文献类型：期刊文献

英文题名：Soil Moisture Dynamics and Effects on Runoff Generation at Small Hillslope Scale

作者：Zhao, Nana[1,2] Yu, Fuliang[1] Li, Chuanzhe[1] Zhang, Lu[3] Liu, Jia[1] Mu, Wenbin[1] Wang, Hao[1]

第一作者：Zhao, Nana;赵娜娜

通信作者：Yu, FL[1]

机构：[1]China Inst Water Resources & Hydropower Res, State Key Lab Simulat & Regulat Water Cycle River, Beijing 100038, Peoples R China;[2]Chinese Acad Forestry, Inst Wetland Res, Beijing 100091, Peoples R China;[3]CSIRO Land & Water, Canberra, ACT 2601, Australia

年份：2015

卷号：20

期号：7

外文期刊名：JOURNAL OF HYDROLOGIC ENGINEERING

收录：;EI(收录号：20152500956097);Scopus(收录号：2-s2.0-84931024870);WOS:【SCI-EXPANDED(收录号:WOS:000356238600001)】；

基金：This work was supported by the Foundation of China Institute of Water Resources and Hydropower Research (1232), the International Science and Technology Cooperation Program of China (Grant No. 2013DFG70990), the General Program of the National Natural Science Foundation of China (Grant No. 51209225), and the Open Research Fund Program of State Key Laboratory of Water Resources and Hydropower Engineering Science (2012B093).

语种：英文

外文关键词：Soil moisture dynamics; Subsurface flow; Response lag time; Slope angle; Crop

摘要：Soil moisture variability has a major impact on runoff generation. In this study, the dynamics and variability of soil moisture at small hillslope transects were analyzed by artificial rainfall simulation experiments in which the influence of crop type and slope angle were considered. Soil moisture variability and dynamics during the rainfall-runoff process were monitored by capacitance sensors (EC-5) with high temporal resolution (1min) and continuously measured after rainfall ceased to investigate soil moisture dynamics and patterns by the method of data visualization. Relationships between soil moisture and runoff (surface and subsurface flow) and response lag times of soil moisture at different slope positions and soil layers were investigated. The dynamics of soil moisture during the entire crop growth stage were also analyzed. Results showed that soil moisture exerted strong influence on runoff generation, but the relationships were strongly affected by crop type. There was an obvious threshold (approximately 30% vol soil moisture content) between soil moisture and runoff coefficients/surface flow for the wheat crops for both slope angles, but the relationship between soil moisture and runoff was more scattered for spring maize. The response of subsurface flow to soil moisture exhibited hysteretic behavior attributable to soil moisture characteristics and a long recession process and was significantly influenced by slope angle. Lag times between soil moisture and the generation of subsurface flow were both controlled by antecedent soil moisture conditions. During wet conditions, differences in soil moisture response time at different soil layers were small, and obvious subsurface flow could be observed. Conversely, there were large differences between the response times (e.g.,the increase in soil moisture for 40-cm depth was close to 0) for rainfall events during dry conditions, and little lateral subsurface flow was observed. Understanding relationships between soil moisture and subsurface flows under different slop angles and vegetation covers will help to improve models that aim to predict the impact of land-use change on runoff and provide useful information for evaluating the effects of soil conservation measures on runoff and sediments in north China.