基于InVEST和PLUS模型下的土地利用变化及生境质量演变分析:以汉中盆地为例

Analysis of Land Use Change and Habitat Quality Evolution Based on InVEST and PLUS Models:Example from Hanzhong Basin

汉中盆地是中国南水北调工程中的重要源头区,分析区内土地利用及生境质量,能提高对该地区演变规律的认识,进一步保护下游研究区的自然资源和生态环境安全。笔者基于2000~2020年20年内共3期土地利用数据,建立了研究区多类型土地利用数据库和生境质量评估体系,从土地利用转移矩阵、景观格局指数、生境质量等多个方面对研究区内的土地利用的时空变化进行研究,并利用PLUS模型进行土地利用扩张和预测分析。结果表明:2000~2020年,土地利用类型变化较大,变化转移主要发生在水田和农村居民点用地、城镇用地之间;蔓延度指数逐年减少,景观破碎化程度较高;生境质量结果呈逐年下降趋势,高值面积减少并向南部扩展,低值面积增多并以城镇为中心向外辐射扩散,高等级的生态质量景观由水域和林草为主,主要沿汉江流域分布。

Hanzhong Basin is an important source area in China's South-to-North Water Diversion Project.Analyzing land use and habitat quality within the region can enhance our understanding of its evolutionary patterns and further protect the natural resources and ecological environment security of the downstream working areas.This paper establishes a multi-type land use database and a habitat quality assessment system for the working area based on three periods of land use data from 2000 to 2020.It studies the spatiotemporal changes of land use in the research area from multiple aspects including land use transition matrix,landscape pattern indices,and habitat quality,and uses the PLUS model for land use expansion and prediction analysis.The results show that from 2000 to 2020,there were significant changes in land use types,mainly transfers between paddy fields,ru-ral residential land,and urban land.The sprawl index decreased year by year,indicating a high degree of land-scape fragmentation.Habitat quality results showed a downward trend year by year,with the area of high values decreasing and expanding southward,and the area of low values increasing,radiating outward from urban cen-ters.High-grade ecological quality landscapes,dominated by water bodies and forests and grasslands,are main-ly distributed along the Han river basin.