Polluted sediments kill corals
This NASA satellite image shows sediment-laden water pouring into the Gulf of Mexico from the Atchafalaya River. The research explains why some corals survive sedimentation events, but others are wiped out. Image: NASA Earth Observatory The speed of coral death increases alarmingly if colonies are flooded with polluted rather than "clean" sediments, an international team of researchers writing in a prestigious scientific journal has found.The work solves one of the big mysteries of coral research: why some corals die suddenly after sedimentation events, while others survive.The findings, published in the Proceedings of the National Academy of Sciences, show that preventing sediments contaminated with pollutants such as phosphorous and nitrogen from entering coral reef areas is essential for reef health.In coastal areas with excessive soil erosion, where rivers flush nutrients, organic matter and sediments to the sea, corals can die very quickly. Dr. Katharina Fabricius, a principal research scientist at the Australian...