Thomas McGann
Env. & Pol.
11-15-2013
Article Annotation 1
The main argument in this article is that synthetic nitrogen based fertilizers are destroying
marine ecosystems, and must be regulated. Arguments against increased corn production for
biofuels and increased meat production were also presented.
A quote to support the main argument would be: “What is clear is that a significant
portion of such fertilizer is still making its way through the soil and water to the sea. As a result,
algae and other microorganisms take up the nitrogen, bloom and, after they die, suck the oxygen
out of coastal waters.” This shows specifically how the nitrogen based fertilizers negatively our
marine ecosystems. Another quote to support the argument against increased corn production is,
“The bulk of this nitrate comes from fertilizer running off agricultural fields. Scientists warn that
a boom in crops such as corn for biofuel will only make matters worse.” If corn production is
increased, this will directly increase the amount of nitrogen based pollutants in the marine
ecosystems.
A study conducted by aquatic ecologist Patrick Mulholland shows how nitrogen overload
can reduce the effectiveness of streams at removing nitrogen based pollutants. A unique,
concentrated nitrogen isotope was released into select streams ranging from heavily altered urban
water ways, to pristine streams. The isotope was tracked downstream and the amount collected at
the bottom indicated how much was filtered out. Mulholland found that the already heavily
polluted urban waterways only eliminated 16 percent while the cleaner streams were able to
eliminate nearly 43 percent. This shows that heavily polluted waterways cannot filter pollutants
as effectively leaving the nitrogen to be consumed by microbes and algae. This leads to algae
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Thomas McGann
Env. & Pol.
11-15-2013
blooms which use all of the oxygen in the surrounding area leaving a large “dead zone” of
uninhabitable waters.
Another piece of evidence is the increased use, and growing of corn. In 2007 90 million
acres of corn was planted for the first time since the 1940’s. Because agricultural runoff is the
main source of nitrates, the increased production of corn to subsidize biofuel production will lead
to huge dead zones at the mouths of most rivers worldwide. There is already a dead zone at the
mouth of the Mississippi River the size of New Jersey.
The increased production of beef has also indirectly led to fertilizer pollution. Cows
being fed corn have led to an increased use of corn similar to biofuels. With nitrogen levels
expected to rise 34 percent by 2022 in the Mississippi River Basin due to increased farming and
fertilizer use, regulations really need to be implemented now.
This article will benefit our project by explaining how fertilizers negatively affect our
environment, and by displaying some of the existing consequences. There is a lot of quantitative
data in this article that can be used to make people truly understand the problem. Things like the
7’700 square mile dead zone at the mouth of the Mississippi River, or the percentages of nitrates
filtered by the different types of waterways. The expected increase in water based nitrates by
2022 will also be beneficial, as will the explanation of how dead zones are created.
-Biello, David. "Fertilizer Runoff Overwhelms Streams and Rivers--Creating Vast "Dead
Zones": Scientific American." Fertilizer Runoff Overwhelms Streams and Rivers-Creating Vast "Dead Zones": Scientific American. Scientific American, n.d. Web. 11 Nov.
2013. <http://www.scientificamerican.com/article.cfm?id=fertilizer-runoff-overwhelmsstreams>.
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