Dynamic changes in land use are vital for ecological balance and sustainable development. Based on the case of Naiman Banner in Tongliao City, Inner Mongolia, time-series remote sensing data were examined to monitor changes in land use and conduct spatiotemporal analysis to support the sustainable development of this region. Given the complexities of this agro-pastoral region, the seasonal characteristics of time-series satellite imagery were utilized to produce high-precision land use products. Based on which, this study analyzes the spatiotemporal changes in land use in Naiman Banner over the past 40 years and assesses the ecological impacts of various land use changes. The results indicate differentiated spatiotemporal characteristics in land use, with the northern region exhibiting trends of desertification recovery, urban expansion, and an increase in arable land, while the southern mountainous areas show a trend of returning farmland to grass and forest. Factor contribution analysis reveals that changes in agricultural land use, ecological recovery from desertification, and deceased surface water significantly affect soil moisture content in the area, underscoring the importance of water-saving agriculture, ecological restoration of sandy areas, and water resource protection for sustainable agricultural development. This study provides important data for land resource management in Naiman Banner and offers scientific evidence for sustainable development strategies in this region, facilitating the coordinated advancement of ecological environments and economic development.