Impact of Land Use/Land Cover Change on Ecological Quality during Urbanization in the Lower Yellow River Basin: A Case Study of Jinan City

Rapid urbanization in the lower Yellow River basin has greatly contributed to the socio-economic development of Northern China, but it has also exacerbated land use/land cover change, with significant impacts on ecology. Ecological quality is a comprehensive spatial and temporal measure of an ecosystem’s elements, structure and function, reflecting the ecological state under external pressures. However, how land use/land cover change affects the ecological quality during urbanization has rarely been explored. In this study, Jinan, a megacity in the lower Yellow River basin, was taken as a typical region, and the response of ecological quality to the land use/land cover change in 2000, 2010 and 2020 was retrieved using the remote sensing ecological index. For the mixed land use/land cover change types, a type-decomposition and spatial heterogeneity quantification method based on the abundance index was proposed, and the impact mechanisms of the land use/land cover change on the ecological quality were revealed by coupling with GeoDetector. The results show that: (1) Farmland and built-up areas, as the dominant land use/land cover types, were the primary factors controlling the spatial pattern of ecological quality. (2) Urban expansion and farmland protection policies resulted in the transfer of farmland and woodland to built-up areas as well as the transfer of woodland and grassland to farmland, which intensified the degradation of ecological quality. (3) Ecological protection policies prompted the transfer of farmland and grassland to woodland and the transfer of farmland to grassland as the main cause for the improvement of ecological quality. (4) Although ecological protection and urban development were implemented in parallel, uneven land use/land cover changes resulted in a 1.4 times expanded area of poorer ecological quality with increasingly serious spatial agglomeration effects. This study can provide scientific references for the ecological conservation and high-quality, sustainable development of cities in the lower Yellow River basin.