为了给高寒区沙化草原生态恢复提供科学依据，在玛曲高原草原选取补播改良、围栏封育和灌草结合3种植被恢复模式，通过测定土壤含水量、田间持水量、地上干物质累积和植被净初级生产力(NPP)等指标，分析不同治理模式对草原生态恢复过程中土壤水分、干物质累积和NPP变化并明确其影响。结果表明，沙化草原生态恢复过程中，土壤田间持水量10月较4月补播改良模式提高50%，灌草结合模式提高31%，围栏封育提高12%；在植被生长季，补播改良和围栏封育土壤模式的含水量均不同程度高于灌草结合，地上干物质量较围栏封育提高57.65%，较灌草结合模式提高230.10%。各恢复模式对NPP有显著影响，影响力补播改良 ＞ 围栏封育 ＞ 灌草结合，均差异显著，补播改良和围栏封育NPP分别较灌草结合提高66.05%和29.22%。可见，补播改良可提高土壤保水能力，为植被生长提高较好的水分环境，同时显著提高地上干物质累积和NPP，沙化草原生态恢复效果较好。

The Maqu alpine grassland is the main water conservation area and natural ecological barrier in the upper reaches of the Yellow River. However， the increasingly serious desertification of the grassland has threatened the ecological security of this area and even the Qinghai-Tibet Plateau and the Yellow River Basin. At present， the desertification control effect in this area is remarkable， but the influence of soil moisture and vegetation net primary productivity in the ecological restoration process needs further research. In this experiment， three types of vegetation restoration modes， including reseeding improvement， enclosure and shrub-grass combination， were selected to measure soil water content， soil field water capacity， aboveground dry matter accumulation and vegetation net primary productivity(NPP). Changes in soil moisture， dry matter accumulation and NPP in the process of grassland ecological restoration and clarifying their effects provide a theoretical basis for ecological management and restoration of desertified grasslands. The results showed that in the process of ecological restoration of desertified grassland， the field water holding capacity of the reseeding improvement model increased by 50%， the shrub-grass combination model increased by 31%， and the fence enclosure increased by 12%; in the vegetation growing season， the reseeding improvement and fence enclosure soil content increased by 50%. The amount of water was higher than the combination of shrub and grass to varying degrees， so the aboveground dry matter quality was increased by 57.65% compared with the enclosure and 230.10% compared with the combination of shrub and grass. Compared with the combination of shrub and grass， the difference was significant. The NPP of supplementary seeding improvement and enclosure was increased by 66% and 29.22%， respectively， compared with the combination of shrub and grass. It can be seen that reseeding and improvement can improve soil water retention capacity， improve a better water environment for vegetation growth， and significantly improve aboveground dry matter accumulation and NPP， and the ecological restoration effect of desertified grassland is better.

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甘肃省2020年草原生态修复治理科技支撑项目“甘南州玛曲县沙化草原生态恢复过程中土壤有机碳库变化”；甘肃省科技计划项目(20JR10RA464)。