模拟降雨条件下黑土溅蚀与团聚体分选特征  

Splash Erosion and Selective Characteristics of Aggregate for Typical Black Soil Under Artificial Rainfall Condition

作　　者：周一杨[1] 王恩姮[1] 陈祥伟[1] 

机构地区：[1]东北林业大学,哈尔滨150040

出　　处：《水土保持学报》2008年第6期176-179,共4页Journal of Soil and Water Conservation

基　　金：教育部博士点基金项目(20060225012);黑龙江省重大科技攻关项目“丘陵黑土区水土保持林构建与流域综合治理技术研究”(GA06B302-3)

摘　　要：以典型黑土耕地表层土壤为对象．通过对溅蚀量、水稳性团聚体组成、团聚体平均重量直径（MWD）以及团聚体富集率（ER）等指标的测定、计算与分析，研究了人工模拟降雨条件下典型黑土溅蚀过程中团聚体粒级分布及其分选特征。结果表明：溅蚀盘内不同收集区域（上坡、下坡）溅蚀量及净迁移量均与溅蚀距离呈显著指数递减关系，R^2值达0．8344～0．9911；土壤团聚体富集率的变化幅度范围为0．00～1．79，溅蚀对团聚体产生富集作用与损耗作用的临界粒级为1．0mm溅蚀颗粒土壤水稳性团聚体组成上表现出在水平空间上随距离的增加，小粒级团聚体比例逐渐增加的趋势，2～5mm粒级的团聚体只出现在上坡的0～5cm和下坡的0～10cm范围之内，1～2mm粒级的团聚体在上坡的最大分布距离仅为28cmMWD变化幅度为0．32～O．80mm，并随溅蚀距离的增加而减少，其中下坡10～17cm范围内的MWD分别与0～10cm和17～40cm范围内MWD的差异达到显著水平（P〈0．05）。研究结果为进一步系统研究黑土侵蚀发生规律与水土流失治殚提供了参考。An experiment was conducted to study the splash erosion and selective characteristics of aggregates for the typical black soil under artificial rainfall condition in terms of splash erosion amount, fraction of water-stable aggregate, mean weight diameter （MWD） of aggregate, aggregate enrichment ratio（ER） and other indexes by taking the topsoil in a sloping farmland in the typical black soil zone as the study object. Results showed that the splash erosion amount and net transport amount for cylindrical collectors （upslope, downslope） from different collecting regions exhibited an significant correlation in exponential function with splash distance, and Rz values ranged from 0. 834 4 to 0. 991 1. Aggregate enrichment ratios of the soil changed between 0.00 and 1.79, and the critical particle size fraction of enrichment and depletion for splash erosion was 1.0 mm. Fraction of water stable aggregate in the splashed fragment shows that the proportion of small size fraction increased with increasing splash distance in horizontal space, and 2-5 mm aggregates appeared only in 0-5 cm on upslope and 0-10 cm on downslope, 1-2 mm aggregates mostly distributed on upslope with a largest distributional distance of only 28 cm. MWD values ranged from 0.32 mm to 0.80 mm and declined with increasing splash distance, and MWD in 10-17 cm on downslope was significant different from that in 0-10 cm and 17-40 cm. The study could provide references for further systematic study on the occurrence regularity of black soil erosion and soil loss control.

关 键 词：典型黑土 溅蚀 团聚体 分选 空间分布 

分 类 号：S155.27[农业科学—土壤学] S157.1[农业科学—农业基础科学]