基于RSEI的徐州市区转型期生态环境质量时空演变分析

Spatiotemporal evolution analysis of urban ecological environment quality in Xuzhou city during transition period based on RSEI

【目的】探寻徐州市区转型期生态环境质量的时空演变规律,为生态保护和相关政策的制定提供依据。【方法】利用2000—2020年5期Landsat数据,构建遥感生态指数(Remote sensing ecological index, RSEI),基于皮尔逊相关性系数、空间自相关等方法分析徐州市区生态环境质量时空演变特征,使用地理探测器探测影响生态环境质量的主要因子。【结果】(1)2000—2020年研究区RSEI值在0.5~0.6范围内波动,生态环境质量不稳定;低等级生态环境质量,主要分布在云龙区、泉山区和鼓楼区,高等级生态环境质量主要分布在铜山区和贾汪区;(2)2000—2020年生态环境质量改善的面积占比35.70%,恶化的面积占比23.23%,生态环境质量与其变化情况呈显著负相关。RSEI等级越高,生态环境质量越容易恶化,等级越低越容易改善;(3)生态环境质量具有明显空间聚类特征,高-高聚类区域分布在铜山区,低-低聚类区主要分布在云龙区、泉山区、鼓楼区及贾汪区,20年来高-高聚类区标准差椭圆方向性明显,始终呈现“西北—东南”向分布格局,低-低聚类区标准差椭圆呈现“西南—东北”向分布格局;(4)地理探测器探测结果显示,所有影响因子结果均显著,主导因子为绿度,双因子交互作用明显。【结论】徐州市区转型后生态环境质量有所改善,生态治理取得一定成效。

[Objective]The present paper aimed to explore the spatiotemporal evolution of the ecological environment quality in Xuzhou urban area during the transition period,and to provide a basis for ecological protection and related policy formulation.[Method]Using five-period Landsat data from 2000 to 2020,the Remote Sensing Ecological Index(RSEI)was constructed,and the spatiotemporal characteristics of the ecological environment quality in Xuzhou urban area were analyzed based on Pearson correlation coefficient,spatial autocorrelation and other methods.The geodetector was used to detect the main factors affecting the ecological environment quality.[Result](i)The RSEI value of the study area fluctuated between 0.5 and 0.6 from 2000 to 2020,indicating that the ecological environment quality was unstable;the low-grade ecological environment quality was mainly distributed in Yunlong district,Quanshan district and Gulou district,while the high-grade ecological environment quality was mainly distributed in Tongshan district and Jiawang district;(i)The area proportion of the improved ecological environment quality from 2000 to 2020 was 35.70%,while the area proportion of the deteriorated ecological environment quality was 23.23%.There was a significant negative correlation between the ecological environment quality and its change,and the higher the RSEI grade,the easier it was to deteriorate,and the lower the RSEI grade,the easier it was to improve;(ii)The ecological environment quality had obvious spatial clustering characteristics,and the high-high clustering area was distributed in Tongshan district,while the low-low clustering area was mainly distributed in Yunlong district,Quanshan district,Gulou district and Jiawang district.In the past 20 years,the standard deviation ellipse of the high-high clustering area showed obvious directionality,and always presented a‘northwest-southeast'distribution patern,while the standard deviation ellipse of the low-low clustering area presented a southwest-northeast distribution pattern;(iv)The geodetector results showed that all the influencing factors were significant,and the dominant factor was greenness,and the interaction effect of the two fac-tors was obvious.[Conclusion]The ecological environment quality of Xuzhou urban area improves after the transition,and the ecological governance achieves some results.