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Foul fare for fish

作者:归顶降    发布时间:2019-03-07 06:13:00    

By Andy Coghlan A FEW tankfuls of fish could put a stop to the devastating blooms of algae caused when sewage works discharge effluent into rivers and lakes. Most sewage works remove solids from raw sewage and get rid of organic matter with the help of sludge-dwelling bacteria. But few remove dissolved phosphorus and nitrogen from detergents and fertilisers. When too much of these nutrients get into fresh water, they can trigger explosive growths of algae. All the oxygen in the water is used up when the algae decompose,

 

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