Loess, the soil found in the Yellow and Yangtze River valleys, was very  as well as fertile, but it was also highly prone to -Select-.

Loess soil, which is characterized by its fine, silt-sized particles, is indeed very fertile and has played a crucial role in agriculture, particularly in the Yellow and Yangtze River valleys of China. However, it is also highly prone to erosion. Due to its structure, loess can be easily washed or blown away by water and wind, which can lead to significant loss of topsoil. This erosion can affect agricultural productivity and the stability of the land in these regions. The phenomenon is exacerbated in areas where vegetation cover is sparse, and human activities such as farming can further disturb the soil, making it more vulnerable to erosion. Therefore, while loess is valuable for its fertility, managing its erosion is vital for sustainable land use.