air pollution

Air pollution in the city had reached four times the acceptable levels.

这座城市的空气污染程度曾高达可接受标准的四倍。

There are many sources of air pollution; exhaust fumes, for example.

空气污染有许多来源, 例如废气。

Setting off firecrackers makes a tremendous noise and causes serious air pollution.

放鞭炮会产生巨大的噪,严重污染大气。

California's air pollution guidelines are stringent.

加州制定的空气污染标准很严格。

This article summarized the indicating function of bryop hyte to air pollution, heavy metal pollution and mineral resources.

综述了苔藓植物对大气污染、重金属污染和矿藏的的监测指示作。