广州市生态系统服务价值空间异质性变化

基于广州市2004―2016年土地利用分类成果，通过CA-Markov模型模拟预测2020年土地利用状况，结合格网分析法构建广州市2004―2020年的生态系统服务价值（Ecosystem Services Value，ESV）密度格网，并展开Getis-Ord热点区分析和圈层分析评估，分析广州市快速城市化进程土地利用变化对ESV变化过程和影响的空间异质性。结果表明：1）广州市快速城市化进程中，建设用地扩张占用了大量生态用地，建设用地面积从2004年的1 320 km2扩张到2016年约2 000 km2，预计2020年将达到2 263.63 km2，生态用地斑块日趋破碎化；2）2004―2016年间，广州市ESV总值累计减少了92.41亿元，年均减少约8.4亿元，预计2016―2020年其继续减少但减速会放缓；3）ESV高值区域的格网数量净减少近18%，低值区域的格网数量净增加约46%，局部区域生态系统服务功能的改善难以抵消快速城市化造成的ESV损失；4）广州市ESV变化呈现局部空间自相关现象，高冷区常年集聚分布在花都区和番禺―南沙一带，高热区从集聚分布于东北部逐渐变成为零星分布；5）ESV圈层格局从中心城区向外围区（核心区、近郊区、边缘区和外围区）呈“低―低―中―高”向“低―低―低―高”的结构特征演变，地处城市边缘的近郊区域和边缘区域逐渐形成空间异质性最突出的城乡交错带。

Spatial Heterogeneity Change of Guangzhou Ecosystem Services Value

The ecosystem maintains the material cycle, biodiversity and ecological balance on earth by providing a variety of services and benefits, which constitutes the environmental basis for human survival and development. The phenomenon that the elements and their ecological processes in the ecosystem distributes unevenly and complexly in spatial series is called "Spatial Heterogeneity", which is one of the most significant special feature for ecosystem. Ecosystem Services Value (ESV) is an important index for quantitative ecosystem services evaluation. Maintenance and conservation of ecosystem services functions is the natural environment foundation for achieving sustainable city development, but also the only way for the new urbanization. Guangzhou(GZ) will continue to be in the stage of rapid urbanization, the pressure on the coordination between the social economy and the natural ecological environment will continue to increase, the potential ecological risk and the imbalance of the ecological service function caused by the urbanization process deserve to be paid attention. Using the 2004-2016 land use classification results that acquire in supervised classification from Landsat TM/OLI images, this paper simulated the 2020 land use map by CA-Markov and built up ESV density grid of study area between 2004 and 2020 with ESV equivalent factor. A study of ESV evolvement rule of Spatial Heterogeneity in GZ with a series of spatial analysis like Getis-Ord Hot-Area Analysis and Ring Structure Analysis was conducted. The result shows that: during the study period in 2004-2020, 1) construction land in GZ has increase from 1320km2 in 2004 to about 2000km2 in2016, and estimate that it will be increase to 2 263.63 km2 in 2020, with the rapid urbanization process in over more than a recent decade, the expansion of construction land has occupied plenty of ecological land, urban built-up area of GZ has gradually developed to an urban patch with enormous area, ecological land patches has become more and more fragment; 2) the sum value of ESV have been net reduced by 9.241 billion RMB between 2004 and 2016, annually net reduced 840 million RMB, the next few years will continue to be reduced but the reduction will slow down; 3) high ESV grids have net decreased 229,about 18%,low ESV grids have net increased 218, about 46%, although ESV increase in some part of area because of ecological environment construction, it is difficult to neutralize the ESV loss caused by the rapid urbanization process; 4) the ESV decreased grids concentrated in the areas of urban expansion such as Huadu and Panyu-Nansha territory, most of the ESV rose grids located in Conghua and Zengcheng, and we predicted that a large number of ESV decreased grids will appear in Nansha; 5) the ESV evolution presents the spatial agglomeration characteristics of high and low values, the high cold grids distributed in the Huadu and Panyu-Nansha, and the high heat grids gradually become sporadic distribution from the concentration distribution in Northeast region; 6) ESV structural feature of pattern circle evolve from "low-low-medium-high" to "low-low-low-high", suburbs area and marginal area that located in urban fringe and gradually shaped the urban-rural ecotone with most prominent Spatial Heterogeneity.