基于遥感的青岛市生态质量时空变化

Temporal and spatial changes of ecological quality in Qingdao city based on remote sensing

海岸带城市资源丰富、经济社会活动剧烈。探讨其生态质量时空变化格局与分布规律,有利于促进海岸带城市的生态环境保护与治理。以青岛市2005、2009、2014和2019年遥感影像为基础数据,通过提取绿度(NDVI)、湿度(WET)、干度(NDBSI)和热度(LST)等指标,构建青岛市遥感生态指数(Remote sensing based ecological index,RSEI)模型,研究分析青岛市生态质量时空变化特征。结果表明:青岛市4年遥感生态指数I均值分别为0.433、0.468、0.470和0.578,生态质量总体呈上升趋势;生态质量空间上呈现郊区优于中心城区的特点,等级以良好和中等等级为主,生态环境改善和恶化的面积分别占总面积的64.43%和1.87%;RSEI模型与各分量指标的平均相关系数为0.803,均高于各分量指标间的平均相关系数。其中对青岛市生态质量影响最大的指标是湿度和绿度,其次是干度,最小的是热度。RSEI模型能较好地反映各分量指标信息,准确表征青岛市水土保持生态修复环境质量状况的变化。

[Background]A good ecological environment is not only the most important premise of human development,but also the basic guarantee of human survival and the basis of social development.Coastal cities are rich in resources and have intense economic and social activities.Exploring the temporal and spatial change pattern and distribution law of their ecological quality is conducive to promoting the ecological environment protection and governance of coastal cities.[Methods]We extracted greenness(normalized difference vegetation index,NDVI),humidity(wetness,WET),dryness(normalized difference build and soil index,NDBSI)and heat(land surface temperature,LST)indexes from remote sensing images of Qingdao in 2005,2009,2014 and 2019,and constructed a remote sensing ecological index of Qingdao remote sensing based ecological index(RSEI)model.Further,we studied the temporal and spatial variation characteristics of ecological quality.[Results]The average I of Qingdao city in 2005,2009,2014 and 2019 were 0.433,0.468,0.470 and 0.578,respectively,and the overall ecological environment quality showed an upward trend.The proportions of areas with excellent ecological environment quality increased from 5.82%in 2005 to 6.14%in 2009,15.93%in 2014 and 42.26%in 2019,respectively.The proportions of areas with poor ecological environment quality decreased from 39.1%in 2005 to 22.73%in 2009,4.18%in 2014 and 1.79%in 2019 respectively.The ecological environment quality of Qingdao city was better in suburb than in central city.The eco-environmental grade was mainly medium and good.The deterioration of ecological environment quality was concentrated in the northern and western coastal areas of Jiaozhou city.The areas with improved eco-environmental quality were mainly distributed in Jimo city,the north of Laixi city and Pingdu city.The improvement and deterioration of ecological environment quality accounted for 64.43%and 1.87%of the total area.The average correlation coefficient between RSEI model and each component index were 0.803,which were higher than the average correlation coefficient between each component index.Among them,WET and NDVI had the greatest impact on the ecological quality of Qingdao city,followed by NDBSI,and LST has the least impact.[Conclusions]The RSEI model can better reflect the information of each component index,accurately characterize the changes of environmental quality of soil and water conservation ecological restoration in Qingdao city,which provide reference and guidance for the ecological restoration,treatment and development of coastal zone in Qingdao city.