by Michael Graham Richard, Ottawa, Canada
Nitrate pollution around the costs of Japan and Korea could change the makeup of local marine life, both for plants and animals, according to scientists in both the U.S. and Korea. “This is the first evidence of increases in nitrate in ocean waters not in an enclosed estuary like the Chesapeake Bay,” said Raymond G. Najjar, professor of oceanography, Penn State. “These are large, very deep bodies of water and it is surprising to see increased nitrate in these large seas.”
“Normally in a marine environment nitrate is the limiting factor, but increased nitrate in the ocean can spur growth and create a situation where phosphorus becomes the nutrient in short supply,” says Raymond G. Najjar, professor of oceanography, Penn State. “This change in nutrients could favor organisms that are better suited for high nitrate and low phosphorus.” […]
The researchers suggest that their results have broader applicability. “The observed trends may be extrapolated to the coastal seas of the North American Atlantic Ocean and the North, Baltic and Mediterranean Seas, which have received ever-increasing amounts of anthropogenic atmospheric nitrate deposition and river-borne nitrate, comparable to those absorbed by coastal and marginal seas of the northwestern Pacific Ocean.”
Nitrate is a naturally occurring chemical that is left after the breakdown or decomposition of animal or human waste, and when present in large enough quantities it can be toxic to marine life. But even in lower concentrations, it can change the local environment enough to negatively affect ecosystems that have evolved with different nutrient concentrations.
(Source: www.treehugger.com )