长株潭城市群绿心区植被覆盖时空变化特征分析

Characterisation of Spatial and Temporal Changes in Vegetation Cover in the Green Heart of Changzhutan Urban Agglomeration

植被覆盖度(FVC)是衡量地表植被状况的一个重要指标,是描述生态系统的重要基础数据,也是区域生态系统环境变化的重要指示;研究城市植被覆盖变化,可以为城市生态系统建设的可持续发展提供依据。利用Landsat系列数据,运用像元二分法对2000-2022年长株潭城市群生态绿心地区遥感影像的近红外和红光波段进行植被覆盖时空变化特征分析。结果表明:从时间变化上看,22 a绿心区植被覆盖度呈波段增长趋势,不同时间节点上发生植被覆盖度降低变化是由于生产建设活动所造成的。从长株潭城市群绿心区空间规划所规定的禁止开发区、限制开发区和控制建设区三类不同管控区域上看,高植被覆盖度地区面积占比为:禁止开发区(78.06%)>限制开发区(19.09%)>控制建设区(2.85%),低植被覆盖度地区的面积占比为:控制建设区(40.57%)>禁止开发区(35.28%)>限制开发区(24.15%)。整体而言绿心区植被覆盖明显改善,改善趋势和覆盖变异情况都很稳定,绿心区生态环境呈良性发展趋势,进一步完善规划、健全法规制度、强化监管可有力促进长株潭城市群地区的植被改善,将更好地发挥“绿心区”的生态屏障和生态服务功能。

Vegetation cover(FVC)is an important indicator of the condition of surface vegetation,an important basic data for describing ecosystems,and an important indication of environmental changes in regional ecosystems.Using Landsate series data,the image element dichotomy method was applied to analyse the change of vegetation cover in the near-infrared and red light bands of remote sensing images in the ecological green heart area of Changzhutan Urban Agglomeration from 2000 to 2022.The results show that over the past 20 years,the vegetation cover in the Greenheart has improved significantly,and there is no obvious dfference in the spatial distribution of vegetation cover among Chang,Zhu,and Tan cities,but in terms of the three different types of control areas of prohibited development zones,restricted development zones,and controlled construction zones stipulated in the spatial plan of the Greenheart of Chang-Zhu-Tan urban agglomeration,the vegetation cover in the areas with high vegetation cover and that in the areas with low vegetation cover are different from those in the areas with low vegetation cover.The history of the construction and development of the"Greenheart"shows that further improvement of planning,regulations and systems,and strengthening of supervision can strongly promote the improvement of vegetation cover in the Changzhutan urban agglomeration area,and will give better play to the ecological barrier and ecological service functions of the"Greenheart".