As residential development takes
over natural habitats, wastewater runoff is becoming an enormous
problem. If current trends of nitrogen loading continue, algae will
take over coastal waterways, deeper water will become anoxic and
fish will die.
Excessive use of chemical fertilizers and manure on
agricultural land is the main source of groundwater contamination
(Maeda et al. 2003). However, fertilizer used on home lawns
can have a significant impact too.
If the town of Falmouth,
Massachusetts, is any indication, over 15% of the nitrogen that
seeps into the water is from residential fertilizer use (Peterson).
Though not the major component of nutrient pollution, residents can
easily change their lawn care practices to reduce the amount of
nitrogen runoff. Tons of nitrogen rich fertilizer is dumped on front
lawns at dosages higher than used in agriculture per unit of ground
Although nitrogen makes up nearly 80% of the mass of
the Earth's atmosphere, it is in the non-reactive N2 gas form. In
the early 20th century, people began to realize that the increasing
human population was not being met by an increase in food
production. In 1913, the invention of the Haber-Bosch process
allowed anthropogenic fixation of nitrogen (Galloway and Cowling
2002). The use of inorganic fertilizers increased dramatically after
World War II to increase agricultural output. Currently, the
combined affect of nitrogen entering the environment from food
production, fossil fuel combustion
and the Haber-Bosch process is
twice the amount of nitrogen fixed biologically by microbes
(Galloway et al. 2002).
The Haber-Bosch process created an unlimited supply of
nitrogen available to grow food in the form of inorganic
fertilizers. However, fixing nitrogen for the fertilizer requires
energy gained from the burning of fossil fuel, adding to inorganic
fertilizer's negative environmental impact (Kramer et al. 2001).
Today, about half of the food eaten globally is produced using
chemical fertilizers (Galloway and Cowling 2002) and half of
the inorganic fertilizers ever used on the Earth were used in the
last fifteen years.
NO (Nitrogen), a greenhouse gas, not only
contribute to global climate change, but also decrease stratospheric
ozone. Also, the release of nitrogen oxides increases tropospheric
ozone injuring croplands and natural ecosystems and, with
increased particulate matter, causes human respiratory and cardiac
diseases (Galloway < et al