近30年来滇中城市群生态用地变化轨迹时空演变特征及其驱动机制

Spatial-temporal Characteristics and Driving Mechanism of Ecological Land ChangeTrajectories in Central Yunnan Urban Agglomeration in Recent 30 Years

[目的]生态用地在维持生态平衡和支撑经济发展方面发挥着重要作用。研究滇中城市群生态用地的时空演变特征和驱动机制对优化生态安全格局、推进云南生态文明建设、筑牢国家西南生态安全屏障具有重要现实意义。[方法]利用Google Earth Engine(GEE)云平台对滇中城市群1990—2020年生态用地进行识别的基础上,采用变化轨迹分析、热点分析和地理探测器对滇中城市群生态用地时空变化轨迹和驱动机制进行了探索。[结果](1)滇中城市群生态用地变化以非生态用地与林地互换为主,并集中发生在林地和非生态用地的过渡地带,而生态用地内部之间(林地和草地)的转换主要发生在研究区北部和南部的山地区域。(2)生态用地变化以低频次变化为主,高频次较少,频次变化在元江干热河谷、金沙江干热河谷区域、滇东滇东南喀斯特地带表现出明显的聚集效应。(3)耕地面积变化是影响滇中城市群生态用地变化的主要驱动力,社会经济因素对生态用地的影响力显著高于自然因素,在自然环境、耕地扩张、生态修复政策等多重驱动下,多因子交互作用对生态用地变化更具解释力。[结论]滇中城市群生态用地破碎,自然环境的改变和人类活动的日益增强极易导致生态用地发生变化,亟需分区域合理制定生态保护措施,筑牢国家西南生态安全屏障。

[Objective]Ecological land plays an important role in maintaining ecological balance and supporting economic development.It is of great practical significance to study the spatio-temporal evolution characteristics and driving mechanism of ecological land use in central Yunnan urban agglomeration to optimize the ecological security pattern,promote the construction of ecological civilization in Yunnan,and build a strong ecological security barrier in southwest China.[Methods]Based on the identification of ecological land use in the central Yunnan urban agglomeration from 1990 to 2020 by Google Earth Engine(GEE)cloud platform,the spatial and temporal change trajectory and driving mechanism of ecological land use in the central Yunnan urban agglomeration were explored by using change trajectory analysis,hot spot analysis and geographic detector.[Results](1)The change of ecological land in the central Yunnan urban agglomeration mainly occurred in the transition zone between non-ecological land and forest land,and the change between ecological land(forest land and grassland)mainly occurred in the mountainous area in the north and south of the study area.(2)The changes of ecological land use are mainly less of high frequency and low frequency,and the frequency changes show obvious aggregation effect in the hot and dry valley of Yuanjiang River,the hot and dry valley of Jinsha River and the karst zone of East and southeast Yunnan;(3)The influence of social and economic factors on ecological land use is significantly higher than that of natural factors.Driven by natural environment,cultivated land expansion and ecological restoration policies,the interaction of multiple factors has more explanatory power on ecological land use change.[Conclusion]The ecological land in the urban agglomeration of central Yunnan Province is broken,the change of natural environment and the increasing human activities can easily lead to the change of ecological land,and it is urgent to formulate reasonable ecological protection measures by region to build a strong ecological security barrier in southwest China.