以长株潭城市群核心区为对象,运用GIS和RS技术获取研究区土地利用/覆盖和空气污染分布格局,结合景观指数移动窗口分析结果,分年均和季节时间尺度分析NO2、PM10、O3、PM2.5浓度空间分布特征与土地利用格局的耦合关系。结果表明:长株潭城市群土地利用/覆盖,对空气污染物浓度的变化影响显著,具有季节效应。建设用地和道路面积占比与NO2、PM2.5浓度显著正相关,与O3浓度呈显著负相关;林地面积占比越大,NO2、PM2.5浓度越低;土地利用/覆盖对PM10浓度影响相对不稳定,易受不同季节局地尺度工业生产和建筑开发活动影响。从土地利用/覆盖微观配置角度,景观破碎程度越高,PM10浓度越高;散布与并列指数越大,NO2和PM2.5浓度越高、O3浓度越低;多样性指数与PM2.5浓度显著正相关。从优化土地利用降低空气污染角度创建的长株潭城市群生态绿心区的作用尚未真正展现。研究结果对明确反映土地利用/覆盖与空气污染特征间的关系,指导城市土地利用活动的合理开发具有重要的价值。
Land use/cover changes generally have complex effects on air pollution situations. Taking Chang-Zhu- Tan urban agglomeration as an example, this study investigated how do the air pollution concentrations vary with the land use/cover changes. In this process, the land use/cover was firstly retrieved from Landsat 8 images and was consequently used to calculate and map the landscape metrics. Meanwhile, concentration surfaces of PM25, PM10, NO2, and O3 in January, May, August and October were generated separately with the observed data from 23 stationary sites. After that, Pearson correlation coefficient was utilized to measure the relationships between concentration surfaces and land use/cover, as well as its landscape metrics. Results reveal that the highest average NO2 concentration occurred in the built-up and road areas, while the green spaces generally had lower concentrations. This situation was almost repeated by PM25 concentration all through the year except in spring, but was completely opposite to that of 03. However, impacts of land use/cover on PM,o concentration are relatively undeterminable due to the locally intensive industrial activities and building constructions. Analysis of landscape metrics further demonstrates that the increased index values of Perimeter-Area Fractal Dimension (PAFRAC) and Shannon Diversity (SHDI) were basically accompanied with higher PM10 and PM25 concentra- tions, respectively. Interspersion and Juxtaposition Index (IJI) were positively correlated with the concentrations of PM10, NO2, and PM25, however it was found negatively correlated with 03 concentration. In addition, findings from the "Ecological Green Heart" demonstration district suggest that the optimization of land use/cover pattern contributed only slightly to the decline of air pollution concentrations in this area. Therefore, it can be concluded that the air pollution concentrations in Chang-Zhu-Tan urban agglomeration were certainly influenced by its land use/cover pattem, and rational land use d