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There is a debate about the status and causes of rangeland changes in Mongolia. The primary cause is thought to be livestock population growth and decline of rainfall is a possible secondary cause. Field studies have focused on vegetation responses to grazing across a wide range of environmental gradients and the relative importance of abiotic and biotic factors on vegetation. Remote sensing studies have reported widespread degradation, but describe different extents and causes of rangeland change. Remote sensing studies can cover large areas and long time periods but require field validation. This study combines a broad -scale field data collection (143 winter pastures in 4 ecological zones) with a temporally sizeable remote sensing analysis to assess the long term effects of livestock on vegetation, forage quality and soils in Mongolia. At the field level, we measured the effects of livestock grazing around piospheres or grazing gradients created across winter pastures. In order to measure long-term grazing and climate effects, we quantified trends in livestock grazing intensity, biomass (MODIS NDVI) and climate variables to analyze change from 2000-2013 at 26 winter pastures in the mountain and forest steppe, steppe and desert steppe ecological zones. Our results show that grazing-induced changes were largest in the steppe (170 mm rainfall), moderate in the mountain and forest steppe (239 mm rainfall) and desert steppe (131 mm rainfall) and least in the eastern steppe (258 mm rainfall). Our study also showed that NDVI-derived biomass tracked grazing more closely in the mountain and forest steppe and steppe than in the desert steppe, as predicted by non-equilibrium rangeland dynamics theory.