Analysis of Water-Sand Changes and Influencing Factors in the Ganjiang River Basin from 1958-2019

Understanding historical changes of water and sand characteristics in the Ganjiang River basin and their influencing factors is critical task for ecological construction, water resources management, and human production and life in the basin. We here used Mann-Kendall and sliding t-tests to analyze the annual runoff and annual sand transport in the basin based on data from Ganjiang River hydrological stations from 1958 to 2019. Our results show that: (1) the interannual variation of runoff in the Ganjiang River basin from 1958 to 2019 is significant, alternating between flat, dry, and abundant water conditions, with an abrupt change occurring in 1990 at all stations. (2) The annual sand transport at all stations showed a significant decrease, being most significant at Waizhou and Ji'an stations. Abrupt changes in the amount of sand transported at four upstream stations, Ji'an Station, and Waizhou Station were seen during 2002, 1994, and 1997, respectively. (3) Sand transport in the basin varies with runoff, and the two are highly correlated. Factors such as climate change and human activities can affect water and sand changes in the Ganjiang River basin, which requires a thorough understanding of how climate change may impact ecological protection and the strengthening water resources management.