摘要
利用梯级法、DEM和模型法研究三峡库区传统锄耕条件下的耕作侵蚀速率,同时采用双环法测定未进行耕作扰动区、耕作侵蚀区和堆积区土壤入渗特性的变异。结果表明,本研究区坡度为12.63%的线性坡的单次耕作侵蚀速率为25.02 t/hm2;各小区的土壤入渗速率和入渗时间均可以用Kostiakov公式(f=a·t-b)进行很好的拟合,然而耕作侵蚀区、耕作堆积区和未扰动区之间由于土壤紧实度和耕层深度变化而对土壤水分的入渗特性具有非常显著的影响。相对于耕作堆积区,耕作侵蚀区的土壤初始入渗速率、稳定入渗速率和累计入渗量均具显著减低,因而会显著地加强水蚀作用。与此同时,单纯耕作松土导致的土壤紧实度变小被证明能够显著增强土壤入渗能力,因而能够显著地增加入渗量,从而减少水蚀强度。
Tillage erosion rates under conventional hoeing tillage on the linear slope were assessed using the digital elevation model（DEM）,trapezoid-step method and tillage erosion model.And the field double-ring method was used to examine soil infiltration on a purple soil of the uncultivated plot,tillage erosive region and accumulative region.The results showed that mean soil flux rates due to tillage erosion which obtained by DEM and trapezoid-step method was 25.02 t/hm2 on the linear slope.Meanwhile,the process of infiltration in the uncultivated land,tillage erosive region and accumulative region could be well described with the equation of Kostiakov（f=a·t-b）.Since soil compaction and depth of tillage layer has significant difference between the tillage erosive region and accumulative region,there were significant differences in the process of infiltration between two regions.Compared to the accumulative region,there is a significant reduction of initial infiltration rate,steady infiltration rate,and cumulative infiltration in the tillage erosive region,resulting in more serious water erosion.Meanwhile,tillage operation which decreases soil compaction will increase water infiltration and reduce water erosion.
出处
《水土保持学报》
CSCD
北大核心
2010年第3期194-198,共5页
Journal of Soil and Water Conservation
基金
中国科学院山地灾害与地表过程重点实验室开放研究基金
国家自然科学基金(40771027)
关键词
耕作侵蚀
耕层深度
土壤紧实度
入渗
坡耕地
tillage erosion
depth of tillage layer
soil compaction
infiltration
sloping farmland
