土壤可蚀性模拟研究中的坡长选定问题  

Selecting on Slope Length of the Soil Erodibility Simulation

作　　者：孔亚平[1] 张科利[2] 杨红丽[2] 

机构地区：[1]中国交通部科学研究院环保与安全研究中心,北京100029 [2]北京师范大学地理与遥感科学学院,北京100875

出　　处：《地理科学》2005年第3期374-378,共5页Scientia Geographica Sinica

基　　金：国家自然科学基金项目(40271072)和(40235056)资助。

摘　　要：土壤可蚀性是评价土壤对侵蚀敏感程度的重要指标,是土壤侵蚀预报的重要参数,准确评价土壤可蚀性、建立不同土壤类型的土壤可蚀性K值库具有重要意义。在总结前人研究成果的基础上,运用室内模拟试验、野外模拟降雨试验资料和野外观测小区资料,计算了不同坡长小区的K值,并对坡长对K值的影响加以分析研究。结果表明,坡长较短时,土壤可蚀性随坡长的增加而增大,且变化明显;坡长大于15m时,K值相对趋于稳定,该结论为K值模拟研究中小区的坡长选择提供了一定的理论依据。Soil erosion is now universally reckoned as an ecological environment problem, which results in land degradation and a band of ecological problems such as water pollution and flood disaster. And soil erosion is one of the most serious environmental issues in China. A key to restoring ecological environment is to control soil erosion. Soil erodibility, the susceptibility of soil to erosive forces, is generally considered an inherent soil property with a constant value. Which being an important index to evaluate the soil sensitivity to erosion, how to precisely study and evaluate soil erodibility is an important factor in soil loss prediction. It is of great significance to determine soil erodibility and develop the database for the factor K for different soil types. Since the study on the effect of soil properties on erosion began in the 1950s in China, an abundance of achievements about soil erodibility has been scored. But a number of problems still exist. The first problem is the selection of slope length to evaluate the soil erodibility, which have few studied in China for recent years. In this paper, K values for soils on plots with different lengths were computed and the effects of slope length on K were analyzed, based on the data from lab simulation experiments, field simulation experiments and field plots in Zizhou, Lishi, Fuxian and Zhangjiakou respectively. According to the results, we can concluded that though the value of soil erodibility variance with the slope length, K values increased markedly with slope length in cases of short-length slopes and K values tended to be consistent for slopes with lengths>15 m. So, when the experiments of the soil erodibility simulation are carried out, the slope length should be no less than 15m. The result may be used to select slope length in K simulation experiments.

关 键 词：土壤可蚀性 人工模拟降雨 坡面坡长 土壤侵蚀预报 

分 类 号：S157[农业科学—土壤学]