雅鲁藏布江山南宽谷流域生态安全格局构建

Construction of ecological security pattern in ShannanWide Valley Basin of Yarlung Zangbo River

山南宽谷流域是雅鲁藏布江主要宽谷之一,特殊的地理环境致使该流域既是严重的土地沙化生态脆弱区,也是重要的沿江经济发展带,构建合理的生态安全格局可为未来生态功能提升与经济发展提供依据参考。以山南宽谷流域为研究对象,基于生态系统服务价值和生态敏感性评价,识别出生态源地,利用最小累积阻力值确定了生态安全区并识别生态廊道,构建山南宽谷流域2020年生态安全格局。结果表明:(1)山南宽谷流域生态源地面积为1089.68 km^(2),主要分布于贡嘎县、扎囊县和乃东区内的草场和林区。(2)在山南宽谷流域内建立了高、较高、中等、较低、低水平生态安全区,分别占流域总面积的24.74%、51.24%、10.31%、5.43%、8.28%,不同生态安全区应采取不同的措施以保证生态环境的安全。(3)识别出总长4720.08 km的105条生态廊道,与生态源地、生源点和生态安全区共同构成山南宽谷流域生态安全格局。(4)结合土地利用现状建议山南宽谷流域南岸进行适度产业开发,北岸以生态保护为主,并提出构建“一地一场两区四园”的发展格局。

Shannan Wide Valley Basin is one of the prime valleys of the Yarlung Zangbo River of China.The geographical environment of the basin makes it vulnerable to land desertification and ecological degradation,while also making it an important belt of economic development along the river.Ecological security patterns can provide a reference for future improvements in ecological functions and economic development.Based on the evaluation of ecosystem services and ecological sensitivity,the ecological source areas were identified.The minimum cumulative resistance value was used to determine ecological security zones and ecological corridors,and the ecological security pattern of the Shannan Wide Valley Basin was constructed for 2020.The results showed that:(1)The ecological source area of the basin was found to be 1089.68 km2,with distribution mainly occurring in grassland and forest areas of Gonggar County,Zhanang County,and Nedong District.(2)Zones of maximum,high,medium,low,and minimum ecological security were established,accounting for 24.74%,51.24%,10.31%,5.43%,and 8.28%of the total basin area,respectively.To ensure ecological security,different measures should be applied at each level of the ecological security zone.(3)The constructed ecological security pattern comprised 105 ecological corridors with a total length of 4720.08 km,together with various ecological source areas,ecological source points,and ecological security areas.(4)In addition to the current land use situation in Shannan Wide Valley,moderate industrial development should take place on the southern banks of the river,while ecological protection measures should be the focus for the northern banks.Further,the“one land,one field,two districts,and four parks”development pattern should be followed.