黄土塬区坡面土壤侵蚀对全球气候变化的响应

Response of Slope Erosion to Global Climate Change on the Loess Tableland

气候变化将对黄土高原土壤侵蚀产生重要影响,评估其可能影响可为农业生产提供重要的决策依据。基于全球环流模式HadCM3,建立黄土塬区长武县2010—2039年A2a,B2a和GGa1共3种气候情景;进而使用土壤侵蚀预报模型WEPP模拟该区农田(5°和10°坡地)的土壤侵蚀变化。结果表明,2010—2039年长武县年均降水量可能增长1.8%～17.5%,年均最高和最低温度分别升高0.5℃～0.9℃和2.0℃～2.3℃。相对于目前气候下的耕作条件,2010—2039年5月和8—10月的径流量和侵蚀量显著增大;年均径流量可增长52%～119%,年均土壤侵蚀量可能增长37%～170%。气候变化将加剧黄土高原农田水土流失,需要采取相应的措施来减缓其不利影响。

Climate change will have considerable impacts on soil erosion on the Loess Plateau and assessing the possible impacts may provide useful information for agriculture production. The objective of this study was to simulate the response of slope erosion （5° and 10°） on the loess tableland during 2010--2039 based on HadCM3 （Hadley Centre Coupled Model, version 3） and WEPP （Water Erosion Prediction Project） model. GCMs predicted a 1.8% to 17.5% increase in annual precipitation, 0.5 ℃ to 0.9 ℃ rises in maximum temperature, and 2.0 ℃ to 2.3 ℃ rise in minimum temperature for the region. Compared with the present climate, the runoff and soil loss of May and August to October will increase greatly. Percent increases, as averaged for each emissions scenario and slope, ranged from 51% to 117% for annual runoff and 31% to 170% for annual soil loss. Climate change will exacerbate soil and water loss in hillslopes on the Loess Plateau and some countermeasures are necessary to mitigate the adverse effects of climate change.