How have deforestation and overgrazing increased erosion in the Yangtze River basin?

In the Yangtze River basin, deforestation and overgrazing have significantly accelerated environmental degradation and soil erosion.

The clearing of extensive forests in central and southern China for farmland has removed vital vegetation cover, leading to the erosion of hillside soils and their subsequent deposition in valleys. Furthermore, the overcutting of trees and overgrazing in the middle and upper basins have destroyed grass cover, breaking down the soil's crumb structure and reducing its porosity. Without this protective cover, topsoil is easily washed away by heavy rains during the rainy season.12

These practices have had severe consequences for the river system:
* Increased Siltation: The loss of soil has increased the silt load in the river, which contributes to the buildup of sediment on the river bottom.32
* Reduced Flood Capacity: Deforestation has diminished the landscape's ability to absorb and manage intense rainfall, resulting in increased runoff.3
* Flood Risk: The combination of silt-laden rivers and reduced natural flood-control capacity—exacerbated by the conversion of lakes and wetlands into cropland—has made the basin more susceptible to catastrophic flooding.32

Are you interested in learning more about how these environmental changes have influenced specific flood control projects like the Three Gorges Dam?