平抑作用 meaning in Chinese

leveling

But variation of the co ; concentration in the bottom soil show that sink effect of carbonate rock on the soil air co2 ( 2 ) the diurnal observation results of soil co2 dynamics in the different vegetation show that the soil co2 concentration in the bare land is sensitive to environment , but the soil co ; concentration in the other experimental site , which covered with vegetation , restrain the variation
在土壤?大气界面上，土壤表层可为大气提供游离co _ 2 ；而土壤深部co _ 2浓度的变化则显示下覆碳酸盐岩对co _ 2有吸收作用。 ( 2 )在不同植被系统中，土壤co _ 2昼夜动态变化进程不同。观测资料表明：裸地对外界环境的变化相当敏感，而有植被覆盖的竹林和草甸对土壤co _ 2浓度动态变化有平抑作用。