[Ecological Environment Quality Monitoring of Qitai Oasis Based on Land Use/Cover Change and Remote Sensing Ecological Index].

Abstract

Based on Landsat remote sensing images, this study conducted a quantitative assessment of the spatiotemporal alterations in the ecological environment quality at the Qitai Oasis in Xinjiang, situated at the northern foothills of the Tianshan Mountains, triggered by human activities. This assessment was conducted through a combination of the remote sensing ecological index （RSEI） and land use/cover change （LUCC）. In addition, we used spatial autocorrelation analysis and geographic detector to examine the spatial distribution characteristics and its influencing factors of RSEI. The results demonstrated that： ① The average RSEI values for Qitai Oasis in four different years （2001, 2007, 2014, and 2022） were 0.392, 0.423, 0.452, and 0.438, respectively, indicating a lower overall level of ecological environment quality in the area. The spatial distribution highlighted a poor level in the northern and southern regions, with the central area displaying noticeably better quality. The temporal trend showed an initial growth followed by a subsequent decline, with an overall tendency toward an increase. ② The ecological environment quality in the Qitai Oasis exhibited positive spatial autocorrelation, with low-low clustering primarily concentrated in the northern part of the oasis, closer to the Gurbantünggüt Desert. Further, the high-high clustering was featured by an aggregation from scattered distribution towards the central agricultural areas of the oasis. ③ Natural factors had a negligible influence on the spatial distribution of RSEI in Qitai Oasis, and the primary catalyst for RSEI changes was LUCC. ④ RSEI aptly portrayed the present condition of the ecological environment quality in the Qitai Oasis. Changes in RSEI of natural ecosystems, such as RSEI of grassland and bare land, provided significant cues, illustrating the variations in the ecological environment quality of arid regions.