利用CMIP5耦合模式历史情景和土地利用情景结果，定量评估了模拟的土地利用变化对20世纪中国地区气候干湿变化的影响。结果表明，土地利用的变化加剧了20世纪中国地区干旱化的进程，其贡献约为1/3。其中，湿润区具有显著变干的趋势，土地利用变化的贡献约为35.4%；半干旱区显著变干，土地利用对半干旱地区变干的贡献不显著；两种情景下干旱区干湿变化都不显著。在土地利用情景下，中国地区土地利用的变化主要表现为一级土地的减少和牧草用地的增加，二者分别从国土面积的72.7%和12.9%（1901年）变为36.0%和41.9%（2004年），且1950年代之后变化速率显著增大。其中大面积显著的变化主要发生在青藏高原、内蒙古以及新疆北部地区，导致这些地区降水减少、温度降低，而降水减少带来的干旱化作用大于温度降低带来的变湿作用。%The contribution of land use change to the dry/wet trends in China during the 20th century is assessed on the basis of climate simulations of coupled models under historical and land use scenarios provided by the fifth phase of the Coupled Model Intercomparison Project (CMIP5). The results suggest that land use change may have enhanced aridification in China during the 20th century, with a contribution of approximately one-third. For humid regions, the contribution is approximately 35.4%. Although the drying trend in semi-arid regions is significant, the influence of land use is not detectable. For the arid regions, the drying trend is not significant. The land use change scenario in China is featured by a loss of primary land and increase of pasture throughout the 20th century, from 72.7%and 12.9%of the total national land in 1901, respectively, to 36.0%and 41.9%in 2004, with the enhanced changing rate lasting into the latter half of the century. This type of land use change occurs mainly in the Qinghai–Tibetan Plateau, Mongolia, and northern Xinjiang, causing decreasing trends in both temperature and precipitation. The drying trend due to decreasing precipitation overwhelms the effect of cooling temperatures.
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