The study looked at trends in runoff and water levels in the Xiang River basin over the past thirty years. They used a statistical method to analyze the data and found that annual runoff in the middle-lower reaches of the river has been increasing. Summer and autumn runoff is also on the rise due to increased precipitation. Water levels have been steadily increasing as well, likely due to changes in vegetation and sediment in the river channels. Overall, the study provides important information for managing water resources and understanding flood risks in the area.