矿山恢复的过程及前期恢复时限分析

矿山恢复可分为前期和后期两个阶段,前期以水土保持为目标,后期以建立稳定的生态系统为目标。草本植被在前期恢复中具有显著的水土保持功效。不同区域草本植被恢复到特定盖度有明显的时间分异,所需时间与区域NPP(植被净第一性生产力)值呈负相关。根据前人所做工作,建立了盖度—T(时间)—NPP曲线,结合区域植被有效盖度,可为矿山前期恢复的时限制定提供依据。据估计,草本植被恢复到70%的盖度,热带林区大致需要3~5个月,亚热带常绿阔叶林带需要5~10个月,温带林区需要10~18个月,寒带针叶林带和温带草原则需要超过两年的时间。

ANALYSIS OF THE PROCESS OF MINE RESTORATION AND TIME LIMITATION OF ITS EX-PERIOD RESTORATION

The mine restoration involves two stages.The purpose of the ex-period restoration is soil and water conservation,the empress period is to establish a stable ecosystem.Herbage plants have obvious effects on water and soil conservation.Herbage plants in different districts need different time for a particular coverage.The time and NPP(net primary productivity)show negative dependence.Based on research in the past,it is estimated that the coverage of herbage to 70%,for the tropical forest zone,needs 3-5 months,for the subtropical evergreen broad-leaved forest zone,needs 5-10 months,for the temperate forest zone,needs 10-18 months,for the cold temperate coniferous forest zone and temperate grassland,needs over two years.According to the curve of coverage-T(time)-NPP and the effective coverage of plants in the districts,it can give a time limitation for ex-period mine restoration.