122 / 2023-06-11 19:54:01

Comprehensive evaluation of ecological environment quality in Ganluo County based on remote sensing and GIS

ecological environmental quality; comprehensive assessment; mean-variance approach; Ganluo

Ecological environment is the basis and condition for human survival. Ecological environment quality assessment can reveal the law of ecosystem change, and the results are of great significance for ecological environment protection and restoration. Based on Landsat5 and Landsat8 remote sensing images of Ganluo County in Sichuan Province in 2009 and 2018, six ecological factors including normalized vegetation index (NDVI), slope, aspect, land surface temperature(LST), land use and humidity index were selected as evaluation indexes. The mean square deviation method was used to determine the weight of each evaluation index, the comprehensive index evaluation model was established,the ecological environmental quality index of the study area was calculated, the ecological environmental quality of Ganluo county was comprehensively evaluated, the grade distribution map of ecological environmental quality was drawn by GIS software, and the spatial distribution law of ecological environmental quality of Ganluo County was revealed. The results showed that: (1) From 2009 to 2018, the mean value of eco-environmental quality index increased from 52.54 to 53.06, indicating that eco-environmental quality had a trend of improvement. The coefficient of variation decreased from 0.20 to 0.17, indicating that the gap of ecological environment quality in Ganluo County was narrowing. (2) From the perspective of spatial distribution, the regions with poor eco-environmental quality in Ganluo County mainly concentrated in the central region, while the eastern and southern regions had better eco-environmental quality. The areas with excellent, good and poor eco-environmental quality decreased significantly, while the area in the middle region increased greatly from 1088.07km² to 1177.54km². (3) From the perspective of dynamic change of eco-environmental quality, the areas with improved eco-environmental quality were mainly concentrated in the central part of Ganluo County, and the areas with deteriorated eco-environmental quality were mainly distributed in the northeast and west parts of Ganluo County, while the areas with unchanged eco-environmental quality were basically unchanged in the southern part of Ganluo County. Among them, the area with unchanged eco-environmental quality accounted for the largest proportion, accounting for 73.32%. From the perspective of ecological environment protection, this paper analyzes the current situation of land ecological environment in Ganluo County and the ecological environment problems existing in land renovation, comprehensively strengthens the monitoring of ecological environment quality in the whole county, improves the ecological environment quality in Ganluo County, and promotes the coordinated and sustainable development of economic society and environment in Ganluo County. In the future, the coordinated development of ecological protection in Ganluo County should continue to strengthen the combination of soil and water conservation engineering and ecological landscape engineering, strengthen the ecological management and protection system, and weigh the multi-functionality of the sustainable development of reclaimed land and cultivated land reserve resources.