高山草甸生态系统修复单元划定研究——以达日县为例

Study on Delimitation of Restoration Unit of Alpine Meadow Ecosystem:Take Dari County as an Example

受高海拔和高原气候的影响,高寒草甸极易发生退化,且草地生态系统对水源涵养、土壤保持、防风固沙、生物多样性等生态系统服务功能有重要影响,在保障区域生态安全格局和响应全球气候变化等方面发挥着重要的作用。达日县具有典型的高寒草甸生态系统,本研究基于达日2015-2020年草地生态监测数据、遥感影像数据、大气监测数据、土壤监测等数据,运用遥感解译、空间分析、水量平衡方程、土壤流失方程、修成风蚀方程、INVEST模型等方法,分析草地退化,评价草地生态系统服务功能,划分主导生态功能分区,对生态修复单元划定进行研究,结果显示,(1)达日生态主导功能以水源涵养和生物多样性及土壤保持为主;(2)中重度退化草地近草地总面积的40%;(3)共划分7个生态修复单元:夏曲流域草地退化修复单元、昂苍曲流域草地退化修复单元、吉迈河流域草地退化修复单元、黄河沿岸草地退化修复单元、达日河流域综合修复单元、柯曲流域综合修复单元、尼曲流域草地退化修复单元。研究结果将为高寒草甸退化地区生态修复提供方向。

Affected by high altitude and plateau climate,alpine meadow is prone to degradation,and grassland ecosystem has an important impact on ecosystem service functions such as water conservation,soil conservation,wind prevention and sand fixation,biodiversity,and plays an important role in ensuring regional ecological security pattern and responding to global climate change.Dari County has a typical alpine meadow ecosystem.Based on dari2015-2020 grassland monitoring data,remote sensing image data,atmospheric monitoring data,soil monitoring and other data,this study uses remote sensing interpretation,spatial analysis,water balance equation,soil loss equation,modified wind erosion equation,invest model and other methods to evaluate the service function of grassland ecosystem,measure the degree of grassland degradation and divide the leading ecological function zoning to study the delimitation of ecological restoration units.The results showed that,(1) the main ecological functions of dari were water conservation,biodiversity and soil conservation;(2) moderate and severe degraded grassland accounts for 40% of the total grassland area;(3) it is divided into seven ecological restoration units:Xiaqu watershed grassland degradation restoration unit,Cangangqu watershed grassland degradation restoration unit,Jimai River watershed grassland degradation restoration unit,Yellow River coastal grassland degradation restoration unit,Dari River watershed comprehensive restoration unit,Kequ watershed comprehensive restoration unit and Niqu watershed grassland degradation restoration unit.The results will provide direction for ecological restoration in alpine meadow degraded areas.