Difference between a refugee and an illegal immigrant

A refugee has filed paper work and is seeking safety from for example war and an illegal immigrant has no necessary paper work and are usually hidden

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When a lake, river or other aquatic  system  becomes  eutrophic, it can have serious negative effects on other organisms like fish, birds and even people.if an algal bloom is so bad that it causes wide-spread death  in  the  water, the organisms that die will all sink to the bottom and start to decompose.