中国水土保持科学2017，Vol.15Issue(6)：1-8,8.DOI:10.16843/j.sswc.2017.06.001
季节性冻融对东柳沟流域风沙土分离能力的影响
Effect of seasonal freeze-thaw on the detachment capacity of aeolian sandy soil in Dongliugou watershed
摘要
Abstract
[Background] Soil detachment is the initial phase of soil erosion,and is of great significance to studies in regions that are characterized by seasonal freeze-thaw regimes.However,this process remains unclear because limited research on soil physical properties and soil detachment capacity has been carried out to date under freeze-thaw conditions.Thus,the aims of this study were to determine and compare the effects of slope gradient,flow discharge,moisture content,soil depth and freeze-thaw cycles on soil detachment capacity.[Methods] The soil samples were collected from the 0-20 cm soil layer in an abandoned cropland.It is located in Dalad Banner,Inner Mongolia which is the crisscross region of Hobq Desert and the Loess Plateau.In this study,in order to elucidate the effects of freeze-thaw on aeolian sandy soil detachment capacity,a series of artificial freeze-thaw simulations in combination with flume experiments were conducted by using the orthogonal method.[Results] 1) Slope,flow discharge,moisture,freeze-thaw cycles and soil depth had significant influence on soil detachment capacity (P ＜ 0.05).The sensitivity degree of each factor on aeolian sandy soil detachment capacity was:slope ＞ flow ＞ freeze-thaw cycles ＞ soil moisture content ＞ soil depth,and slope and flow discharge were main affecting factors.2) The aeolian sandy soil detachment capacity was linearly correlated with flow discharge and slope (R2 ＞ 0.94).The critical value of flow discharge and slope affecting aeolian sandy soil detachment capacity was 0.07 L/min and 6 ％,respectively.3) Soil moisture,freeze-thaw cycles and soil thawing depth influenced aeolian sandy soil detachment capacity indirectly by changing soil physical properties.The process,range and degree of freeze-thaw were restricted by soil moisture content and occurrence condition.If soil moisture content was too higher or lower,it would lead to the increase of aeolian sandy soil detachment capacity.When the soil moisture was 6％,the aeolian sandy soil detachment capacity reached the minimum value.Freeze-thaw cycles resulted in the redistribution of soil moisture.The effect of soil depth on soil detachment capacity was basically consistent with soil moisture content,and aeolian sandy soil detachment capacity of middle depth was the smallest.The aeolian sandy soil detachment capacity increased obviously with the number of freeze-thaw cycles increased,but gradually tended to flat trend after 10th cycles.[Conclusions] The above results indicated that seasonal freeze-thaw increased aeolian sandy soil detachment capacity and it will lead to the increase of soil erosion in spring of the seasonal freeze-thaw area.This research results may provide reference for the study of erosion mechanism of seasonal freeze-thaw areas.The effect of freeze-thaw on the soil detachment capacity,however,requires further investigation in regions where this process occurs seasonally.关键词
冻融作用/冻融循环/土壤分离能力/正交试验Key words
freeze-thaw action/freeze-thaw cycles/soil detachment capacity/orthogonal experiment分类
农业科技引用本文复制引用
肖俊波,孙宝洋,马建业,刘晨光,孙艳,王敏,李占斌..季节性冻融对东柳沟流域风沙土分离能力的影响[J].中国水土保持科学,2017,15(6):1-8,8.基金项目
国家自然科学基金重点项目“黄土高原生态建设的生态-水文过程响应机理研究”(41330858) （41330858）
西北农林科技大学大学生创新训练项目“季节性冻融对土壤可蚀性的影响研究”(201610712035) （201610712035）
广西水利科技项目“红水河流域地区马尾松水保林建设及水源涵养功能量化研究”(201214) （201214）
