An evaluation on using soil aggregate stability as the indicator of interrill erodibility  

作　　者：DING Wen-feng ZHANG Xun-chang 

机构地区：[1]Soil and Water Conservation Department of Yangtze River Scientific Research Institute,Wuhan 430010,China [2]USDA-ARS,Grazinglands Research Lab.,7207 W.Cheyenne St.,El Reno,0K73035,USA

出　　处：《Journal of Mountain Science》2016年第5期831-843,共13页山地科学学报（英文）

基　　金：supported by the National Natural Science Foundation of China(Grant Nos.41271303,40901135);the National Key Technology R&D Program(Grant Nos.2012BAK10B04,2008BAD98B02);the Non-profit Industry Financial Program of MWR(Grant No.201301058);the Changjiang River Scientific Research Institute of Sciences Innovation Team Project(Grant No.CKSF2012052/TB);Central public welfare scientific research project(Grant No.CKSF2013013/TB)

摘　　要：Aggregate stability is a very important predictor of soil structure and strength, which influences soil erodibility. Several aggregate stability indices were selected erodibility of four soil properties from temperate for estimating interrill types with contrasting and subtropical regions of China. This study was conducted to investigate how closely the soil interrill erodibility factor in the Water Erosion Prediction Project （WEPP） model relates to soil aggregate stability. The mass fractal dimension （FD）, geometric mean diameter （GMD）, mean weight diameter （MWD）, and aggregate stability index （ASI） of soil aggregates were calculated. A rainfall simulator with a drainable flume （3.0 m long × 1.0 m wide × 0.5 m deep） was used at four slope gradients （5°,10 °,15° and 20°）, and four rainfall intensities （0.6, 1.1, 1.7 and 2.5 mm/min）. Results indicated that the interriU erodibility （Ki） values were significantly correlated to the indices of ASI, MWD, GMD, and FD computed from the aggregate wet-sieve data. The Kihad a strong positive correlation with FD, as well as a strong negative correlation with ASI, GMD, and MWD. Soils with a higher aggregate stability and lower fractal dimension have smaller Ki values. Stable soils were characterized by a high percentage of large aggregates and the erodible soils by a high percentage of smaller aggregates. The correlation coefficients of Ki with ASI and GMD were greater than those with FD and MWD, implying that both the ASI and GMD may be better alternative parameters for empirically predicting the soil Ki factor. ASI and GMD are more reasonable in interrill soil erodibility estimation, compared with Ki calculation in original WEPP model equation. Results demonstrate the validation of soil aggregation characterization as an appropriate indicator of soil susceptibility to erosion in contrasting soil types in China.

关 键 词：Soil erodibility Interrill Aggregate stability Soil erosion 

分 类 号：S157[农业科学—土壤学]