摘要
为了探索原位植物根系固土效应的非直接估测,以泥沙收集法为参照,引入电阻抗法,分析黄绵土中不同根系密度处理下根系固土总效应、物理固结效应及生物化学效应等参数。结果表明:线性方程可以较好地拟合累积泥沙流失量与土壤电阻抗之间的关系,且产流的前3 min电阻抗均值能够较好地反映根系固土效应;根系物理固结效应是强化抗冲性土体构型的关键,平均为66.5%;随着根系密度的增加,物理固结效应呈显著增加趋势,但与泥沙收集法相比,其数值平均低13.5%。因此,电阻抗法在一定程度上能够非直接性估测根系固土抗侵蚀效应。本研究期望为原位植物根系固土效应估测提供新的技术手段。
[Background]In semi-arid areas,soil erosion is a serious threat to land productivity and sustainability for both natural and human-managed ecosystems.Traditional vegetation techniques are recognized as effectively in reducing soil erosion,whereas the most evident vegetation source that protects soil against erosion is root wedging,which is an important mechanism where roots can bind soil together and tie weak surface soil layers into strong and stable subsurface layers.Plant roots significantly affect soil erosion process of overland flow by physical consolidation(root link and root-soil adhesive)and biochemical functions.[Methods]This study introduced electrical impedence method,with the purpose to evaluate the relative contributions of root link,root-soil adhesive as well as root biochemical functions to soil erosion resistance non-directly.For this purpose,a simulated scouring experiment was conducted on a sandy soil with sand content 36.8%,silt content 51.2%and clay content 12.0%.Three treatments considered were:1)fallow(CK),2)root-penetrated soil and 3)simulated-root-penetrated soil.Each treatment had 4 replicates.Rectangular,undisturbed soil samples(20 cm×10 cm×10 cm)were taken in the fallow and root pans and were conducted with a hydrological flume(2 m×0.10 m).The flume contained an opening at its lower base,equaling the size of metal sampling box,so that the surface of soil sample was at the same level of the flume surface.Space between the sample box and the flume edges was sealed with painter’mastic to prevent edge effects.The slope of the flume bottom could be varied and clear tap water flow was applied at 4.0 L/min rate discharge on a washing flume slope of 15°for 15 min.During the 15 minutes of each experiment,samples of runoff and detached soil were collected in every 1 min in the first 3 min and 2 min in the following time using 10 L buckets for determining sedimentation.Then,this paper analyzed the relative role in creating the soil configuration of soil resistance to erosion quantitatively,
作者
李强
刘国彬
张正
亢福仁
马春艳
赵学庆
蒋晋豫
LI Qiang;LIU Guobin;ZHANG Zheng;KANG Furen;MA Chunyan;ZHAO Xueqing;JIANG Jinyu(Yulin University,Shaanxi Key Laboratory of Ecological Restoration in Shaanbei Mining Area,719000,Yulin,Shaanxi,China;State Key Laboratory of Soil Erosion and Dry-land Farming on the Loess Plateau,Institute of Soil and Water Conservation,CAS,712100,Yangling,Shaanxi,China;Desert Control Research Institute of Shaanxi Province,Yulin,Shaanxi,719000,Yulin,Shaanxi,China)
出处
《中国水土保持科学》
CSCD
北大核心
2020年第1期18-24,共7页
Science of Soil and Water Conservation
基金
国家自然科学基金“水蚀风蚀交错区沙柳根系固土抗侵蚀机理研究”(41661101)
国家自然科学基金“优势植物根系构架对矿区排土场新构土体土壤抗侵蚀的影响机理”(41807521)
黄土高原土壤侵蚀与旱地农业国家重点实验室开放基金“毛乌素沙地沙柳群落枯落物格局形成及抗风蚀机理研究”(A314021402-1801)
陕西省青年科技新星人才支持计划项目(202057)。
关键词
根系
土壤流失量
土壤抗冲性
电阻抗
root
soil loss extent
erosion resistance
electrical impedance
