Question 1:A

Question 2:B

Question 3: D.

Question 1: The sediment concentration of the Yellow River ranks first in the world. The theme revealed in the cartoon is that the Yangtze River basin has been seriously damaged in recent years, and soil erosion has led to a great increase in sediment concentration. If it is not further treated, it may become the second Yellow River. Therefore, the same ecological problem in the Yangtze River and Yellow River basins is serious soil erosion. So choose option a in this question.

Question 2: In recent decades, due to deforestation and steep slope reclamation in the middle and upper reaches of the Yangtze River, the vegetation coverage rate has been greatly reduced, and reclamation around lakes has seriously damaged the ecological environment and caused serious soil erosion, resulting in a significant increase in sediment concentration. So this question chooses option B.

Problem 3: The "overground river" is formed in the lower reaches of the Yellow River, and the riverbed is higher than the ground outside the dike, so it is difficult to inject the river to form tributaries, so there are few tributaries in the lower reaches of the Yellow River, resulting in a small basin area. So choose option d in this question.

Location of test center: this topic examines the flood control and development and utilization of the Yangtze River; Comprehensive utilization and control measures of the yellow river.