knowledge
about whether horses were browsers or
grazers has changed, so have ideas about
the evolution of body size, he said.
The preconceived notion that the
horse was once as small as a dog but
progressively grew to its present stature
now can be proven to be incorrect,
About 20 million years ago during
the Miocene Epoch, horses diversi-
fied in size rather than just becoming
larger, MacFadden said. While some
grew larger, others became smaller or
remained the same size, he said.
Bruce MacFadden, email@example.com
Live Oral Bacteria Found
In Arterial Plaque
Gum disease has been linked to
hardening of the arteries for nearly a
decade, and scientists have long fin-
gered a gang of oral bacteria as the
obvious suspects behind many cases of
the vessel-clogging killer.
Now University of Florida research-
ers have cornered the bacterial ring-
leaders of gum disease inside human
artery-clogging plaque the first con-
crete evidence to place the pathogens
at the heart of the circulatory crime
scene. Their report appeared in the
March issue of Atherosclerosis, Throm-
bosis and Vascular Biology.
"Our finding is important because
it has proved there are live periodon-
tal bacteria in human atherosclerotic
tissue," said study investigator Ann
Progulske-Fox, a professor of oral biol-
ogy at the UF College of Dentistry.
"Now we can begin to understand how
these bacteria contribute to the disease
The oral bacteria UF researchers
found in the plaque, Porphyromonas
gingivalis and Actinobacillus actino-
mycetemcomitans, are two of the most
aggressive offenders in periodontal dis-
ease, the leading cause of adult tooth
loss. Because of the strong association
between periodontal and cardiovascu-
lar diseases, scientists have postulated
for years that oral pathogens contribute
to arterial damage that leads to heart
attack or stroke, which kills nearly a
million Americans a year.
Progulske-Fox's team took the
unusual approach of attempting to
grow bacteria from arterial plaque
directly on human artery cells. They
obtained a section of a diseased carotid
artery from a 74-year-old, partially
toothless male patient undergoing
surgery to remove an 80 percent block-
age at Shands at UF in Gainesville.
After removal, the sample was rinsed
and placed on ice, then rushed to
Progulske-Fox's nearby lab in a sealed,
Researchers pureed plaque from the
artery and incubated it. After 24 hours,
the cells were separated from the slurry
and subjected to a series of fluorescent
baths containing antibodies sensitive
to P. gingivalis and A. actinomycetem-
comitans bacteria. If any of the artery
cells were infected with the bacteria,.
fluorescent antibodies would light
Progulske-Fox and her team found
the endothelial cells were infected
with both P. gingivalis and A. actino-
mycetemcomitans, proving live bacteria
had been present in the atherosclerotic
Progulske-Fox plans to study ath-
erosclerotic tissue samples from 50 to
60 more patients to better understand
how bacteria infect arterial cells. She
suspects some strains of the bacteria
may be more successful in breaching
the barriers separating oral tissues from
"More study samples will show us
which strains are implicated in the dis-
ease process, so we can design simple
diagnostic technology that could be
used in a dental office to identify spe-
cific bacteria the patient is carrying
and whether that bacteria is known
to cause atherosclerotic disease," said
She envisions those diagnostic tests
would be the first step in the war
against periodontal and cardiovascu-
lar diseases, eventually leading to the
development of a vaccine that would
prevent oral bacteria from ever gaining
a stronghold in the mouth.
Ann Progulske-Fox, firstname.lastname@example.org
Detectors Used on
Shuttle's Fuel Tanks
The engineers who built the mas-
sive external fuel rank that will power
the shuttle Discovery into orbit used
sophisticated X-ray detectors developed
by UF researchers to reduce the chance
of a defect in the foam insulation cov-
ering the tank.
The detectors, first invented as a
new technology to find land mines,
can identify tiny gaps. or air-filled
\oids. in the insulating foam without
causing any damage. It is believed that
such a gap possibly located between
the foam and the rank's surface -
caused a suitcase-sized piece of foam to
break off during Columbia's liftoff in
lanuary 2003. The chunk struck the
edge of the shutde's left wing, seriously
damaging it and spurring the shuttle's
destruction during re-entry on Feb. 1.
"We can do the inspection of the
foam as it exists already sprayed onto
the tank. \'e don t have to cut into
it.' said Warren Ussery. team leader
for the return to flight nondestructive
evaluation team at Lockheed Martin's
8 Summer 2005
Nlichoud Assembly Facility in New
Orleans, where the shuttle's external
ranks are manufactured. "We're able
to find critical voids with that (the UF
UF nuclear engineering Professor
Ed Dugan and retired nuclear engi-
neering Professor Alan Jacobs began
experimenting with the modified
"backscarrer" X-ray detector several
years ago as part of research aimed at
engineering a more effective land mine
Conventional X-ray machines pro-
pel radiation through a target object
to radiographic film on the other
side. Different objects absorb X-rays
to differing extent, so some show up
more prominently on film than oth-
ers Backscatter X-ray machines vere
des eloped for circumstances when
it is impossible to place film behind
the objeCi ai~is the case with the
shuttle tank. Contrasting conventional
machines, they obtain images by cap-
turing the radiation scattered "back'
from the target.
Dugan said conventional backscar-
ter detectors select only the radiation
- which takes the form of photons
- that has had a single collision with
the target object. The detectors ignore
"multiple-collision" photons, which
may have hit the target several times,
because with conventional image pro-
cessing, they tend to cloud the image.
One of the unique ad antages of the
UF-built machine is that it draws use-
ful images from these multiple-colli-
sion photons, he said.
"There's a lot of good information
in multiple-collision photons. but
learning how to use it was not trivial,
Twin detectors pick up photons
from both single- and multiple-col-
lision photons, with a computer
merging the two using complicated
algorithms. In U.S. Army-sponsored
tests, the technology proved adept at
locating landmines, but the images
were equally striking because they
showed tiny empty spaces in the mines
"The photons would zip across the
voids and bounce back," Dugan said
"It allowed us to tell mines from tree
stumps and stones, because we had
high-intensity areas where the voids
Jacobs and Dugan realized this
capability made the detectors ideal
for identifying flaws and defects in
materials such as the carbon fiber used
in airplanes without having to rip the
material itself apart. The first tests of
the concept, done on airplane frame
members and small components,
proved promising. After the Columbia
disaster, word of the positive results led
to an inquiry from Lockheed Martin.
For preliminary resting purposes,
the aerospace giant provided the UF
researchers with sample chunks of fuel-
tank foam containing known flaws as
well as samples with unknown flaws.
Some of the foam pieces were melded
to the aluminum skin of the fuel tanks,
while others consisted solely of foam.
The UF detectors identified all signifi-
cant flaws both within the foam and
lying between the foam and the fuel
Ed Dug3n. edugan@ufl edu
I. u I
j~~~~ REERHR6EK UDRTN N
Renowned University of Florida naturalist Archie Carr called them "little
ecologicjewels" and cthe singular blessing of the rlorida landscape."
Environmentalist Marjorie Stoneman Douglas c.-illJ them "bowls
of liquid light," and iSth-century explorer william Bartram called them
"enchanting and amazing crystal fountains."
Geologically, Florida's 700 springs are windows into the
Floridan Aquifer 100,000 square miles of perme-
able limestone saturated with water like a giant sponge
that underlies all of Florida and parts of Georgia, South
Carolina and Alabama.
For eons, rainwater has trickled from the surface down to
the aquifer, only to reappear days, months or years later from
the springs, to form rivers like the Ichetucknee and the Sil-
ver, evaporate and fall again as rain in a never-ending cycle.
For much of history, human impact on the springs and
the aquifer has been minimal. Although archaeological evi-
dence indicates humans have lived around the springs and
along the rivers they feed for thousands of years, it is only
in the last century, as Florida's population has mushroomed,
that humans have begun to negatively impact the state's fresh
Beginning in the 1880s, Jacksonville, Fla. and Brunswick,
Ga. became the first municipalities to punch wells into the
Floridan Aquifer to provide drinking water for their growing
populations. Today, Floridians use more than 7 billion gal-
lons of water a day, more than 60 percent of it groundwater.
At the same time that more water is being withdrawn
from the aquifer, nitrates and other pollutants from septic
tanks, treatment plants and stormwater and agricultural run-
off are contaminating the surface water that replaces it.
The springs are suffering "death by a thousands wounds,"
says Jim Stevenson of the state's Springs Task Force and the
Ichetucknee Springs Basin Working Group
"Between 1950 and 1990, Florida's human population
more than quadrupled, and our population continues to
increase," a November 2000 report from the task force said.
"Since the 1970s, scientists have documented a decline in
water quality in most Florida springs, particularly in regard
to nutrients such as nitrate."
Over the past 30 years, typical nitrate levels in Florida
springs have risen from 0.02 milligrams per liter to 1.0 mil-
ligrams per liter, according to the report.
During a recent day-long tour of the Ichetucknee Springs
basin, Stevenson illustrated the many ways development is
impacting, and being impacted by, the springs.
He starts in Lake City at Alligator Lake, which regularly
flushes its water into a sinkhole that ultimately leads 12
Explore I I
miles south to Ichetucknee Springs. protection legislation and tools to
Lake City used to pump its treated sew- ,ectr help local governments implement it.
age into the lake. Now, the city sprays the 41gator Lake in Lae The model springs protection legis-
effluent over some 350 acres of hay field just a stone's throw lation that law students Matthew Brewer, Matt Clark and
from the Ichetucknee Trace, the historic path of the Christine Francescani, and interdisciplinary ecology doc-
Ichetucknee River, now mostly underground, toral student Jason Evans drafted at the behest of the Silver
As the tour follows the current and historic path of the Springs Basin Working Group required the state Department
river south, Stevenson points out gas sta- of Environmental Protection (DEP) in
tions almost on top of sinkholes feeding cooperation with the Florida Geological
the springs, and mobile homes being Survey to delineate springsheds and pri-
swallowed by sinkholes in an area I mary and secondary protection zones
that was once the riverbed. Canoeing for all first- and second-magnitude
down the Ichetucknee River from the springs. Flow from first-magnitude
headwaters, Stevenson then points h springs, the largest, exceeds 64 million
out the ecological implications of the gallons a day.
pollution. Mats of algae float past the mWde l Once this was completed, the law
canoes, algae covers the eelgrass that grows 1'" utrientspromote required local governments to review their com-
along the river bottom and water lettuce threatens to clog prehensive plans to ensure that they addressed any springs
some of the seven springs that feed the river, in their jurisdiction. The law also required DEP to establish
For Richard Hamann, an environmental law expert in the total maximum daily loads of nutrients for all impaired first-
UF College of Law's Center for Governmental Responsibil- and second-magnitude springs and adopt new criteria for
ity (CGR), it was a tour like this that opened his eyes to the determining impairment.
extent of the springs pollution problem. The model legislation ultimately evolved into the
"It wasn't until I saw the spravfields and the sinkholes that .. "Florida Springs Protection Act"
I realized hov con-prehenmi.c an',. prLngs pFuertiron li la- I rodu,:cd during the 2005 leg-
tion would hai t, r as Hamann. 1"i as .mostr irrplzc.ed ~. Islavite _iisi,n by state Sen.
by how far from the hieadv.arter ,ou could ha. e p. lluil-A, & :n Njncv' Acrcenziano of Dun-
impacting the ,prin-.. ll ri n and state Rep. Dwight
Last year, Hamanr, ad. i-ed tem [ ,iT stu- Snse! -'F Wellborn. The
dents from C(GR's (C,,n'en. an on (C1nc act ia .tripped of most of
in the developenr ent oi pring its requirements and then
River ... Floridians draw
~ billions ofgallons
\ of pure water daily
.from the Floridan
"D b, to the springs. The bil-
A%,"l -lions ofgallons theypour
backk as treated sewage,
r. t- waterr and agricul-
t.. ..! r ,, :ff cause dramatic
hi .e:'i: i. polluting nitrates.
stalled as the session expired in May, but Hamann says its
introduction was an important first step.
"We weren't looking to propose something
that was politically possible; we were
looking to do something that was
needed," Hamann says of the leg-
islation. "This kind of legislation
doesn't happen overnight, but the
fact that we set in motion serious
consideration of the problem and
potential solutions is an achievement."
"Getting sponsors and getting it
introduced was a big first step," adds Fay o
Baird, coordinator of the Silver Springs Basin Working
Group. "I was very impressed with the quality of the legisla-
tion we received from Richard Hamann and the students."
Margaret Carr, a UF landscape architecture associate pro-
fessor, says "this legislation is part of the building momen-
turn to tie land use to groundwater protection. What initially
seems like a radical idea eventually becomes possible."
Four years ago, Carr led a group of 17 urban and
regional planning and architecture stu-
dents who developed a land-use plan
to protect the water quality, water
quantity and native habitats of the
The final plan the team pre-
s,:. rented to Columbia County
S elected officials and administrators
o e i,, sought to balance population growth
ows, on the boro0 01 around Lake City, with the desire to
preserve the area's agrarian heritage and protect the
One of the keys to effective legislation and land-use plan-
ning to protect springs is understanding exactly how water
moves through the karst system. That's what UF geological
t IT WASN'T UNTIL I SAW THE
SPRAYFIELDS AND THE SINKHOLES
THAT I REALIZED HOW COMPRE-
HENSIVE ANY SPRINGS PROTECTION
LEGISLATION WOULD HAVE TO BE. I
WAS MOST IMPRESSED BY HOW FAR
FROM THE HEADWATERS YOU COULD
HAVE POLLUTION IMPACTING THE
- RICHARD HAMANN
Jim Stevenson and Richard Hamann at Ichetucknee Springs State Park.
sciences Associate Professor Jon Martin
is studying at one of the most unique
areas in Fli ,idjs springs system.
Unlike the karst geology of the
central continent that has pro-
duced places like Mammoth Cave
in Kentucky and Carlsbad Caverns in
New Mexico, most of Florida's caves are
So Martin is focus-
", ing his research on a
stretch of the Santa
Fe River that goes
more than six
Park in High
"O'Leno is a
Algae floats along the surface and covers the
eelgrass that grows along the river bottom.
because it has
mapped by cave
divers," says Mar-
tin, who is a member
of the Springs Task Force." e Ic '
"We can track water as it enters the damann snorkles t
system and as it comes out."
Martin and his colleagues, including geological
sciences doctoral student P. J. Moore, are using a variety of
mechanical and chemical techniques to track water in the
Santa Fe River from when it disappears beneath the surface
at a point called the river "sink" until it reemerges six miles
later at the river "rise."
"We monitor the chemical composition of the water
along the flow path," Martin say. "We also monitor the tem-
perature and measure the chemistry to see how it changes.
We're basically developing a natural chemical fingerprint for
Specifically, Martin's team is trying to understand how
14 Summer 2005
(Clockwise from left) Jon
Martin inserts a pump
into one of eight wells his
team has drilled around
O'Leno State Park. The
samples, clearly marked
by date and location, are
fixed with acid by doc-
toral student PJ. Moore
to prevent them from
spoiling before they can be
analyzed in Gainesville.
water moves between large conduits like sinkholes and springs
and the saturated limestone "matrix" that surrounds them.
"Water flows rapidly through the big conduits, but much
more slowly through the matr':," Martin
says. "We're trying to understand
how these two types of flows
Interaction between the
matrix and the conduits
has important implications
for human and ecological
health, Martin says.
"The water we drink
comes from the matrix
porosity. If a contaminant gets-. .:.
in the matrix, it could reside there
for a very long time and cleanup would be very difficult," he
says. "It will also slowly seep into the conduits and get out
into the springs, changing the ecology."
In addition to monitoring the water going through the
conduits, Martin's team has drilled eight 100-foot-deep wells
to get samples of the matrix water near the conduit.
"Using all of these techniques, we can plot what portion
of the water is from the matrix and what portion is from the
conduit," Martin says. "A lot of attention has been focused
on sinkholes and other large pathways
for contaminants to enter aquifers.
What is less commonly appreciated
is that the porous matrix provides an
additional, significant route for con-
taminants from the ground surface.
Consequently, results from this work
could provide the basis for a more real-
istic conceptual model of water flow in
the Floridan Aquifer." 0
Related Web sites:
Assistant Director,' Center for Governmental Responsibility
Associate Professor, Department of Geological Sciences
16 Summer 2005
L W tA
SS seafood dealer Jerry Jaillet doesn't live on a lake or
W. k have a background in lake science.
But as a volunteer for Florida Lakewatch, Florida's
largest lake monitoring program, Jaillet spends four hours
every month on Lake Ola in Orange County collecting
water samples, counting aquatic birds and gathering other
"You have a care for the lake, and this is just one way
to keep an eye on it," says Jaillet, 54, a Umatilla resident
who spent his boyhood on 446-acre Lake Ola, where his
parents had a nearby home.
Jaillet is one of about 1,800 volunteers who help
monitor more than 600 lakes in at least 40 of Florida's 67
counties through Lakewatch, a program founded at the
University of Florida Institute of Food and Agricultural
Sciences (IFAS) that turns 20 next year. His and others'
efforts are at the core of a steady stream of data routinely
tapped by lakefront homeowners associations and others
seeking to better understand and protect local lakes. Over
time, the volunteers' efforts have also resulted in
a massive lake water-quality database maintained
at Lakewatch's headquarters in UF's fisheries
and aquatic sciences department. Scientists and
Department of Environmental Protection (DEP)
TRAINED BY LAKEWATCH
STAFF IN SCIENTIFIC PROCEDURE,
VOLUNTEERS COLLECT SAMPLES
THAT THE SCIENTISTS USE TO ASSESS
ESSENTIAL LAKE INDICATORS.THESE
INCLUDE WATER CLARITY, AMOUNT
OF ALGAE, CONCENTRATIONS OF
PHOSPHORUS AND NITROGEN, AND
WATER COLOR AND SALINITY.
managers are among those who tap the database as they
make lake-management decisions.
The list of well-publicized threats c ir r..n -.- n Florida
lakes is long and menacing, but a top concern is nutrient
pollution from development tied to Florida's enormous pop-
ulation growth. As solid a resource as it is for scholarship and
management, Lakewatch founder and UF ..rh ri Professor
Dan Canfield says the Lakewatch database is also key to his
original and controversial view of this threat.
"The story that no one wants to hear," says Canfield, "is
that most Florida lakes are in great shape."
Florida is home to more than 7,700 lakes covering 6 per-
cent of its surface area, ranking it with Alaska and Minnesota
among the top five states with the most lakes. Its largest,
Okeechobee, spans 690 square miles, but 88 percent of its
lakes are a tiny fraction of that size, each covering fewer than
Most Florida lakes are shallow, usually fewer than 16 feet
deep, a result of their origins as sinkholes. Most are also rela-
ri cl-, oung, having first filled 6,000 to 8,000 years ago. A
r-i'..rrmcd as depressions in an ancient seabed or through
the flow of rivers and ocean currents. At least one, Baker
County's Ocean Pond, is thought to trace its origin to a
UF scientists have sought to keep track of the state's lake
conditions since at least the mid-1960s, but work on what
was then called the Florida Lakes Database ended in the
mid-1980s. Canfield, who earned his doctorate from Iowa
State University and began his career at UF in 1979, picked
up the slack in 1986, launching Florida Lakewatch after resi-
dents around a handful of North Florida lakes queried him
about their lakes' conditions.
Trained by Lakewatch staff in scientific procedure,
volunteers collect samples that the scientists use to assess
essential lake indicators. These include water clarity, "green-
ness" or amount of the algae-caused pigment chlorophyll,
concentrations of the nutrients phosphorus and nitrogen,
and in some cases water color and salinity. The volunteers
freeze the water they dip from their lakes and drop it off
at collection stations, including IFAS extension offices and
sheriff's offices. From there, a Lakewatch van carries the
- R P I ST TE OF FLORID LAKES ~ n s ~ u f~
A typical oligorrophic water body will have clear
water, few aquatic plants, few fish, not much wildlife
and a sandy bottom.
18 Summer 2005
A typical mesotrophicwaticr body will have-oderdyate .'
clear water and a moderate amount- of aqrtic pants.
samples to Gainesville for analysis. Over time, the numbers
add up to a comprehensive profile of each monitored lake,
a profile that gets updated annually.
One result: Homeowners and other interested parties
become better interpreters of their lakes' changes, Lakewatch
staff members say. That may lessen concern when something
seems abnormal, although the reverse also can be true.
"It gives them a cushion of comfort, an understanding
of how natural systems fluctuate," says Claude Brown, who
oversees Lakewatch's North Florida lakes as one of the pro-
gram's five regional coordinators. "Over the short term some-
thing can look pretty scary, but it may be in the expected
dynamics of a dynamic system."
At Lake Ola, for example, Jaillet is leaning on his Lake-
watch data and expertise to advise a homeowners association
on the best way to address a burgeoning problem with the
invasive weed hydrilla. The association could turn to her-
bicides or plant-eating grass carp but needs to be careful to
maintain some plants or algae will replace them, clouding
the predominantly clear lake.
Although there's certainly no mandate to do so, home-
owners have also used Lakewatch data to restrict develop-
ment and seek environmental protections, perhaps most
notably at Lake Disston in Flagler County. There, encour-
aged by former Lakewatch director Sandy Fisher, home-
owners relied on data they began collecting in 1992 to
demonstrate the lake's pristine quality, proof that helped
them win an Outstanding Florida Waters designation nearly
a decade later. Led by lakefront resident Ann Moore, they
also tapped the data to convince Flagler County commission-
ers to rebuff a developer who wanted to build 360 lakeside
homes and a golf course on a nearby creek.
Moore says Lakewatch empowers residents to act on their
lakes' behalf. Educated as a nurse and a full-time mother at
the time she started advocating for Lake Disston, her leader-
ship on the Outstanding Florida Waters designation led to
an invitation to become a member of the Board of Gover-
nors of the St. Johns Water Management District, a position
she occupies today.
"We found out later that no Outstanding Florida Water
designation had ever been accomplished by just a few house-
wives," she says.
Statewide, scientists and the Florida DEP turn to the
Lakewatch database for research and management.
"The database is more than simple water chemistry a
lot of times it gives you information about plants, fish and
bathymetric maps," says Mark Brenner, a UF associate pro-
fessor of geology and director of UF's Land Use and Envi-
ronmental Change Institute. "I think for other limnologists
it's a very handy source of information."
Scientists also turn to the Lakewatch numbers in debates
about Florida lakes' past and future. Canfield, for his part,
maintains that the numbers back up his contention that
Florida's nearly 16 million residents haven't had the terribly
degrading impact the public imagines.
"Florida lakes are not as bad as people have made them
out to be," he says.
s T \_. .
A ripical eutrophic water body will have either lots of
aquatic plants and.clear water orfew aquatic plant.. and
less clear water. In either case, it has the potential to sup-
port lots offish and wildlife.
A typical ipereutrophic water body will have very ilo6.
water clarity and the potential fr lots offish and. wild-
life. It may have an abundance ofaquatic plants.
Ir"r~"""""""""LL"~3L-C""~l -I ~I 'II '
It's not a message often spouted by academics in environ-
mental disciplines, but then Canfield breaks the ivory tower
stereotype. A registered Republican, he has a George W
Bush sticker on his pickup and allied with the late George
Kirkpatrick, the state senator who infuriated environmental-
ists with his staunch support of the Rodman dam.
A comprehensive assessment of the Lakewatch and other
data, he argues, shows that for at least the past two decades
most Florida lakes have held their ground or improved at
least as far as their trophicc status" is concerned. Trophic
status is a measure of nutrient enrichment, often seen as an
inevitable consequence of the septic tanks, wastewater treat-
ment plants and agriculture that accompanies growth.
The DEP uses chlorophyll levels to determine trophic
status: the greener the lake, the more productive it is. By
that measure, Canfield says, the Lakewatch data show most
lakes have remained stable, and those where increases have
occurred are almost inevitably lakes where managers have
aggressively attacked aquatic plant growth. That's important,
he says, because when aquatic plants die, chlorophyll-carry-
ing algae prosper.
Canfield and Lakewatch Assistant Director Mark Hoyer,
who shares his views, are among five authors of a 2000 paper
in the journal Lake and Reservoir Management that taps
Lakewatch and other data for 127 Florida lakes to make their
"Although the population of Florida has increased 116
percent over the last 27 years, expected increases in lake
concentrations of nutrients were not found," the paper says.
"Increased nutrient concentrations, or decreased water clarity,
that is often speculated to occur with population growth and
watershed development, have not been documented in this
sample of Florida lakes."
For Canfield and Hoyer, complaints about "pea soup"
water and muddy bottoms typically have less to do with
science than perception. Thanks in major part to phos-
phorus-rich soils under parts of the state and other natural
conditions, many Florida lakes are naturally both eutrophic
and very green, they say. But when newcomers arrive in
Florida especially those from states with deep, clear lakes
such as Maine they inevitably view Florida lakes as pol-
luted, they say.
People "think that every lake should be 'what I think a
lake is' and whatever they grew up with is what they think
about," Hoyer says. "Down in Polk County, the lakes are
green, and that's all they're ever going to be."
Lake lovers' judgments of lakes as "healthy" and
20 Summer 2005
"BY SAYING THAT THERE
HAVE BEEN NO CHANGES,
IT'S KIND OF APOLOGIZING
FOR THE HUMAN DEVELOP-
MENT THAT HAS OCCURRED,
THE MINING AND THE AGRI-
CULTURE. WHY NOT JUST
ACKNOWLEDGE THAT WE
DO HAVE A FOOTPRINT ON
THE LANDSCAPE AND THE
strata of meters-
long samples cored
from lake beds to
the lakes' historic
- MARK BRENNER
"unhealthy" are also colored by what they want to get out of
their lakes, Hoyer and Canfield maintain. Swimmers prefer
clear lakes with sandy bottoms, conditions which usually
indicate low or moderate nutrient levels. Anglers and bird
lovers, by contrast, may prefer greener lakes whose nutrient-
enhanced productivity can result in higher bird and sport
"Good and bad is in the eye of the beholder," Canfield
Other scientists agree that perception and personal bias is
a major, underappreciated issue when it comes to lake man-
agement. But many argue that the issue of human-caused
nutrient enrichment is far from settled. Brenner, the UF
geologist, says the Lakewatch data show little evidence of
nutrient spikes because it so recent. A paleolimnologist who
studies lake history by analyzing layers of recent and ancient
sediment, he says his work on lakes around Lakeland, for
example, does indicate a trend of nutrient enrichment.
A century and a half ago, when few if any people lived
nearby, Lakes Hollingsworth and Parker were "mesotrophic"
or mildly eutrophic, his research shows. Today, they're highly
"I feel like there are some changes that are happening,"
Brenner says. "By saying that there have been no changes,
it's kind of apologizing for the human development that
has occurred, the mining and the agriculture. Why not just
acknowledge that we do have a footprint on the landscape
and the waters?"
The poster child for human degradation of Florida
lakes is Orange County's Lake Apopka. Renowned early
this century for its outstanding bass fishing, Apopka's
extensive aquatic plants began dying off in the late 1940s
and were replaced by massive algae blooms. Sport fishing
fell off precipitously.
Many blame the lake's decline and current "hypereutrophic"
status on human causes, including phosphorous runoff from
adjacent farms and treated wastewater discharges from shoreline
communities through the 1970s. The state, which has embraced
these views, now operates a multi-million-dollar Apopka restora-
Canfield takes a skeptical view of the efforts, arguing that
the initial cause ofApopka's troubles was hurricane-gener-
ated waves that stirred up the lake's muddy bottom, cloud-
ing the water, preventing light from reaching the plants and
killing them. He and Roger Bachmann, a visiting professor
in UF's fisheries department, maintain Apopka's continued
eutrophication problems are less related to phosphorous
discharge than to a layer of fluid mud on the lake's bottom
that keeps the water turbid and makes it difficult for plants
to get established.
Whatever their position on Apopka, everyone acknowl-
edges that nutrient enrichment is not the only concern about
Florida lakes. Others include sedimentation, or filling-in of
lakes, contamination from mercury and pesticides and the
thorny issue of maintaining lake levels against conflicting
priorities like flood control and groundwater pumping.
For Canfield, it's essential to debate the causes and solu-
tions to these and other potential issues.
"Science is an area where we're supposed to have conflict,"
he says. "We're supposed to have hypotheses and debate
them out." 0
Related Web sites:
Professor, Department of Fisheries and Aquatic Sciences
Associate Professor, Department of Geological Sciences
MMORTALIZED IN SONG AND VERSE, THE
SUWANNEE RIVER HAS LONG BEEN KNOWN
FOR ITS PRISTINE WATERS, SO WHEN TESTS
INDICATED RISING NITRATE LEVELS AND THE
ENVIRONMENTAL PROBLEMS THAT ACCOMPANY
THEM, SCIENTISTS AND CITIZENS THROUGH
NORTH FLORIDA WERE SPURRED TO ACTION.
"The federal safety standard for nitrate-nitrogen in drink-
ing water is 10 parts per million, but in some areas we were
finding levels in the 20-to 30-parts-per-million range," says
David Hornsby, a water resources scientist with the Suwan-
nee River Water Management District in Live Oak. "Rising
nitrate concentrations in the river, springs and groundwater
have become a regional phenomenon in the past few years."
In addition to compromising drinking water, high nitrate
concentrations can degrade water quality in rivers and
springs, causing algae blooms that consume oxygen needed
by fish and other aquatic animals.
In 1999, concerns about nitrates prompted representatives
from agriculture, state and federal agencies, local govern-
ments and related associations to initiate the Suwannee River
Basin Nutrient Management Working Group, now known as
the Suwannee River Partnership.
The partnership which includes the University of
Florida's Institute of Food and Agricultural Sciences, or
IFAS, and 52 other members works to develop and pro-
mote strategies for monitoring and managing human and
animal waste and fertilizer in the basin.
Darrell Smith, partnership coordinator with the Florida
Department of Agriculture and Consumer Services, says the
main goal is to work with landowners and interested groups
to help protect the water resources of the Suwannee River
Basin through voluntary, incentive-based programs. Results
from water-quality monitoring and best management prac-
tices (BMP) programs are being made available to all produc-
ers and citizens.
"The partnership is focusing on finding the most eco-
nomical and technologically feasible management practices
Professors Don Graetz, left, and Wendy Graham
measure the water table through a monitoring well at
Suwannee Farms near O'Brien.
available to help farmers and other land users satisfy the
regulatory requirements for protecting public health and the
environment," Smith says. "Through an education and out-
reach program led by the UF extension service, the partner-
ship will increase public awareness of the issues, encouraging
citizen and community participation to find solutions."
The Middle Suwannee River Basin, which includes Lafay-
ette and Suwannee counties, has hundreds of residential and
commercial septic systems in rural areas, about 200 row crop
and vegetable farms, 40 dairies with more than 25,000 ani-
mals and 130 poultry operations with more than 38 million
birds. Suwannee County is the leading poultry production
area in the state.
Since its inception, the partnership has expanded beyond
the Middle Suwannee Basin and now includes all 13 coun-
ties in the Suwannee River Water Management District. In
addition to working with traditional agricultural producers,
the partnership is developing programs with the forestry
industry, aquaculture producers and other businesses and
homeowners to strengthen the watershed initiative.
"All of these activities have the potential to adversely
affect water quality in the basin," says Don Graetz, a profes-
sor in UF's soil and water science department. "At this time,
the public perception points to animal waste and fertilizer as
the most likely causes.
"Surface and groundwaters interact in most of the basin
due to the region's active hydrology and porous soils. The
mobility of nitrates, regardless of the source, makes it criti-
cal that we carefully evaluate where and how they enter the
aquifer," he says.
Graetz, an environmental chemist who leads the UF
research and education effort for the partnership, says many
state and federal agencies as well as agricultural producers
and associations are working toward the common goal of
controlling nitrates. A six-year, $2.5 million grant from DEP
and the federal Environmental Protection Agency supports
the UF work.
"The agricultural community, which is key to the area's
economy and green space, is just as concerned about pro-
tecting water quality as anyone else, and we're all working
together without finger-pointing or blame," he says.
Graetz and others in the partnership are cooperating with
15 producers in the basin to monitor groundwater quality
and evaluate the effectiveness of various BMPs. The program
began with three farms: Barnes Poultry Farm in Live Oak,
24 Summer 2005
Byrd Dairy Farm in Mayo and Suwannee Farms in 0 Brlen
which produces row crops and vegetables under more than
40 center-pivot irrigation systems on 5,000 acres. The
partnership has installed monitoring wells ac e e n
more dairies and five more poultry operation;
as part of the BMP project.
Kenneth Hall, manager of Suwannee
Farms, says the project provides a unique
opportunity to observe nitrate move-
ment through the soil in relation to crop
development and irrigation or rainfall.
"If we can do a better job of maxi-
mizing nutrient and water efficiency
while maintaining economic sustainability,
we certainly want to be among the first to
do so," he says.
George Hochmuth director of UF's North
Florida Research and Education Center in Li'. Oak
who is developing BMPs for Suwannee Farri. 4 a\s co' or-
siderable progress" has been made in adoptirn nrc'. produc-
"Improvements in the timing and placement of
nitrogen fertilizer have allowed farmers to reduce the total
amount of nitrogen applied and still achieve high-quality
crop yields," he says. "The key to nitrate management is irri-
gation management we are finding that newer and more
efficient irrigation nozzles are important for better nitrate
Wendy Graham, chair of UF's agricultural and biological
engineering department, is monitoring soil and groundwa-
ter quality and water movement, as well as crop nutrient
status and crop yields at the vegetable farms. Graham's team
employs data they have been gathering since 1999 to develop
computer models for predicting the impact of various nutri-
ent and water management practices on groundwater quality
and crop yield under different soil, weather and cropping
"We have a weather station and a network of monitor-
ing wells under one of the large, center-pivot irrigation
systems," she says. "Through this monitoring we have been
able to pinpoint the types of weather conditions and crop
management practices that result in nitrate leaching. This
information has allowed us to make recommendati,-n, ab:,ur
Al.:il\.q., f R'io.t i'lo R.w _f'!. l'' !Hiu p r-,','. .and
./orii., ,e' ,,w/.'i.S r:it l. :me 5.m,'"/ez eo.a;7 .tnc
,"e'i-tiP- ot ,rr-z:::, -),.>yY'a ar S, 'a'ie
F.'irf near O'Brio:.
practices that will
reduce nitrate loading
Graham said the
research has demon-
strated, on a com-
mercial scale, a suite
of improved practices
that reduce loads to
maintaining acceptable crop yields.
"But," she says, "demonstrating
that these practices, if implemented
throughout the Suwannee Basin, will
meet existing and future water-quality
standards is a challenge that requires
further research and development."
Rao Mylavarapu, an assistant profes-
sor and nutrient management specialist
in the soil and water science department, is
helping to develop nutrient management plans
that account for all nutrients applied to the crops at
the three demonstration farms in the partnership.
"We need to develop new cropping systems based upon
the exact nutrient needs of plants, which will minimize
nutrient losses to the environment," Mylavarapu says.
"The efficiency of nutrient utilization by crops can be
improved b-,- fine -tuning c:icting Fertili'ition prcticc.
d-crbbv reducing ntluier-[ lca-ing h'LUh he rd mo
groundwater. New BMPs that combine nutrient and water
management, particularly application rates and timing,
will hopefully optimize cultural practices in the Suwannee
Nutrient management plans, which incorporate various
BMPs, for Byrd Dairy Farm and Barnes Poultry Farm were
developed by another partnership member, the U.S. Depart-
ment of Agriculture's Natural Resource Conservation Service.
Conservation management practices for dairy and poultry
farms include application of animal waste on pastures and
Hochmuth says researchers at IFAS Livestock Waste Test-
ing Lab in Live Oak are working with the partnership to
provide precise analysis of nutrients in manures at the animal
farms. The UF lab is funded by partnership members.
"This gives producers a better idea of what nutrients are
being applied to crops and fields," he says. "Researchers at
the center are also developing other BMPs for crops in the
Suwannee River Basin area, including vegetables and
hay crops." Q
Professor, Department of Soil and Water Science
(352) 392-1803, Ext. 318
Professor and Chair, Department of Agricultural
and Biological Engineering
(352) 392-1864, Ext. 120
The Suwannee River is one of the nation's most
famous waterways. Now a team of nearly 100 researchers
from the University of Florida and a host of other univer-r
sides and government agencies hope to make it'on i p ,.
the most studied, as well.
Just as astronomers '
employ telescopes to better
understand outer space, earth Water lanag(
scientists hope to gather -
unprecedented amounts- ofi*
data about indivdlua iv ye : i
watersheds in an effort tof-
better understand the .atia
entLre hyd -ip system. 4
The NationalB Sience ;
both surface _e.It
issue a request for pro-ps
within the next year to fun_-iS- I
up to 10 National Hydrologic
Observatories at up to $25 N
million each forfive years.-
About two dozen groups_.. e ..-
around the'country are vying
to have their project selected
by NSF, including the Suwan- .- '
nee River team. si- ingle atrshe(
"The Suwannee is ideal for an observatory for both: f groundwater, .,
pure scientific reasons as well as practical envirori'mebi ~ TI;Hydr
applications," says UF geological sciences Assocaiate PFrfes- n nat.d through a
Ssor Jon Martin."Our proposal will focus on-the'i-pac ft ." arou e cou
humans on the watershed how .they have altered' itTand -' tis frIe Adv
how-much. further alteration it can handle.: HSI :
The researchers cite four major characteristics .f the 'l.d-idition-tc
.Suwianneeg River watershed that make it an ideal chbice to idual ~i ers~
':ahydro1ogic observatory. -.. ; ,.. ...data'between,
.Te-hiversdone.of few,,major=rivers in theU ited -!.- ... .-;-- Ev al
l ate by ams:r t1ertrL i
bra-- &l r'l^.-' -a "'-''. -"
ct t lin
ct, Ilit lin
2 upper Tiv
!r; the midi
dat bvt U f
-, ts _-0
What Price Water?
Sanford V. Berg
Distinguished Service Professor ofEconomics,
Director of Water Studies, Public Utility
This issue of Explore underscores
the University of Florida's
leadership role in research on water
issues that are so vital to our state.
a wide range
l standing of
rivers and estuaries.
One of those disciplines is eco-
nomics. UF's Public Utility Research
Center, or PURC, has devoted more
than 30 years to studying infrastruc-
ture policy in Florida and around
the world. PURC contributes to the
policy conversation through events
like last spring's statewide conference,
"How Should Florida's Water Supply
be Managed in Response to Growth?"
That event, co-sponsored by PURC
and UF's Askew Institute, brought
together policymakers and opinion
leaders from throughout the state to
discuss water management.
During that conference, several par-
ticipants and I emphasized that water
is not free, it has real costs. Economics
insists that we understand what we
are giving up when we make choices,
whether it's watering our lawns or
filling our swimming pools. Like all
scarce resources, use today takes away
from availability tomorrow, and use
"Economics insists that we
understand what we are
giving up when we make
choices, whether it's
watering our lawns or filling
our swimming pools."
by one sector diminishes availability to
another. Of course, valuing the contri-
bution of water is difficult. Wetlands
and estuaries contribute to the health
of the ecosystems, impacting biodiver-
sity and sustainability. Rivers, lakes and
springs provide all of us recreational
Economists in the UF College of
Business and in the Institute of Food
and Agricultural Sciences rely on
data from colleagues in hydrology,
demography, geography and other dis-
ciplines to develop models that provide
frameworks for capturing complexity,
understanding patterns and predicting
Sophisticated modeling is essential
if we are to establish solid, science-
based policy. Science can tell us past
trends, establish baselines and facilitate
the analysis of alternative scenarios.
Engineers look to technology for
solutions to water scarcity problems.
Hydrologists seek a greater understand-
ing of the impacts of water usage and
wetlands on water levels and flows
within watersheds. Environmental sci-
entists address ecosystem sustainability.
Planners deal with land use, popu-
lation growth projections and zoning
issues. Political scientists focus on
issues of power, legitimacy, social cohe-
sion and the roles of different stake-
holder groups. Legal scholars empha-
size procedural fairness and how due
process and transparency contribute to
the legitimacy of outcomes.
Despite the contributions from all
of these disciplines, our models are still
28 Summer 2005
Comparing Water Prices
(per cubic meter)
United Kingdom $1.18
United States $0.51
Source: United Nations, 2001
incomplete. It's said that all models hov
are wrong, but some models are use- for
ful. Water policy decisions are always
made on the basis of incomplete infor- trai
nation. We strive to develop models and
whose accuracy makes them useful to thr
decision makers. Ultimately, our policy mo.
decisions will reflect our values regard- and
ing water stewardship, hav
Economists understand the impor- Inte
tance of sending people price signals Util
that provide them with incentives to wee
conserve. From this perspective, water tim
is a commodity with values in alterna- role
tive uses, including future consump- rece
tion and environmental restoration. Awa
Experiences in other countries can 200
help us understand the impacts ofdif- part
ferent policies on water systems. Recent are
research at PURC has focused on evalu- regi
eating the performance of water utilities reac
in a number of countries, including the Car
United Kingdom, Uganda, Brazil and coui
Peru. These studies yield insights into Thr
v incentives can improve outcomes to water management affect sector per-
In addition, PURC has provided
ning to regulatory policymakers
Infrastructure executives from
oughout the world. Since 1997,
re than 1,400 utility regulators
managers from 126 countries
e attended the PURC/World Bank
national Training Program on
ity Regulation and Strategy, a two-
k course PURC has delivered 18
es. In recognition of its important
in international training, PURC
ived the World Bank President's
ird for Excellence in December
2 for "outstanding support and
nership." The training programs
supplemented by in-country and
onal PURC courses that have
hed all of Latin America and the
ibbean, Australia, South Africa and
entries in Europe and the Far East.
ough this dialogue, we can learn
from others about inno-
vative approaches to the
efficient management of
water resources and the
delivery of water services
to meet diverse needs.
Water problems are
complex: they are man-
aged, not solved. We
have much to learn about
.:' how different approaches
formance. Many perspectives are neces-
sary for developing and implementing
sound public policy.
UF recently formed a Water
Institute to bring together its consid-
erable expertise about water issues,
improving our understanding of aquat-
ic systems and contributing to more
effective water quality and quantity
policies. In the future, we anticipate
even more interdisciplinary research
through the institute.
We Floridians have a responsibil-
ity to leave future generations with
a legacy, not a disaster. The Florida
Legislature took a significant step
in that direction this spring when it
passed comprehensive water-quality
legislation that provides $100 mil-
lion a year to the state Department of
Environmental Protection to establish
and track maximum daily loads of
nitrates and other pollutants the state's
water bodies can handle. Much of the
science behind establishing those loads
has been and continues to be devel-
oped at UF
The university's impact on water
policy around the world illustrates the
kind of contributions that can be made
when multiple disciplines are brought
together to address major policy issues
like the management of water, a scarce
natural resource critical to our lives.
Taps Waste Heat From Power Plants
University of Florida researchers
have developed a desalination
technology that taps waste heat from
electrical power plants as its primary
source of energy, an advance that could
significantly reduce the cost of desali-
nation in some parts of the world.
"In the future, we have to go to
desalination because the freshwater
supply at the moment can just barely
meet the demands of our growing
population," says James Klausner, a
UF professor of mechanical and aero-
space engineering, whose research was
funded by a $200,000 grant from the
U.S. Department of Energy.
"We think this technology could
run off excess heat from utility plants
and produce millions of gallons each
day," said Klausner, lead author of an
'- article on the system that appeared in
MEN the December issue of the Journal of
aMm H Energy Resources Technology. He co-
MI invented the technology with fellow
UF mechanical engineering Professor
More than 7,500 desalination plants
operate worldwide, with two-thirds of
them in the Middle East, where there
often is no other alternative for fresh
water, Klausner said. The technology
Sis less common in North America,
where residents get less than 1 percent
of their water from desalination plants
James Klausner, a UFprofessor of mechanical and from plants located mostly in Florida
aerospace engineering, co-authored the desalination and the Caribbean.
technology that taps water heat from electrical power The need for desalination is likely
plants as its primary source of energy. to grow, however, as the population
increases and residents consume more
fresh water. In Florida, for example,
desalination has been touted as one
solution for metropolitan areas where
30 Summer 2005
freshwater resources are becoming ever
Most commercial desalination
plants now use either distillation
or reverse osmosis, Klausner said.
Distillation involves boiling and evapo-
rating salt water and then condensing
the vapor to produce freshwater. In
reverse osmosis, high-pressure pumps
force salt water through fine filters that
trap and remove waterborne salts and
Boiling the vast amounts of water
needed for the distillation process
requires large amounts of energy.
Reverse osmosis uses less energy but
has other problems, including mineral
buildup clogging the filters. That's the
main technical issue plaguing the larg-
est desalination plant in the United
States, Tampa Bay Water's $108 mil-
lion plant in Apollo Beach. Although
it was supposed to produce 25 million
gallons of freshwater each day, the
plant, beset by technical and financial
problems since opening in 1999, cur-
rently is shut down.
Employing a major modification to
distillation, Klausner's technology relies
on a physical process known as mass
diffusion to evaporate salt water.
Pumps spray salt water warmed as
a by-product of power plant cooling
processes into the top of a diffusion
tower a column packed with a
polyethylene matrix that creates a large
surface area for the water to flow across
as it falls. Other pumps at the bottom
of the tower blow warm, dry air up
the column. As the trickling salt water
meets the warm dry air, it evaporates.
Blowers push the now-saturated air
into a condenser, the first stage in a
process that forces the moisture to con-
dense as freshwater.
By tapping warmed water plants
have used to cool their machines to
heat the salt water intended for desali-
nation, utilities can turn a waste prod-
uct into a useful one.
Klausner has successfully tested
a small experimental prototype in
his lab, producing about 500 gallons
of freshwater daily. His calculations
show that a larger version, tapping the
waste coolant water from a typically
sized 100-megawatt power plant, has
the potential to produce 1.5 million
gallons daily. The cost is projected at
$2.50 per 1,000 gallons, compared
with $10 per thousand gallons for con-
ventional distillation and $3 per thou-
sand gallons for reverse osmosis.
To be cost effective, the desalination
equipment would have to extract as
much heat as possible from the coolant
water, so it would need to be incorpo-
rated into the plant's design, he said.
Also, a full-scale version of the mecha-
nism would require a football field-
sized plot of land, likely to be expen-
sive in coastal areas where power plants
are located, Klausner said. Presumably
a utility would sell the freshwater it
produces, recouping and then profiting
from its investment, he said.
Klausner said a miniature version
of the full-scale system could be run
using solar or other forms of heat,
which might be useful for small towns
The university has applied for a
patent on the technology and is seek-
ing a corporate partner to bring it to
the commercial market.
Professor, Department of Mechanical
and Aerospace Engineering
Courtesy of ampsa Bay Water andJeff Young l'stograpvy
Desalination processing membranes at
Tampa Bay Water plant.
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