Influence of Nano-carbon Composite Layer on Soil Water Infiltration and Water Distribution
XUE Wenqiang;ZHOU Beibei;MAO Tong;CHEN Xiaopeng;WANG Quanjiu;State Key Laboratory Base of Eco-hydraulic Engineering in Arid Area,Xi'an University of Technology;State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau,Institute of Soil and Water Conservation,Chinese Academy of Science and Ministry of Water Resources;
The effects of nano-carbon on soil water infiltration,soil water characteristic curve and soil water distribution were studied by TDR and tensiometer through one dimensional vertical soil column test.The results showed that:(1)With the increasing of infiltration time,the cumulative infiltration amount of the soil contained nano-carbon decreased in the same infiltration time,and the advancing distance of wetting front decreased obviously,and the application of nano-carbon presented obvious infiltration reduction effect.Using Philip infiltration model to fit infiltration data,the infiltration rate S decreased with the increasing of nano-carbon content,meanwhile with the increasing of nano-carbon content,the cumulative infiltration amount decreased gradually in the early stage of water infiltration.The linear fitting of wetting front in different layers showed that infiltration rate decreased significantly when wetting front entered second layers of soil,and nano-carbon layer had obvious effect of water blocking.(2)Adding nano-carbon,the water content of nano-carbon composite layer increased obviously,and soil water content in the lower layer of the nano-carbon composite layer was lower than that in the blank control group.When the nano-carbon content was 0.5%,the soil water content of the nano-carbon composite layer was the maximum.(3)Adding nano-carbon could significantly improve the water holding capacity of soil when the soil was under dehydration condition;the soil water characteristic curves were fitted using the van Genuchten model,and the soil water retention rate(θr),saturated water content(θs)and the correlation coefficient(α)of the formula significantly increased compared with the soil without nano-carbon,andthe shape coefficient nwas smaller than that of the soil without nano-carbon.
【Fund】： 国家自然科学基金项目(51239009 41371239);; 陕西省科技支撑项目(2013KJXX-38);; 陕西省自然科学基金项目(2015JQ5161);; 西安理工大学特色研究计划项目(2016TS013)
【CateGory Index】： S152.7
【CateGory Index】： S152.7