Posted by Jane Clark for Peggy Murdock.
These notes are from the Pew Oceans Commission Nutrient Hearing Monday
morning, December 10.
The Pew Oceans Commission is comprised of 18 people from different
disciplines, some professional fishermen, some scientists, whose purpose is
to gather information and make reports to influence congressional decisions.
From There is one Midwestern member, a Kansas farmer who is president of a
sportfishing association. Four were present at this hearing.
The first speaker was Nancy N. Rabelias, Ph.D. of Louisiana Universities
whose area of expertise is the interaction of rivers and oceans.
A 1999 survey concluded that more than 66% of waters were eutrophic. This
is a worldwide problem. There are new areas of hypoxia and the size of
these areas is growing. The nutrients fueling this are nitrogen,
phosphorus, and silicon, which is necessary for the growth of diatoms.
41% of the land area of the U.S. drains into the Mississippi. The hypoxic
area extends from the Mississippi River Delta to the border of Texas and
sometimes into Texas. This starts in the spring and reaches its peak in the
summer. In the winter the waters are mixed and hypoxia disappears.
The amount of water and the nutrients in the water clearly affect this
phenomenon. In drought years the hypoxic area shrinks. It is clear that
the amount of nitrogen and also phosphorus is directly related to the size
of the dead zone.
Although most fish migrate out to sea, hypoxia causes fishkills.
Phytoplankton blooms and sediment reduce light, preventing the growth of
eelgrass and brown algae. Crabs and worms, which cannot migrate, die, thus
reducing the ability of the area to sustain life even when hypoxia is
absent.
There are also problems with juvenile shrimp migration, and the catch of
brown shrimp is directly related to increased water and nutrients coming
into the Gulf.
Dr. Rabelais' group began studying the Gulf in 1985. In order to get
historical data for the area they took sediment cores. These studies show
that the most dramatic change began in 1950 when the nitrogen concentrations
in the river increased.
A Gulf action plan with the acronym GOALS was presented to President Clinton
and is being studied by Christine Whitman during this administration as
well.
A lot of areas around the world and in the U.S. have developed nutrient
management plans. In some places point sources air deposition and ag runoff
indicate where you should implement your solution.
The next speaker was Dennis Keeney Ph.D., Professor Emeritus of Iowa State
University and Senior Fellow at the Institute for Agriculture and Trade
Policy in Minnesota. His subject was Nitrate in Streams Related to Land Use
and Land Management
He said there are a lot of escape mechanisms in the nitrogen cycle, which
make it hard to make large-scale predictions. Data gathered in two periods,
1945-51 and 1978-98, show there has been a tremendous increase in the amount
of nitrate in streams in the last 30-50 years.
There is a direct correlation between the amount of land planted in rowcrops
and the nitrate in streams. As the acreage planted in rowcrops increases,
so does the nitrate in streams.
Adding land drainage to the system increases production. High fertilizer
use is encouraged and grain is being produced for markets that do not exist.
Farm and trade policies encourage grain production and the freedom to farm
act has made the situation worse.
In order to lower nitrogen output you have to manage the nitrogen, time
nitrogen applications, match the soil nitrogen and account for crop needs,
tighten manure management rules, create sinks in the landscape, such as
wetlands, riparian zones, grasslands. Plant less rowcrops.
Healthy landscapes have ecological, economic and social benefits. We need
more grasslands, wetlands and forests. We should emphasize perennial energy
crops, carbon sequestration crops. We need more farmers on the land.
The solutions will involve landscape scale changes, different cropping
patterns, a 10-20% decline in rowcrops. Universities should be working to
devise different cropping patters rather than on finding out how to grow
more of the same crops.
The third speaker was Donald Goolsby, USGS, retired. His topic was Nitrogen
Flux and Sources in the Mississippi River Basin.
His study shows how nitrogen loads have changed over the last century and
what human activities have contributed to that. 80% of the land in southern
Minnesota, Iowa, Illinois, Indiana, and Ohio are devoted to rowcrops. This
land has high water tables high and has to be lowered by tile drainage which
skims off the top of the water table, taking the poorest water and draining
it off into stream where it runs to the Mississippi River and the Gulf.
Nitrate is the predominant form of nitrogen in the system. Without tile
drainage it would take months and years for this water to drain into the
Gulf.
Data collected in 1905-7 and 1980-96 studies show that nitrate levels have
increased in small rivers and more than doubled in the large rivers closer
to the Gulf. Since Most of the increase in loading occurred between 1960 and
1980. Since 1980 the mean concentration has leveled out but there is
variability driven by precipitation, the more precipitation, the higher the
concentration.
Before 1970 there was no variability linked to streamflow. They postulate
that this means nitrate builds up in the soil and is flushed out.
Where agriculture and drainage are most intensive the nitrate is highest.
Nitrate levels are directly related to the application of fertilizer.
Fertilizer and soil are responsible for 50% of the nitrate in our waters,
manure 15%, municipal discharges 11%, atmospheric deposition and unmeasured
inputs 24%. Legumes are not related to nitrate levels in waterways.
An article in Nature November 8 there is a University of Illinois study
that shows a relatively small decrease in nitrogen inputs to the basin can
result in a decrease of the load that goes to the Gulf. A 12% reduction in
fertilizer would means a 33% reduction in output. This is a fairly
significant reduction and has little or minimal effect on crop yields
The fourth speaker was William J. Mitsch, Ph.D, distinguished professor of
Natural Resources and Environmental Science, Director of the Olentangy River
Wetland Research Park at Ohio State University.
Dr. Mitsch reiterated much of what his colleagues had already said; the
highest levels of pollutants come from the highest levels of drainage,
reducing the nitrogen loading to the Gulf will involve onsite controls
including changing crop systems ,control of nitrogen fertilizer rates,
manure spreading, application training and more. Offsite controls of non
point agricultural drainage, municipal discharges, and more.
Runoff from home fertilizer accounts for a much lower percentage than other
sources, only 2-9%.
Ecosystem wetlands do reduce the load that is eventually passed into the
rivers. Well developed forests are also valuable for taking up nitrates.
There are three things to do: implement better fertilizer management,
develop 5 million acres of wetlands, and 19 million acres of riparian
ecosystems. Doing this would result in a 20-40% reduction in the nitrate
going into the Gulf.
A minimum of 4%of midwest should be soggy and wet. The value of this to the
midwest would be reduced nitrates in drinking water and reduction of other
pollutants, wetland habitat restoration, river restoration and flood
control.
A gain of 10million acres of wetlands should be achieved by the year 2010,
largely through reconverting crop and pastureland and modifying or removing
existing water control structures. 400,000 miles of rivers should be
restored. If three percent of the Mississippi River basin and 12 million
acres of the upper Mississippi were restored to wetlands and backwaters it
would provide flood control. There is already a dialog with the Army Crops
of Engineers about restoration.
A five year 27 million dollar study of this area is being done.
His vision is for a restoration on the scale of the Everglades restoration
being done in Florida. This restoration would involve 40% of the lower 48
states. It would require restoration in 23 states at a cost of 27 million
dollars.
Questions were then asked the speakers by members of the Pew Commission.
The first was about impediments to restoration.
The first person to answer was Dr. Rabelias
A 30% reduction in nitrates leaching into the water can be achieved with a
12% reduction in fertilizer use.
An economic collapse in the watershed of the Black Sea reduced fertilizer
application by 50%. This reduced the eutrophic area almost completely.
Impediments to reducing the system are social and institutional. There is a
long term history of increasing the use of nutrients and the mobilization of
nutrients in the system. Excesses could be reduced.
The social issue can be addressed by informing and educating people who will
then be willing to make a change.
The second person to answer was a man who stated that reducing nitrate
loading especially in May and June will reduce nitrate runoff. Education is
key in getting people to realize that there is excess in the system so that
they will be motivated to reduce the nitrate being put into the sysgtem.
The next to answer was Dennis Keeney. The Leopold Center concentrated at one
time on nitrate in groundwater. They cut use 20-30% and at the same time,
use was increased in Illinois. Fertilizer dealers and extension were
involved in the campaign and yields increased during this time. Since then
things have gone backwards.
When you have warmer falls and wetter springs farmers have to replace the
nitrogen that has been used and washed off of fields.
Fellow from Missouri said we need a combination of agricultural and
ecological solutions.
Next question. What workplan would you suggest to agencies for using the
data.
Dennis Keeney would like to see agencies getting rid of their boundaries
and tapping the energy in the community. There should be a three pronged
plan, agencies, the environmental community and agriculture.
Dr. Rabelais said her job is to do research and try to get it out to the
public. She talks to environmental organizations and the scientific
community, and doesn't know if it gets out to the agricultural community.
The Department of Agriculture could help by picking up the message and
passing it on to farmers. She sees a need for demonstration projects and
feedback to show what works with the results going to the farm and
scientific community.
Dr. Mitsch said there is a need for political support. You can't get people
in Ohio to be very concerned about the people of Louisiana. We need to have
restoration on a larger scale, like the scale of the Everglades restoration.
The agricultural community is starting to respond. The farm bill has the
potential for an enormous conservation component. Putting the coast issues
together with the farm bill is happening already
Dr. Keeney we tend to talk but not to learn. There are a lot of things that
are being done right and farmers don't always bother to tell people about
them.
To accurately account for soil nitrogen you have to look at the soil profile
in the spring as well as, see what is left in the cornstalk. This is a site
specific and labor intensive process. There are less accurate methods,
using general knowledge about how much nitrogen is present in the soil and
what is supplied by manure.
A question was asked about the origins of the data.
The data from 1905-7 was developed by both sides in a court case when
Missouri sued Illinois and the city of Chicago for polluting their water
supply. The case went all the way to the supreme court and both sides
collected and published data.
Those were not pre-development levels. Most of the increases are from 50s
60s. There is some data dating back to the 1700s. From this they have been
able to piece together the history.
The next question was whether the 2010 plan has been taken seriously.
This plan was developed by the National Academy of Science. It has not been
mentioned since it was published and we are not even 2% closer to achieving
its goals.
A date has been set for the protection of coral reefs and the questioner
does not want this to be forgotton.
Rate of restoration is one hundred times slower than it should be done
Do you approve of destroying one wetland and creating another?
The reply was that the speaker thinks it can be done but it is not being
done right. There is no follow up to see whether restoration attempts are
successful. The Army Corps of Engineers has promised to do some of this. At
best we are restoring 50,000 acres a year and this is not going to solve the
problem.
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