Pamplona-One chemical process has made a world of 7 billion people possible. Nitrogen fixation provides a staggeringly efficient way to create fertilizers with nitrogen in the air. In this process, nitrogen is combined with hydrogen to yield huge amounts of ammonia fertilizer. A Washington Post article notes 110 million tons of it are used worldwide every year.
There are serious environmental consequences to this scientific breakthrough. Ammonia fertilizer allows for exponential population growth, and enables food waste because of overproduction. Plants can only use so much of the nitrates in ammonia fertilizer. This means that as many as 50% of nitrogen-based fertilizers must go somewhere else.
One result of fugitive nitrates is eutrophication, in which water quality is severely impaired. Fugitive nitrates run into bodies of water, creating excess food for plants and algae. When the algae die they take the oxygen in the water with them.
The European Environment Agency has identified Spanish waters as especially eutrophied. A 2008 study on nitrate and pesticides report that Spain’s Mediterranian coast is particularly prone to eutrophication.
The map above shows the prevalence of another problem related to nitrates. Leaching occurs when too many soil nutrients leak through the soil and into groundwater. The graphic above features nitrate concentrations from subterrainian studied in 2006 in Navarra. The 2008 study’s plan of action recommends a more ambitious limitation on nitrate use.
Many suggestions have been made on ways to decrease nitrate runoff and leaching into groundwater. A consortium of Spanish universities and advocacy groups formed in 2011 under the name “TOPPS-PROWADIS” (translation: Protecting water from diffuse sources). The group developed a simple three step process to identifying and reducing sources of runoff.
OPPS-PROWADIS points out ways that farmers can prevent soil loss and soil runoff. They suggest implementing riparian buffer zones and windbreaks, but note the Spanish government doesn’t require them.
Other approaches focus on individual responsibility. The n-print.org website provides a way for anyone to calculate their nitrogen footprint. Harmful reactive nitrogen is created mostly by fossil fuel consumption and agriculture. A low-protein and decreased energy use are ways to limit your footprint.
Environmental conscious organizations spend significant time and resources on disseminating information about society’s carbon footprint. The nitrogen footprint and humanity’s contribution to the destruction of water quality is equally important.
(Title image via)
“Why is Your Nitrogen Footprint Important?” The Earth Institute, Columbia University
“Why we should care about our nitrogen footprint” New Scientist
“What drives the increasing eutrophication trends?” World Resources Institute
“The environmental impact of beef production” Science for Environment Policy, European Comission
“The Haber-Bosch process” Wikipedia
“Anhydrous ammonia fertilizer: abundant, important, hazardous” The Washington Post
“Situación en Navarra de la contaminación de las aguas por nitratos y pesticidas” Fundacion Centro de Recursos Ambientales de Navarra