Spatial and Temporal Change of Habitat Quality of Poyang Lake Basin in China at Small Watershed Scale and Its Multidimensional Response to Landscape Pattern

The health and function of ecosystems are largely determined by the quality of habitat, and the optimal regulation of landscape patterns has become an important way to improve regional habitat quality. This article takes the Poyang Lake Basin of China as a case, reveals the spatial and temporal change of its habitat quality at the small watershed scale, and attempts to examine the multidimensional response of habitat quality to landscape pattern changes with respect to landscape compositions and landscape configuration. The results show: 1) from 2000 to 2020, the overall landscape fragmentation of the basin decreased, the landscape aggregation in the central small watersheds changed significantly, and the spatial distribution of landscape elements in the central and southern small watersheds were relatively homogeneous. 2) The overall habitat quality of the Poyang Lake Basin is at a middle to high level, with significant spatial differentiation, showing the distribution characteristics of 'high in the periphery, low in the center, high in the south and low in the north'. 3) Both landscape compositions and landscape configurations influenced habitat quality, but there were obvious differences in the response degree. From the landscape composition and configuration dimension, the influence of landscape composition on habitat quality was greater than that of landscape configuration; from the multilevel landscape configuration dimension, compared to landscape level, landscape configuration at the class level impacted habitat quality more deeply. To the end, this article proposes a differentiated regulation strategy for habitat quality conservation in small watersheds from the perspective of landscape patterns to improve the ecological service level of Poyang Lake Basin.