一种量化根系抗侵蚀指标的构建及应用:根系构架抗蚀指数

Construction and application of a new index for quantifying root erosion resistance:Root framework erosion resistance index

在侵蚀环境下,植被地下部根系系统的相互匹配是植被群落持续发挥抗侵蚀作用的关键。本研究尝试引入Amoeba图形法,从根系形态、数量和空间3个维度建立根系构架抗蚀指数(ERI_(rf),%)来量化表征植被群落根系抗侵蚀功效,并分析黄土丘陵区撂荒地、柠条群落和刺槐群落植物根系的生长特征。结果表明:本研究构建的根系构架抗蚀指数的参数包括:根系构架作用系数(α)、根系密度(R_b,kg·m^(-3))、根系构架度(S)、土壤容重(ρ,g·cm^(-3))和水土保持作用系数(φ),表达式为:■;根系构架抗蚀指数能够较好地表征植被群落土壤抗侵蚀能力,且对数函数能较好地拟合土壤抗侵蚀能力与根系构架抗蚀指数之间的关系。期望本研究结果为抗侵蚀植被群落构建与生态建设评估提供科学参考。

The matching of root system is a key factor driving the resistance of plant community to soil erosion.In this study,Amoeba graphical method was used to establish a root framework erosion resistance index(ERIrf,%)from three dimensions of root morphology,quantity and spatial concerns to quantify the effective of root erosion resistance by plant community.We analyzed root growth characteristics of plant community from abandoned land,Caragana korshinskii and Robinia pseudoacacia communities in loess hilly area.The results showed that the parameters of constructing the root framework erosion resistance index included the acting coefficient of root framework(α),root density(Rb,kg·m-3),root framework degree(S),soil bulk density(ρ,g·cm-3),and soil and water conservation coefficient(φ).The equation could be expressed as■.This root framework erosion resistance index well represented the erosion resistance effects of plant root system.Logarithmic function could better fit the relationship between soil erosion resis-tance ability and root framework erosion resistance index.Our findings would provide scientific reference for the construction of anti-erosion vegetation community and assessment of ecological construction.