Abstract: To delve into the impact of water and sediment variations on basin ecological restoration and sustainable economic development, we scrutinized the variations of precipitation, runoff, and sediment transport within the Yangxin River Basin in the upper reaches of Ganjiang River from 1964 to 2020 by using a variety of methods. Such methods include the Mann-Kendall nonparametric trend test, Pettitt test, Spearman rank correlation coefficient method, and cumulated slope change rate comparative method. We aimed to pinpoint the primary factors influencing sediment transport alterations. Our findings indicate the following: (1) Annual rainfall and runoff in the Yangxin River Basin remained relatively stable from 1964 to 2020, contrasting with a notable upward trend in annual sediment transport. (2) Precipitation, runoff, and sediment transport exhibit seasonal disparities, predominantly occurring in flood season (March-June). (3) While annual rainfall and runoff remained steady, a significant shift in annual sediment transport occurred in 1995 (P<0.01). (4) Rainfall and human activities contributed -0.35% and 100.35%, respectively, to the rise in sediment transport. Human activities such as rare earth mining, navel orange cultivation, and cross-river highway construction emerged as key drivers of water loss and soil erosion in the Yangxin River Basin. This research holds paramount importance for guiding the adjustments in planting strategies and promoting environmentally friendly mineral resource utilization within river basins.

Key words: water and sediment variation, climate change, human activities, contribution rate, Yangxin River basin