干旱地区农业研究2018，Vol.36Issue(1)：50-55,6.DOI:10.7606/j.issn.1000-7601.2018.01.07
黄土区大豆和马铃薯田土壤临界剪切力季节动态
Seasonal dynamics of soil critical shear stress in soybean and potato farmlands in the loess plateau
摘要
Abstract
In order to provide reference data for establishing the soil erosion process model in the loess plateau.The research take soybean and potato farmlands in the hilly region of the Loess Plateau as a target.The scouring experiments in a laboratory flume to simulate soil detachment by concentrated flow was conducted under the different condition of six flow shear stress(τ=5.71~17.18 Pa).Based on data of soil detachment capacity and flow shear stress,and combined the famous soil erosion process WEPP model,the seasonal dynamics of soil critical shear stress were discussed for soy-bean and potato farmlands during the crop growing season.Results showed that the seasonal dynamics of soil critical shear stress under soybean and potato farmlands in loess areas increased significantly during the whole growing season(P<0.05).During the growing season,soil critical shear stress for soybean fluctuated over time with a pattern of double peak curve.τcvalues varied from 1.66 Pa to 5.37 Pa,with a mean value of 3.34 Pa.The minimum and maximum values of soil critical shear stress for soybean appeared in the seeding stage and harvesting stage,respectively.Soil critical shear stress for potato displayed similar a pattern of the seasonal variation f.τcvalues varied from 1.06 Pa to 5.26 Pa,with a mean value of 3.12 Pa.The minimum and maximum values of soil critical shear stress for potato occurred in the squaring stage and blooming stage,respectively.Positive relations were detected between soil critical shear stress and soil cohe-sion,bulk density,content of water-stable aggregates,and root weight density.Among them,soil bulk density and root weight density were important factors affecting seasonal dynamic of soil critical shear stress.Seasonal dynamics of soil critical shear stress under soybean and potato farmlands could well be simulated with soil bulk density and root weight density(R2>0.50,NSE>0.50).关键词
黄土区/土壤临界剪切力/季节动态/根系生长Key words
loess areas/soil critical shear stress/seasonal dynamics/root growth分类
农业科技引用本文复制引用
郁耀闯,王长燕..黄土区大豆和马铃薯田土壤临界剪切力季节动态[J].干旱地区农业研究,2018,36(1):50-55,6.基金项目
国家自然科学基金项目(41371497,41171423,41601016) （41371497,41171423,41601016）
陕西省重点实验室项目(2018JS009) （2018JS009）
宝鸡文理学院重点科研项目(ZK2017039,ZK2017040) （ZK2017039,ZK2017040）
