地衣对环境污染极端敏感，可作为测试空气质素的指标。

Lichens are extremely sensitive to atmospheric pollution and can be used as indicators of air quality.

youdao

地衣对环境污染极端敏感，可作为测试空气质素的指标。

Lichens are extremely sensitive to atmospheric pollution and can be used as indicators of air quality.

youdao