题干

在某水生生态系统中,分布有水鸟、藻类、芦苇等动植物,某些水鸟具有秋季迁徙的习性.下列叙述不正确的是(    )

A:该水生生态系统的物种数量随季节而发生变化

B:芦苇和藻类垂直分布导致该系统对光能的利用率降低

C:藻类和芦苇等固定的能量是流经该生态系统的总能量

D:动植物残体被微生物分解后可产生含氮化合物

上一题 下一题 0.0难度 选择题 更新时间:2010-11-22 10:49:38

答案(点此获取答案解析)

B

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