摘要
高寒高海拔矿山经过多年开采后生态系统破坏严重,生态修复困难重重,本文以地处青藏高原东南缘海拔高于4300 m的西藏某铜矿为例,探讨高海拔矿产开发工程人工建植和自然草皮移植生态修复效应。结果表明:1)高寒草甸矿区排土场采取生态修复后,人工建植草地草本层平均高度增加,植物盖度下降,植物丰富度指数、多样性指数和均匀度指数均降低,与天然植被相比,人工建植植被群落出现自我更新现象,移植自然草皮植被群落出现退化现象。2)高寒矿区天然草地土壤有机质、全氮、有效磷和速效钾含量较高,矿区生态修复后土壤中各养分含量指标下降。与天然草地相比,人工建植草地土壤有机质、全氮、有效磷和速效钾含量分别下降39.67%、31.56%、67.83%和14.40%,自然草皮移植草地土壤中各指标分别下降72.30%、72.29%、61.62%和6.77%。3)天然草地土壤为中性,矿区土壤重建生态修复后土壤呈碱性,人工建植草地和自然草皮移植草地土壤pH分别增加15.71%和11.43%。4)与天然草地相比,自然草皮移植草地土壤重金属汞(Hg)、砷(As)、铅(Pb)、锌(Zn)和镍(Ni)含量均显著增加,而人工建植草地各重金属元素含量没有显著变化,表明草皮移植生态修复措施,加大了土壤重金属元素污染的风险。
After years of mining,the local ecosystem in the alpine region on the plateau is seriously damaged,and restoring it to its original state is difficult.This paper focuses on the ecological restoration effect of the mineral resources development project,taking a copper mine in Xizang with an altitude of over 4300 m located in the southeast margin of the Qinghai-Tibet Plateau as an example.The results showed that:1)after the ecological restoration of planting grass in the alpine meadow mining area,the average height of the herbaceous layer increased,and the plant coverage decreased,accompanied by the decline of richness index,community diversity index,and evenness index.Compared with the local natural vegetation,selfrenewal of vegetation communities appeared in planted grasslands,and degradation of vegetation communities appeared in natural turf-transplanted grassland.2)The contents of soil organic matter,total nitrogen,available phosphorus,and available potassium in natural grassland of alpine mining areas were high,but the soil nutrient contents decreased after ecological restoration.Compared with natural grassland,the soil organic matter,total nitrogen,available phosphorus,and available potassium of artificial planting grassland decreased by 39.67%,31.56%,67.83%,and 14.40%,respectively,and the natural turf transplantation indexes decreased by 72.30%,72.29%,61.62%,and 6.77%,respectively.3)Natural grassland soil was neutral,and the soil was alkaline after ecological restoration in the mining area.The soil pH of artificial planting grassland and natural turf-transplanted grassland increased by 15.71%and 11.43%,respectively.4)Compared with the local natural vegetation,the content of heavy metals Hg,As,Pb,Zn,and Ni in the natural turf-transplantation grassland soil increased significantly,while the content of each heavy metal element in artificial grassland did not show significant changes.Our results indicate that the ecological restoration measures of turf transplantation have increased the risk of soil heavy metal
作者
南维鸽
焦磊
王浩
胡光印
肖锋军
董治宝
张欣
NAN Weige;JIAO Lei;WANG Hao;HU Guangyin;XIAO Fengjun;DONG Zhibao;ZHANG Xin(Department of Geographical Sciences,Shaanxi Normal University,Xi’an 710062,Shaanxi,China)
出处
《草业科学》
CAS
CSCD
北大核心
2023年第12期3018-3029,共12页
Pratacultural Science
基金
第二次青藏高原综合科学考察研究项目(2019QZKK0403)。
关键词
青藏高原
矿产开发
生态修复
土壤重建
植被群落
土壤理化性质
重金属元素
Qinghai-Tibet Plateau
mineral development
ecological restoration
soil reconstruction
vegetation community
soil physical and chemical properties
heavy metal elements
