Spatial–Temporal Changes in the Distribution of Populus euphratica Oliv. Forests in the Tarim Basin and Analysis of Influencing Factors from 1990 to 2020

Abstract

Understanding the spatiotemporal evolution patterns of Populus euphratica Oliv. (P. euphratica) forests in the Tarim Basin (TB) and their influencing factors is crucial for regional ecological security and high-quality development. However, there is currently a lack of large-area, long-term systematic monitoring. This study utilized multi-source medium and high-resolution remote sensing images from the Landsat series and Sentinel-2, applying a Random Forest classification model to obtain distribution data of P. euphratica forests and shrublands in 14 areas of the TB from 1990 to 2020. We analyzed the effects of river distance, water transfer, and farmland on their distribution. Results indicated that both P. euphratica forests and shrublands decreased during the first 20 years and increased during the last 10 years. Within 1.5 km of river water transfer zones, P. euphratica forests more frequently converted to shrublands, while both forests and shrublands showed recovery in low-frequency water transfer areas. Farmland encroachment was most significant beyond 3 km from rivers. To effectively protect P. euphratica forests, we recommend intermittent low-frequency water transfers within 3 km of rivers and stricter management of agricultural expansion beyond 3 km. These measures will help maintain a balanced ecosystem and promote the long-term sustainability of P. euphratica forests.