作用指示

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、污染和矿藏的的监测指示作用。

The direction of luminiferous evacuation indicator is fixed in complex fire accident scene，that is difficult to play safe and effective role in the evacuation instructions.

发光型疏散指示牌的指引方向固定不变，复杂的火灾事故现场难于起到安全有效的疏散指示作用。