矿山恢复过程及前期恢复时限分析

目前矿山生态环境防治原则“谁开发谁保护,谁污染谁治理,谁破坏谁恢复”对矿山恢复到特定程度还没有明确的时间要求。矿山恢复可分为前期和后期两个阶段,前期恢复以水土保持为目的,后期恢复以建立稳定的生态系统为目的。草本植被在前期恢复中具有显著的水土保持功效。不同区域的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。据估计,草本植被恢复到70%的盖度,热带林区大致需要5~9个月,亚热带常绿阔叶林带需要9~15个月,温带林区需要15~24个月,寒带针叶林带和温带草原则需要超过两年的时间。建立的盖度-T(时间)-NPP曲线,结合区域植被有效盖度,为矿山前期恢复的时限制定提供依据。

Analysis for process of mine restoration and time limit of its early restoration

The mine ecological environment preventing and controlling principle is "who develops who to protect,who pollutes who to govern,who destroys who to restore",but the mine restoration to the specific degree does not have the explicit time request.The mine restoration may be divided into two stages,the early period and the late period.The early period restoration takes the conservation of water and soil as a goal and late period restoration takes establishment of the stable ecosystem as the goal.The grassland vegetation in the early period restoration has the remarkable conservation of water and soil effect.The grassland vegetation restoration to the specific degree of coverage has the obvious time differentiation in the different regions.The time and districts"NPP(Net Primary Productivity)have negative correlation.It is calculated that in order to get the grassland vegetation restoration to 70% degree of coverage,tropical forest zone needs approximately for 5~9 months,subtropics evergreen broad-leaved forest zone needs approximately for 9~15 months,temperate forest zone region needs for 15~24 months,the frigid zone needle forest zone and temperate grassland zone need more than two years.According to the curve of coverage-T(time)-NPP and the plants effective coverage in districts,it can provide some information of time limit for the mine early period restoration.