If you keep your algae in ponds the rays do not always strike them at the best Angle and the algae sometimes shade one another if they are growing densely.

如果你把水藻种在池塘里，但是却不能以正确的角度用光线照射它们，那么如果水藻生长太过密集时，可能会相互遮挡。

youdao

If you keep your algae in ponds the rays do not always strike them at the best angle and the algae sometimes shade one another if they are growing densely.

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