高速公路边坡植物群落的水土保持效应

营造何种植物群落进行高速公路边坡生态恢复,以达到保水固土、维持边坡稳定已成为高速公路边坡生态恢复亟待解决的问题。在思小高速公路边坡进行的生态恢复试验结果表明:林冠层、灌草层、枯枝落叶层均有保水固土和维持坡面稳定的作用,且乔木、灌木和草本植物在整个植物群落中均有不可替代的作用。草本植物早期生长快,对防止初期的土壤侵蚀、减少水土流失效果好;豆科灌木植物具有固氮作用,改良土壤效果好,乡土灌木适应性强,能促进群落顺向演替;乔木可防风固沙、保持水土、维持边坡的稳固,对边坡生态恢复的作用明显。乔灌草群落保持水土的能力要强于灌草群落和草本植物群落,故在高速公路边坡的生态恢复中,应营造合理的乔灌草植物群落。

Soil and Water Conservation Effect of Plant Community on Freeway Slopes

To plant which plant community for ecological rehabilitation of freeway slopes and achieve the purposes of water conservation,soil stabilization and slope stability have become a issue that urgently need to be solved.The outcomes of ecological rehabilitation tested on Sixiao Freeway slopes show that all the crown cover,bush grass cover and withered branches and fallen leaves cover have the function of water conservation,soil stabilization and slope stability,in addition to irreplaceable function of trees,bushes and herbs in the whole plant community.Herbs grow fast in the early days and have good effects on soil erosion prevention at initial stage and soil and water loss reduction;leguminous bushes have notable functions of nitrogen fixation,improving soil,strong adaptability for local ones and promoting direct succession of community and;trees can protect against the wind and dune fixing,keep soil and water,stabilize slopes and have remarkable function of ecological rehabilitation of slopes.The capability of soil and water conservation of arbor,bush and grass community is stronger than that of bush-grass community and herbs community.Therefore,it should plant rational plant community of arbor,shrub and grass during the ecological rehabilitation of freeway slopes.