Abstract: Small wetlands provide many ecological services, such as maintaining biodiversity, regulating hydrology and purifying water quality. However, they are highly sensitive to climate change and human activities. Clarifying the spatiotemporal variations and driving mechanisms of small wetlands can provide data support and theoretical basis for the ecological restoration and protection of small wetlands. Based on remote sensing data and environmental factors from 1994 to 2020, we conducted a comprehensive analysis of landscape pattern changes and driving mechanisms of small wetlands in western Jilin, using dynamic degree models, spatial centroid models, and geographic detectors. The results showed that: (1) The landscape pattern of small wetlands in western Jilin exhibited spatiotemporal heterogeneity, with the geographical center of gravity significantly shifting from west to east. The most severely degraded regions were in an order of Daan City, Taonan City, Zhenlai County, and Taobei District. Between 1994 and 2009, the area of small wetlands decreased by 6839.93 hm². (2) The overall area of small wetlands decreased by 44.98%, with the number of patches reduced by 45.57%. Such reduction was mainly manifested in the connection and merger of small wetlands with large wetlands and their transformation into saline-alkali land and cultivated land. (3) Economic growth, population dynamics, and land use changes were the main driving factors for the transformation of small wetlands, with the cumulative contribution of human activities exceeding 80%. In contrast, natural factors such as vegetation index (NDVI), precipitation, temperature, and potential evapotranspiration (PET) had limited impact. This study provides important scientific evidence for understanding the evolution mechanism of small wetlands and practical implications for the protection and sustainable management of small wetlands in western Jilin and similar regions.

Key words: small wetland, driving factor, geographic detector, landscape pattern, western Jilin