Washington DC (SPX) May 19, 2011
Nitrogen pollution in our coastal ecosystems, the result of widespread use of synthetic agricultural fertilizers and of human sewage, leads to decreased water transparency, the loss of desirable fish species, and the emergence of toxic phytoplankton species-such as the algae behind the renowned "red tides" that kill fish.
The effects are particularly pronounced in the Gulf of Mexico and the Caribbean.
A study published in the journal Global Change Biology finds that while fertilizer has been the dominant source of nitrogen pollution in Caribbean coastal ecosystems for the past 50 years, such pollution is on the decline, thanks in part to the introduction of more advanced, environmentally responsible agricultural practices during the last decade. But now, sewage-derived nitrogen is increasingly becoming the top source of such pollution in those areas.
"We can't simply say our coastal ecosystem is being polluted by nitrogen," said Kiho Kim, one of the study's authors and chair of environmental science at American University. "The consequences may be the same, but differentiating the source of the pollutants is critical to crafting sustainable solutions-you can't fix a problem if you don't know what's causing it."
Through a chemical analysis of 300 coral samples from the Smithsonian Institution's National Museum of Natural History's Invertebrate Zoology Collection, Kim and some American University graduate students reconstructed a record of nitrogen inputs into the Caribbean over the last 150 years. Agricultural and sewage pollution create different signatures in organisms like coral.
"We determined that poor stormwater management and wastewater treatment were really to blame over the last decade for nitrogen pollution in the Caribbean," said Kim. "Our next step is to document this process in action."
To do this, Kim will focus on coral samples from the coastal areas of Guam, a small Pacific island that during the next four years will experience a population increase of 20 percent as the U.S. military relocates Marines from Okinawa, Japan to Guam.
Guam already has poor waste water infrastructure, and the influx of military personnel will further strain the island's resources. For Kim, the transition presents a unique opportunity to observe and document, in real time, the impact of increased sewage-derived nitrogen on the health of the coral reefs. He has already collected some baseline data in Guam, thanks to a small grant from the National Oceanic and Atmospheric Administration.
The Marines' translocation has recently slowed a bit, partially because of the earthquake and tsunami in Japan.
"This means that we will have time to collect more comprehensive baseline data," said Kim, who will return to Guam this summer to perform another set of sample and data collections with his colleague at the University of Guam.
Share This Article With Planet Earth
Water News - Science, Technology and Politics
Heavy rains a suspect in sharks' deaths
San Francisco (UPI) May 18, 2011
A rash of deaths among leopard sharks in San Francisco Bay may be linked to heavy winter rains diluting saltwater in the bay, wildlife officials say. State biologists investigating a rash of leopard shark casualties over the past month say they think the body chemistry of the fish may be thrown fatally off balance by the torrents of fresh water flowing into shoreline lagoons where they ... read more
Quake-hit New Zealand takes axe to public services|
Japan tells tourists says 'it's safe' to come back
US extends relief for undocumented Haitians
Japan TEPCO workers enter reactor building
Amazon selling more Kindle books than print books
China slaps export quota on rare earth alloys
Physicist accelerates simulations of thin film growth
Research questions reality of supersolid in Helium-4
Heavy rains a suspect in sharks' deaths
Floating 'green' golf course for Maldives
Greenhouse ocean study offers warning for future
Ocean warming detrimental to inshore fish species
Research aircraft Polar 5 returned from spring measurements in the high Arctic
Denmark plans claim to North Pole seabed: foreign minister
Ecological impact on Canada's Arctic coastline linked to climate change
Canada PM's Arctic stand 'frosty rhetoric'
New method of unreeling cocoons could extend silk industry beyond Asia
Post-Mubarak Egypt 'running out of food'
Exploding melons sow new China food fears
Livestock genes could protect against one of Africa's oldest animal plagues
5.9-magnitude quake hits northwest Turkey: one dead
US predicts up to 10 Atlantic hurricanes this season
Historic US flooding turns deadly
Australian flood costs top $6 billion
Sudan stages new Darfur air strikes: UN
British PM rejects pressure on aid budget
Mozambique wages war on man-eating crocs
Humanity can and must do more with less
The roots of memory impairment resulting from sleep deprivation
Clubbers can smell a good nightspot
Sporadic mutations identified in children with autism spectrum disorders
Computer program aids patients in end-of-life planning
|The content herein, unless otherwise known to be public domain, are Copyright 1995-2010 - SpaceDaily. AFP and UPI Wire Stories are copyright Agence France-Presse and United Press International. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by SpaceDaily on any Web page published or hosted by SpaceDaily. Privacy Statement|