Remote Sensing Evaluation of Urban Ecological Changes in Arid Region Oasis: A Case Study in Liangzhou District of Wuwei, China

Abstract

The ecological environment quality of the oasis city in Liangzhou District of Wuwei City in arid region from 2000 to 2016 is evaluated by using RSEI, which integrates four ecological evaluation indicators (greenness, humidity, dryness, and heat). The results show that the ecological index of remote sensing based on principal component analysis can objectively quantify regional ecological changes; the overall ecological environment quality in Liangzhou District of Wuwei is slightly improved, the average RSEI raised from 0.447 to 0.458, and the overall increased 2.46%. Liangzhou District Eco-environmental Quality Grades from Medium to Two Polarized Development. The large-scale cultivation of arable land in the northeastern desert area has improved the ecological environment. The expansion of urban areas and the construction of new areas in the central region have reduced the quality of the ecological environment. The NDSI (Normalized difference soil index) which represents the degree of dryness has the largest contribution to the RSEI, indicating that the decline in the quality of the ecological environment is closely related to the increasing impervious surface.