基于多源数据的生态环境质量变化研究——以广州市为例

Research on Eco-environment Quality Variation Based on Multi-source Data:A Case Study of Guangzhou

基于Landsat影像计算遥感生态指数,结合土地覆盖数据分析广州市2000―2020年生态环境质量的时空变化,通过兴趣点(POI)核密度结果评价广州市功能设施分布现状,利用地理探测器研究广州市生态环境质量空间分异的主要影响因素。结果表明:近20年来,广州市生态环境质量优级和中级的面积占比分别上升了10.59%和2.19%,良级面积占比下降了13.16%,良级向中和优级转变的趋势显著,丘陵和山地生态环境质量呈上升趋势,城市扩张区域则有所下降;各因子对归一化差异植被指数(NDVI)、干度指标(NDBSI)和地表温度(LST)的解释力度较高,在人类活动强度较高的低海拔不透水面地区,NDVI与缨帽变换的湿度分量(Wet)偏低,NDBSI与LST偏高,对生态环境具有负效应,广州北部的丘陵山地NDVI较高,LST较低,对生态环境有利。

The Remote sensing-based Ecological Index was calculated based on Landsat imagery,and the spatio-temporal variation characteristics of the eco-environment quality in Guangzhou from 2000 to 2020 were analyzed in combination with the land cover data set.Kernel density results of Points of Interest (POI)were used to evaluate the distribution status of functional facilities in Guangzhou,and explore the key factors contributing to the spatial differentiation of eco-environment quality using geographic detectors model.The results showed that:in the past 20 years,the area proportion of medium and excellent eco-environment quality grades on the rise were 10.59% and 2.19% respectively,while the area proportion of good eco-environment quality grades decreased by 13.16%.There was a significant trend of transformation from good grades to medium and excellent grades.In hilly and mountainous areas,the eco-environment quality increased,while in urban expansion areas,it decreased.Each factor had a higher explanatory power on normalized difference vegetation index(NDVI),normalized difference built-up and soil index(NDBSI)and land surface temperature(LST).In low-altitude impervious areas with high intensity of human activities,NDVI and wetness component of the tasseled cap transformation(Wet)were low,while NDBSI and LST were high,which had a negative effect on the ecological environment.The hills and mountains in the northern part of the study area had higher NDVI and lower LST,which were beneficial to the ecological environment.