土壤侵蚀因子的定量分析及概念模型的建立

[目的]通过对土壤侵蚀因子进行定量分析以及建立概念模型,研究云南省东川市与会泽县交界处的土壤侵蚀状况,以期为该地区土地资源利用和水土流失治理提供方法。[方法]以经验性土壤侵蚀模型———通用土壤侵蚀模型USLE(Universal Soil Loss Equation)为基础,分析并确定了土壤侵蚀的6个主要影响因子的定量指标,建立了土壤侵蚀的概念模型。使用像元乘法程序,获得像元流失量图,通过对像元流失量图和土壤侵蚀等级图的统计,确定土壤流失区域并提出解决治理方案。[结果]研究区域年平均土壤流失模数约为5 962 t/hm2,侵蚀强度属于剧烈侵蚀。土壤侵蚀等级图显示剧烈侵蚀区位于流域附近,其土壤流失极为严重,主要土地类型为荒地及裸地,坡度在30°～40°之间,未进行任何保土措施。[结论]该研究结果表明试验区域的土地利用结构与布局不合理,导致了生态环境的恶化。该流域治理的重点应是51.6%的剧烈侵蚀区,建议将坡荒地改为梯田耕作。

Quantitative Analysis of Factors Influencing Soil Erosion and Construction of Conceptual Model

[Objective] The aim was to research soil erosion in boundary areas of Dongchuan City and Huize County in Yunnan Province through quantitative analysis on factors influencing soil erosion and establishment of conceptual model,providing method for land use and treatment of soil erosion.[Method] Based on Universal Soil Loss Equation(USLE),quantitative indices of six factors influencing soil erosion were determined and the conceptual model of soil erosion was established.In addition,pixel-loss map was obtained through multiplication and soil erosive areas and the treatment schemes were proposed through statistical work of pixel-loss map and soil erosion map.[Result] In the research,annual loss modulus averaged 5 962 t/hm2,indicating the area was heavily eroded;from soil erosion map,it can be concluded that the heavily erosive area was near rivers,where wasteland and bare land dominated with slope of 30°-40°and without protective measures.[Conclusion] The research indicated that land use in the area is unreasonable and 51.6% of heavily erosive region should be paid more attention to.In addition,the wasteland is suggested to be changed into terrace cultivation.