This study looked at how rainfall affects runoff in different types of land in Shanxi Province. They found that rainfall intensity is the main factor influencing surface flow. Land with good water and soil conservation had less runoff, while areas like farmland and stock breeding had more runoff when it rained heavily. Soil and water loss was severe in agricultural areas. When it rained over 20 mm, areas without forests had less initial water absorption than forested areas. Smaller watersheds also absorbed water faster than larger ones.