Using meteorological and remote sensing data and changes in vegetation cover during the wind erosion season in northern China, a revised wind erosion equation was applied to evaluate spatiotemporal variation in soil erosion and conservation since the 1990s, and to reveal the effects of the change of vegetation coverage on the wind erosion control service. The results showed that average soil erosion in northern China between 1990 and 2010 was 16.01 bil ion tons and was decreasing. The most seriously eroded areas were mainly distributed in large desert areas or low cover grasslands. Most wind erosion occurred in spring, accounting for 45.93% of total wind erosion. The average amount of sand ifxation service function for northern China between 1990 and 2010 was 20.31 billion tons. Given the influence of wind erosion forces, the service function for sand fixation cannot effectively highlight the role of sand ifxation from the ecosystem itself. The retention rate of service function for sand ifxation reveals the role of the ecosystem itself. The distribution characteristics of the soil retention rate are similar to vegetation cover, which shows a gradual decrease from southeast to northwest in the study area. Improved spring vegetation cover was observed mainly on the Loess Plateau, Qinghai-Tibet Plateau, in northern Hebei, eastern Inner Mongolia and northeast China after the implementation of ecosystem projects. The soil retention rate in most areas showed a signiifcant positive relationship with grassland vegetation in spring (r>0.7, p<0.01). The increments of ecosystem service function for various ecological systems are different. Increments for the grassland ecosystem, forest ecosystem, farmland ecosystem and desert ecosystem are 2.02%, 1.15%, 0.99% and 0.86%, respectively.%本文基于气象、遥感数据，运用RWEQ模型，结合风蚀季节的植被盖度变化对近30年的土壤风蚀量和植被的防风固沙服务功能的时空变化趋势进行了定量评估，揭示了植被盖度变化对防风固沙服务功能的影响。研究表明：中国北方多年平均土壤风蚀量为160.1亿t，并处于下降趋势，土壤侵蚀强度大的区域主要集中在各大沙漠区和植被盖度较低的草地，且春季为我国土壤风蚀的多发期，占全年风蚀量的45.93%；中国北方多年平均防风固沙量为203.1亿t；防风固沙服务功能保有率的分布特征表现为由东南到西北逐渐降低的趋势；工程实施后春季植被盖度的提升区主要集中在黄土高原、青藏高原、河北北部、内蒙古东部以及东北地区；大部分区域的春季植被盖度减小（提高）与防风固沙的服务保有率的下降（提升）呈显著正相关（r>0.7，p<0.01）；前后两个十年相比较草地生态系统的防风固沙服务功能提升幅度最大（2.02%），其次为林地（1.15%）、农田（0.99%）和荒漠（0.86%）。
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