Fertilizer and sewage runoff cause the worst marine pollution, but we can reverse their effects
By Rowan JacobsenPosted 05.06.2011 at 10:03 am 15 Comments
Marine pollution takes many forms, from the millions of gallons of oil that run off our highways each year to the Great Pacific Garbage Patch, a massive gyre of floating plastic trash. But the most devastating pollutants are the nitrogen and phosphorus found in our fertilizer and sewage. When too much of either washes downstream, coastal waters become choked with heavily fertilized algae, which then dies and decomposes, consuming the oxygen in the water and asphyxiating animal life. This process, called eutrophication, has created at least 405 “dead zones” worldwide.
Publishing in the journal Nature, a group of 29 scientists have established a comparative scale for rating the immediate threat posed by nine environmental hazards--everything from climate change to ocean acidification. And while our warming climate gets most of the attention, more immediate problems may be brewing in our intensifying lack of biodiversity and out-of-whack nitrogen cycle.
Save coastal marshes and clean up polluted waterways with plant-covered rafts
By Rena Marie Pacella; Illustrations by Graham MurdochPosted 06.29.2007 at 2:00 am 1 Comment
Where: Coastal areas
Cost: $800 million per square mile of island
The Problem The wetlands are losing ground. Crops and condos are rapidly overtaking much of the waterlogged land-home to thousands of bird and animal species-while pollution and sea-level rises take care of the rest. With this loss comes drastically reduced water quality, increased flooding of surrounding areas and the looming specter of the extinction of many species.