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近年来,畜牧业的持续增长导致了内蒙古草原生态系统的严重退化.以往的放牧实验表明,放牧对全球植被类型存在着广泛的影响,但目前仍然缺乏研究来识别区域特定植被群落对放牧的响应.本文对内蒙古不同类型草地在不同放牧强度和放牧时长下的植被盖度(VC)、植被密度(PD)、总生物量(TB)、地上生物量(AGB)、地下生物量(UGB)和Shannon-Weaver指数(SI)进行了Meta分析.结果表明,放牧显著降低了VC、TB、AGB、UGB和PD值.放牧对内蒙古草原生物量产生的负面影响高于全球而低于全国平均水平.在中等放牧强度和时长条件下,内蒙古草甸草原TB值补偿性生长增加了40％.荒漠草原和草甸草原的SI与放牧强度呈负相关.放牧期间AGB、PD和SI的变化百分比与试验年的平均气温呈二次方关系.随着试验年年平均降水量的增加,放牧对UGB和SI的负面影响先减小后增大,放牧对VC的负面影响呈三次方关系.“,”The continuous increase of livestock production in Inner Mongolia has caused severe degradation of the grassland ecosystems in recent years. Previous grazing experiments have shown a wide range of vegetation re-sponses between the biome types on a global scale, but there is still a lack of sufficient studies to discern the rela-tive responses of a given biome type. We conducted a meta-analysis of vegetation coverage (VC), plant density (PD), total biomass (TB), above-ground biomass (AGB), under-ground biomass (UGB) and Shannon–Weaver In-dex (SI) in different grassland types in Inner Mongolia obtained under conditions of different grazing intensities and durations. The results showed that grazing decreased VC, TB, AGB, UGB, and PD significantly. Compared to the global and national average values, the negative effects of grazing to steppe biomass in Inner Mongolia were higher than that on the global scale, while less pronounced than that in China. TB of the meadow steppe in Inner Mongolia increased by 40％ under moderate grazing intensity and duration because of compensatory growth. SI of the desert and meadow steppe showed negative linear relationships with the grazing intensity in Inner Mongolia. The per-centage changes in AGB, PD, and SI to grazing showed quadratic relationships with the mean annual temperature of the experimental year. With increasing mean annual precipitation, the negative effects of grazing on UGB and SI first decreased and then increased, with that of VC and grazing showing a cubic relationship.