摘要
以三峡库区消落带主要土类紫色土和优势草种狗牙根为研究对象,通过开展无根系土壤对照(CK)、未经除草剂处理的活根试样(LR)和经除草剂处理的死根试样(DR)三种处理土壤的崩解试验,分析了狗牙草根系影响紫色土崩解性能的作用机理。结果表明:狗牙根根系的存在能够有效减少土壤崩解量并降低其崩解速率,狗牙根活根和死根根系分别降低崩解量的50%以上和33%左右;根系的这一作用机理又可分为物理作用和化学作用两个方面,而物理作用占根系总作用的51.36%~61.57%,即根系减少土壤崩解量的作用以物理作用为主。随着坡度增加,根系减少崩解量的物理作用呈现先增加后减小、化学作用则呈持续增加的趋势变化。本研究结果对深入理解植物根系对土壤崩解性能的影响具有重要意义。
The main soil type(Purple soil)and the dominant species(Cynodondactylon)from the water-level fluctuation zone in the Three Gorges Reservoir were selected in this study.The aims were to evaluate the physical and chemical effects by plant roots on soil disintegration.Three modes of experimental conditions,including the sample without root as control(CK),the sample with live root not treated by pesticide(LR)and the sample with dead root treated by pesticide(DR),were established to investigate different sample disintegration processes under different slopes with homemade disintegrating device.The results showed that root effectively reduced the cultivate soil disintegration amounts and rates.Live and dead root of the Cynodondactylon reduced the disintegration amounts by over 50%and about one third,respectively.The physical effect by the root accounts for 51.36%to 61.57%of total effects by root system,which suggested that the plant root system can effectively reduce the occurrence of soil disintegration,and physical effect of plant plays a major role in the reduction of disintegration.When slope gradient increased,it was regularly shown that the reduction in disintegration due to physical effect by root increased initially and decreased afterwards,due to chemical effect by root increased continuously.This result is of great significance for understanding the effects of plant roots on soil disintegration.
作者
肖海
彭逗逗
邵艳艳
洪焕
杨悦舒
李铭怡
夏振尧
许文年
XIAO Hai;PENG Dou-dou;SHAO Yan-yan;HONG Huan;YANG Yue-shu;LI Ming-yi;XIA Zhen-yao;XU Wen-nian(Key Laboratory of Geological Hazards on Three Gorges Reservoir Area(China Three Gorges University),Ministry of Education,Yichang 443002,China;Engineering Research Center of Eco-environment in Three Gorges Reservoir Region,Ministry of Education,Yichang 443002,China;College of Biological and Pharmaceutical Sciences,China Three Gorges University,Yichang 443002,China)
出处
《土壤通报》
CAS
CSCD
北大核心
2019年第5期1116-1122,共7页
Chinese Journal of Soil Science
基金
国家重点研发计划项目课题（2017YFC0504902）
国家自然基金青年科学基金项目（41807068）
长江科学院开放研究基金（CKWV2018488/KY）
三峡库区地质灾害教育部重点实验室开放基金（2017KDZ10,2018KDZ06）资助
关键词
植物根系
土壤崩解
紫色土
消落带
Root
Soil disintegration
Purple soil
Water-level fluctuation zone
作者简介
肖海(1988-),男,博士,讲师。主要研究方向:土壤侵蚀机理。E-mail:oceanshawctgu@163.com;通讯作者:夏振尧,E-mail:xzy_yc@126.com。
