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When EPA implemented the Clean Water Act, it
used an essential test incorrectly and ignored the nitrogenous (urine and
protein) waste in sewage, while this waste is a fertilizer for algae and
contributes to the 'nutrient' pollution now in most open waters. Although EPA
acknowledged some of the problems caused by this test in 1984, it never
corrected the test. This petition hopefully will force EPA after 30 years to
correct the test, so we finally can implement the CWA as intended and possible.
News release American
Chemical Society:
Friend and foe: Nitrogen pollution's
little-known environmental and human health threats
DENVER, Aug. 28, 2011 Billions of people owe their lives to nitrogen
fertilizers a pillar of the fabled Green Revolution in agriculture that
averted global famine in the 20th century but few are aware that nitrogen
pollution from fertilizers and other sources has become a major environmental
problem that threatens human health and welfare in multiple ways, a scientist
said here today.
"It's been said that nitrogen pollution is the biggest environmental disaster
that nobody has heard of," Alan Townsend, Ph.D., observed at the 242nd National
Meeting & Exposition of the American Chemical Society (ACS), being held here
this week. Townsend, an authority on how human activity has changed the natural
cycling of nitrogen to create a friend-turned-foe dilemma, called for greater
public awareness of nitrogen pollution and concerted global action to control
it. He spoke at a symposium on the topic, which included almost a dozen reports
(abstracts of each presentation appear below) by other experts.
"Awareness has grown, but nitrogen pollution remains such a little-recognized
environmental problem because it lacks the visibility of other kinds of
pollution," Townsend explained. "People can see an oil slick on the ocean, but
hundreds of tons of nitrogen spill invisibly into the soil, water and air every
day from farms, smokestacks and automobile tailpipes. But the impact is there
unhealthy air, unsafe drinking water, dead zones in the ocean, degraded
ecosystems and implications for climate change. But people don't see the
nitrogen spilling out, so it is difficult to connect the problems to their
source."
Townsend described the scope and the intensification of the nitrogen pollution
problem as "startling." He noted that nitrogen inputs to the terrestrial
environment have doubled worldwide during the past century. This increase is due
largely to the invention and widespread use of synthetic fertilizer, which has
revolutionized agriculture and boosted the food supply.
The concern focuses on so-called "reactive" nitrogen. Air contains about 78
percent nitrogen. But this nitrogen is unreactive or "inert," and plants can't
use the gas as a nutrient. In 1909, chemist Fritz Haber developed a way to
transform this unreactive gas into ammonia, the active ingredient of synthetic
fertilizer. By 2005, human activity was producing about 400 billion pounds of
reactive nitrogen each year.
"A single atom of reactive nitrogen can contribute to air pollution, climate
change, ecosystem degradation and several human health concerns," Townsend said.
He is an ecology and evolutionary biology professor at the
University
of
Colorado at
Boulder.
Damage to the ecosystem a biological community interacting with its nonliving
environment includes water pollution and reduced biological diversity,
including the loss of certain plant species.
Though the full extent is currently unknown, nitrogen pollution can impact human
health. Reactive nitrogen is a key contributor to air pollution, including the
formation of ground-level ozone, which is a well-known health risk. Recent
estimates suggest that nitrogen-related air pollution costs theU.S.
well over $10 billion per year in both health costs and reduced crop
growth. And though less well studied, high nitrogen levels in water can cause a
variety of health concerns, ranging from the effects of drinking water nitrate
to the potential to alter the risks of several human diseases.
Increased nitrogen levels also have implications for climate change, Townsend
noted. Excess nitrogen can affect the rate of climate change in multiple and
opposing ways. One the one hand, it leads to more warming via the greenhouse gas
nitrous oxide, but on the other hand, it can reduce warming by fueling extra
plant growth and by forming substances called reflective aerosols in the
atmosphere, the scientists noted.
"The net effect of these processes remains uncertain, but appears to result in
minor cooling presently," Townsend said. However, he noted that excess nitrogen
also has large and clear consequences for some worrisome impacts of a changing
climate, notably air and water pollution.
"Climate change is expected to worsen each of these problems worldwide, but
reduction of nitrogen pollution could go a long way toward lessening such
climate-driven risks," he added.
"We're just now starting to recognize the scope of the problem," said Townsend.
"But the good news is that there are many opportunities for us to lessen the
problems. These include ways in which chemists can help, ranging from the
development of new technologies to reduce nitrogen's impact to new measurement
technologies and techniques that can better diagnose the problems we face with
nitrogen."
He outlined several possible solutions to the problem. They include continued
and greater support for technologies that remove or reduce reactive nitrogen
formation during fossil fuel burning and incentives that can encourage farmers
to be more efficient with their fertilizer use. The latter could include
subsidies that reward the application of environmental practices that reduce
nitrogen levels, he said.
Several other solutions exist for improving the efficiency of agricultural
nitrogen use, Townsend added. "In many ways, we already know how to do it the
problems are largely about finding the political and cultural means to implement
these new practices," he said.
###
The National Science Foundation and the David & Lucile Packard Foundation
provided funding for Townsend's research.
The American Chemical Society is a non-profit organization chartered by the U.S.
Congress. With more than 163,000 members, ACS is the world's largest scientific
society and a global leader in providing access to chemistry-related research
through its multiple databases, peer-reviewed journals and scientific
conferences. Its main offices are in
Washington,
D.C., and
Columbus,
Ohio.
To automatically receive news releases from the American Chemical Society
contact
newsroom@acs.org.
ABSTRACTS:
Nitrogen and the Human Endeavor
Alan R
Townsend1 , Professor, University of Colorado at Boulder, Department of
Environmental Studies, INSTAAR, 1560 30th Street, Boulder, CO, 80303, United
States, 303-492-6865, 303-492-6388,
townsena@colorado.edu
Modern human society relies upon extraordinary disruptions to several global
biogeochemical cycles. Transformation of one such cycle nitrogen (N) was a
pillar of the Green Revolution and remains necessary to ensure future food
security, but also creates multiple negative environmental and socio-economic
consequences. Both the scale and pace of human changes to the N cycle are
startling: in two human generations, we have more than doubled "reactive" N
inputs to the terrestrial biosphere. Many of nitrogen's harmful effects are a
product of its diverse chemical nature; a single atom of human-created reactive
nitrogen can contribute to air pollution, climate change, ecosystem degradation
and several human health concerns as it passes among multiple redox states. This
talk will review human changes to the global N cycle and their major
consequences, and then present examples of how society can pursue a more
sustainable relationship with this essential element.
Anthropogenic impacts recorded in the isotopes of atmospheric nitrate
Meredith
Hastings1 , Brown
University, Dept of Geological Sciences/Environmental Change
Initiative, 324 Brook Street, Box
1846, Providence,
RI, 029012,
United States, 401-863-3658,
meredith_hastings@brown.edu
Atmospheric nitrate is the result of nitrogen oxide emissions and reactions
between NOx and major oxidants such as ozone and hydroxy compounds. Sources of
NOx include fossil fuels combustion, biomass burning, biogenic processes in
soils, lightning and stratospheric oxidation of nitrous oxide. With significant
variability in latitude and altitude, distinguishing source contributions,
particularly from the natural sources of NOx,is a challenge. The isotopic record
of nitrate in an ice core from
Greenland, reveals a clear change in the δ15N of nitrate that
reflects changes in the sources of nitrate. The δ15N of nitrate decreases from a
pre-industrial value of +11 (vs. air) to significantly lower values in the last
decade (~ -1). This decrease is highly correlated with fossil fuel emissions
estimates since 1750, but may also reflect soils emissions related to
agricultural changes over this time period. The ability to trace the sources of
NOx, in the modern environment and over time, has implications for studies of
acid deposition, air quality, eutrophication, biogeochemistry and paleoclimate.
Poorly known roles of iron and other metals in the nitrogen cycle
Eric A
Davidson1 , The Woods Hole Research Center,
149 Woods Hole Road, Falmouth,
MA, 02540-1644,
United States, 15084441532, 15084448132,
edavidson@whrc.org
The nitrogen cycle includes numerous processes that alter the oxidation state of
the N atom, from -3 in ammonia to +5 in nitrate. Iron and other metals are known
to play roles in some of the enzymatic reactions of the N cycle. Abiotic
reactions involving iron are thought to affect nitrate in aquatic systems, but
their role in soil processes is less well understood. The fate of nitrate from
atmospheric deposition onto forest soils remains a mystery. Abiotic reduction of
nitrate by ferrous iron is thought to be thermodynamically unfavorable under the
acid conditions of forest soils, and yet there is evidence for abiotic
consumption of nitrate. Another mystery is reduction of atmospheric nitrous
oxide in well drained soils, which is unlikely to be due to classical biological
denitrification, with a tantalizing hint that it is more common in iron-rich
soils.
Fertilizer management effects on nitrous and nitric oxide emissions from
cropping systems of the upper Midwest U.S.
Rodney T
Venterea1,2 , USDA-ARS, Soil and Water Management Research, 1991 Upper Buford
Circle, St. Paul, MN, 55108, United States, 612-6244-7842,
venterea@umn.edu
Increases in atmospheric N2O concentrations, driven largely by application of
nitrogen fertilizers, continue at a steady rate with important effects on
climate forcing and stratospheric ozone depletion. Fertilizer-derived NO
emissions influence local and regional atmospheric chemistry and air quality.
Corn production consumes more than 40% of all N fertilizers applied to crops in
the
U.S.
and represents the largest single source of fertilizer-derived soil N2O and NO
emissions relative to other crops. While reduction in N fertilizer application
rates may be an effective means of reducing these emissions, this may come at
the cost of decreased yields. We have been examining the use of alternative
practices that could reduce emissions without necessarily reducing N inputs or
crop yields, such as modification of fertilizer source, placement or timing, and
alteration of tillage and other management regimes. We will present a summary of
our recent studies in this regard and discuss the challenges in developing
management recommendations for effective mitigation of N emissions and
enhancement of N use efficiency.
Understanding the role of the nitrogen cycle in the climate and earth systems
Elisabeth A
Holland1 , Senior Scientist, Dr., National Center for Atmospheric Research,
Atmospheric Chemistry Division, 3090 Center Green Dr., Boulder, CO, 80301,
United States, 303-497-1433,
eholland@ucar.edu
The bio-atmospheric exchange of reactive nitrogen has increased three- to
five-fold since 1850 as a result of intensified fossil fuel use and agriculture.
The changing nitrogen cycle is poised at the crossroads of climate change, air
and water quality, agriculture, ecosystem function and sustainability making it
a truly global issue. The carbon cycle has been in the limelight of public
attention. Yet, the nitrogen cycle is central to the atmospheric concentrations
of four of the top five greenhouse gases, carbon dioxide, methane, tropospheric
ozone and nitrous oxide, and to the concentration of atmospheric aerosols that
provide radiative cooling offsets. State of the art coupled carbon, nitrogen and
climate models have been developed in the last few years enabling a more
complete evaluation of the climate impact of the nitrogen cycle. As global
citizens, do we need to think about our nitrogen footprint AND our carbon
footprint?
Sluggish ocean nitrogen budget during the last ice age
Haojia Ren1 ,
Princeton University,
Department of Geosciences, Guyot Hall,
Princeton, NJ,
08544, United States,
609-933-0094,hren@princeton.edu
Using the "persulfate/denitrifier" strategy for analyzing the 15N/14N of
nanomole quantities of organic N, we are exploring the paleoceanographic utility
of the organic matter bound within the calcium carbonate shells of planktonic
foraminifera. In deep sea sediment cores from the tropical
Atlantic, we find that the 15N/14N of
foraminifera-bound organic matter from the last ice age is higher than that from
the current interglacial, indicating higher nitrate 15N/14N in the ice age
Atlantic thermocline. This and species-specific differences are best explained
by less N fixation in the
Atlantic during the last
ice age. The N fixation decrease was most likely in response to a previously
recognized reduction in the ocean's loss rate of fixed N during ice ages. This
ice age reduction in N fixation would have worked to balance the ocean N budget,
at lower ice age rates of input and loss, and to curb ice age-to-interglacial
change in the ocean's fixed N inventory.
Recent trends in reactive nitrogen: Air quality, deposition, and climate change
Robert W
Pinder1 , US Environmental Protection Agency, Atmospheric Modeling and Analysis
Division, Mail Drop E243-01, Research Triangle Park, NC, 27711, United States,
919-541-3731, UNITED STATES,
pinder.rob@epa.gov
Reactive nitrogen emissions, including nitrogen oxides (NOx) and ammonia (NH3),
are dangerous air pollutants that degrade human health, deteriorate ecosystem
function and exacerbate climate change. After decades of persistently high
levels, nitrogen oxide emissions have been decreasing over the past 10 years.
This is largely due to more effective emission control systems on vehicles and
power plants. The results of these emission reductions are evident in the
satellite record, precipitation measurements and atmospheric concentrations.
Since NH3 is largely an unintended byproduct of industrial agriculture, these
emissions have not decreased in recent years. This talk will consider the
impacts of these recent emission trends on air quality, nitrogen deposition and
climate change.
Nitrogen deposition, carbon storage, and climate
Christine L.
Goodale1 , Cornell University, Ecology & Evolutionary Biology, E215 Corson Hall,
Ithaca, NY, 14853, United States, 607-254-4211,clg33@cornell.edu
Human activities have greatly accelerated the emissions of reactive nitrogen to
the atmosphere and the deposition of this N onto downwind ecosystems. This N
deposition was long expected to enhance forest growth and C sequestration, but
observational evidence of deposition-induced stimulation of regional forest C
sequestration was lacking until recently. The response of forest soil C storage
is even less well-understood and quantified, but observational evidence is
accumulating to indicate that N deposition suppresses decomposition in many
forest soils. We combine recent evidence of N-induced forest C sequestration to
provide quantitative estimates of national- and global C sinks in trees and
soils. These observations are now being used to develop and test local and
global-scale models of C, N and climate.
Response of sensitive freshwater ecosystems to reactive nitrogen deposition in
western North America
Sarah A
Spaulding1,2 , USGS, Fort Collins Science Center, 2150 Centre Ave., Building C,
Fort Collins, CO, 80526, United States, 303-492-5158,Sarah.Spaulding@Colorado.EDU
We discuss the evidence for widespread, synchronous and threshold changes in
sensitive freshwater ecosystems as the result of reactive nitrogen deposition in
western North
America. Analyses of bulk N stable isotopes from multiple
paleolimnological studies using lake sediments support observations of increased
delivery of dissolved inorganic nitrogen with concurrent depletion of δ15N, a
marker of anthropogenic sources. In nutrient poor aquatic ecosystems, including
sensitive high elevation lakes, algae were historically limited by N. With
increasing deposition of N, primary productivity has increased and algal species
composition has shifted. In some cases, algal growth is no longer limited by N.
As a result, these aquatic ecosystems are changing from oligotrophic (low
nutrient) systems to mesotrophic (mid nutrient) systems. The eutrophication of
lakes by deposition of atmospheric N is of great concern in the west, and there
is evidence that many unproductive lakes are experiencing increased biological
production due to atmospheric N.
Framework for action on nitrogen: Lessons from the
California
Nitrogen Assessment
Thomas P
Tomich1 , University of
California, Davis,
Agricultural Sustainability Institute,
One Shields Ave, Davis,
CA, 95616,
United States, 530-752-2379,
tptomich@ucdavis.edu
This paper will report the results of the California Nitrogen Assessment, a
major integrated scientific assessment which will be completed in June 2011. It
will differentiate between what is scientifically well known and what is more
uncertain about the causes and consequences of the flows of reactive nitrogen
(Nr) into, out of and among major sectors in
California
focusing on agriculture. This paper will also consider a comprehensive
range of agricultural practices and policy options that could more effectively
balance the benefits of Nr with its costs for
California, the most agriculturally
productive, biologically diverse and populated state in the
U.S.A.
Contact: Michael Bernstein
m_bernstein@acs.org
303-228-8532 (Aug. 25-Sept. 1)
202-872-6042 (Before Aug. 25)
Michael Woods
m_woods@acs.org
303-228-8532 (Aug. 25-Sept. 1)
202-872-6293 (Before Aug. 25)
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