1995-2020年郑州市区绿地格局演变及驱动力分析

Spatial-temporal Evolution and Driving Force Analysis of Urban Green Space in Zhengzhou from 1995 to 2020

基于1995-2020年Landsat遥感数据,以郑州市区为研究区域,采用最大似然监督分类与目视解译相结合的方法分析郑州市区1995-2020年绿地面积与景观指数的时空演变特征,并分析其驱动力因素.结果表明:(1)从整体演变来看,市区绿地面积呈现“先大幅下降,随后逐步上升,之后波动下降,近期稳定上升”趋势.从年际变化来看,其前期变化幅度大,中期变化较小,后期变化相对稳定.根据预测,2030年表现为面积减小,破碎化程度降低,呈中部向四周扩张的趋势.(2)从扩张方向来看,NW和SE两个方向上绿地分布较多,但NW和SE轴两侧的绿地分布较少;扩张速度的各向异性虽然差别不大,但在SW和NW方向较其他方位略快;扩张强度在SW和NW方向较大.(3)从景观格局看,斑块密度(PD)波动较大,聚集度指数(AI)波动较小,形状指数(LSI)和最大斑块指数(LPI)的波动程度处于AI与PD之间.与所有景观类型对比,发现绿地与整体景观格局的变化趋势不一致.(4)从时间演化看,影响因子作用排序为第三产业>第二产业>人口密度>总人口数>道路铺张长度>建成区面积>人均公共绿地面积>城镇人口数>固定资产投资增速>第一产业>国民生产总值>社会消费品零售总额.

Based on the Landsat remote sensing data from 1995to 2020,taking Zhengzhou City as the research area,a method combining maximum likelihood supervised classification and visual interpretation was used to analyze the temporal and spatial evolution of green area and landscape index in Zhengzhou City from 1995to 2020and their driving factors.The results show that:①From the perspective of the overall evolution,there is a trend of"first sharply decreased,then gradually increased,then fluctuated and decreased,and recently increased steadily".From the perspective of inter-annual changes,the early stage showed a large range of changes,the medium-term changes were small,and the later-stage changes were relatively stable.According to the forecast,in 2030,the area will decrease and the degree of fragmentation will decrease,showing a trend of expansion from the central part to the surrounding areas.②From the perspective of the expansion direction,there are more green spaces in the NW and SE directions,with NW and SE as the axes,and less distribution on both sides of the axis;The other directions are slightly faster;the expansion strength is larger in the SW and NW directions.③From the perspective of landscape pattern,the patch density(PD)fluctuated greatly,the aggregation index(AI)fluctuated less,and the fluctuation degree of shape index(LSI)and maximum plaque index(LPI)was between AI and PD.Compared with all landscape types,it is found that the change trend of green space and the overall landscape pattern is inconsistent.④The degree of influence of each driving factor on the evolution of regional green space is ranked as tertiary industry>secondary industry>population density>total population>road stretched length>built-up area>per capita public green space area>urban population>fixed assets Investment growth rate>primary industry>gross national product>total retail sales of consumer goods.