Climate change and human activities have significantly altered ecosystem elements and the trade-off/synergy between them. Exploring the spatio-temporal variation characteristics of ecosystem elements,understanding the relationships among these elements,and identifying their key influencing factors are essential for guiding effective ecosystem management and for adapting to future climate change. This study analyzed the spatio-temporal changes of various ecosystem elements in the West Liao River Basin from 1990 to 2020,as well as the evolution of landscape gradients in ecological land,farmland,and sandy land. Correlation analysis and bivariate spatial autocorrelation models were applied to explore the trade-off/synergy between ecological land,farmland,and sandy land. In addition,the factors affecting the trade-off between ecological land,farmland,and sandy land were revealed by using the Geodetector. The results showed that: (1) There was a notable expansion of non-ecological land at the expense of ecological land. Among them,farmland area increased by 10.2%,while water and grassland areas decreased by 25.7% and 5.2%,respectively. The conversion between ecosystems mainly occurred among grassland,water,and farmland. The spatial distribution of farmland landscape gradients in the West Liao River Basin became more pronounced and tended to cluster from the eastern to the southwestern areas. Meanwhile,the sandy land landscape gradients were predominantly concentrated in the central region. Conversely,the ecological land landscape gradients exhibited a gradual dispersion in the central region,accompanied by an increase in fragmentation. (2) A significant trade-off was observed between ecological land use and farmland within the West Liao River Basin. The areas involved in this trade-off initially expanded and then contracted,predominantly located in the central and southern plains,which constituted approximately 46% of the total study area. The area of synergy regions initially decreased and then showed an increase,making up approximately 8% of the study area. Per capita Gross Domestic Product (GDP) and population density were identified as significant factors influencing the trade-off dynamics between ecological land use and farmland. (3) The most pronounced trade-off between ecological land and sandy land were primarily observed in the Horqin Sandy Land and western mountainous regions. Both the trade-off and synergy regions exhibited a long-term,relatively stable trend. The trade-off area constituted roughly 23% of the total study area,while the synergy area made up about 22%. Key factors affecting the trade-off relationship between ecological land use and sandy land included elevation and the rate of urbanization. The findings of this research can offer a scientific foundation for the spatial optimization of river basin ecosystems.