Grassland degradation has profound negative impacts on ecological functions, local economic development, and social stability. Although there are many studies on the alpine grassland degradation in the Tibetan Plateau, the variation in the response of alpine meadows to degradation and restoration processes, and the underlying mechanisms remain poorly understood. To explore these issues, we selected nine grassland degradation levels along an increasing gradient at Zoige in the Tibetan Plateau, and collected vegetation and soil samples in August 2017 and 2018 to assess the state of the grassland before and after grazing exclusion (GE), respectively. The results showed that above-ground biomass (AGB), below-ground biomass (BGB), Shannon–Wiener index, soil water content (SWC), soil organic carbon (SOC), total nitrogen (STN), and total phosphorus decreased gradually with severe degrees of degradation, whereas soil bulk density and pH increased. SWC in the topsoil presented the sharpest change in slope along the degradation gradient, indicating that SWC was a sensitive indicator of alpine meadow degradation in this area. One-year GE evidently increased SWC, SOC, STN, AGB, and BGB in lightly and moderately degraded grasslands. The restoration efficiency of GE first increased and then decreased along the degradation gradient, with the turning point appearing at the third or fourth degradation level. Based on these results, we can conclude that short-term GE is an effective method for grassland restoration in this humid area, and should be performed at the shift from light to moderate degradation stages when the efficiency of recovery is the highest. These findings could facilitate a better approach for the restoration of degraded alpine meadow ecosystems.

草原退化对生态功能，当地经济发展和社会稳定产生深远的负面影响。尽管关于青藏高原高寒草地退化的研究很多，但高寒草地对退化和恢复过程的响应变化以及潜在的机制仍然知之甚少。为了探讨这些问题，我们选择了青藏高原Zoige沿逐渐增加的梯度的9个草地退化水平，并分别于2017年8月和2018年收集了植被和土壤样本以评估放牧排除（GE）之前和之后的草地状态。结果表明，地上生物量（AGB），地下生物量（BGB），香农-维纳指数，土壤含水量（SWC），土壤有机碳（SOC），总氮（STN），随着严重降解，总磷逐渐减少，而土壤容重和pH值增加。表土中的SWC沿退化梯度显示了最大的坡度变化，表明SWC是该地区高寒草甸退化的敏感指标。一年的GE明显增加了轻度和中度退化草地的SWC，SOC，STN，AGB和BGB。GE的恢复效率沿降解梯度先增加然后降低，转折点出现在第三或第四降解水平。基于这些结果，我们可以得出结论，短期GE是恢复该湿润地区草地的有效方法，当恢复效率最高时，应在从轻度退化到中等退化阶段的过渡阶段进行。