不过，目前他们的面积和出现次数都在上升：目前发现的死水区域已经有超过400个。

But they are increasing in both size and number: dead zones have now been reported in more than 400 areas.

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对大面积“死水区域”来说化肥残留物是罪魁祸首，在墨西哥湾，氧气耗尽的死水区域几乎没有海洋生物生存。

Fertilizer runoff is responsible for a vast "dead zone," an oxygen-depleted region where little or no sea life can exist, in the Gulf of Mexico.

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当流量在一定范围内变化时，主流区下方均有漩涡低速区或死水区，该区域的大小与流量有关，其位置基本不变。

There is a whirlpool or dead zone below the main water flow zone when the flow changes and the size of which is related to flow but its location basically unchanged.

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