Add Mulch to the Dirt But did you know that mulch also helps keep the dirt moist longer? This makes it harder for the fresh dirt to wash away, slowing the natural evaporation of the moisture that happens. Because of this, erosion is slowed as well. This entire process helps prevent the water from washing the dirt away.

After a heavy rainfall, soil starts to spread out; soil structure is lost. Erosion depletes nutrient supplies or macronutrients like nitrogen, potassium, calcium, magnesium, and sulfur. This changes the soil content, soil texture at the surface, water-holding capacity, and pH levels.

Soil is also greatly affected by rainfall. If it is too wet or too dry, nutrients in the soil can run off and not make it to the plants’ roots, leading to poor growth and overall health. Additionally, as mentioned previously, overwatering or too much rain can also lead to bacteria, fungus, and mold growth in the soil.

1.1 Rainwater infiltration and run-off When it rains, water falling to the surface of the soil will either infiltrate into the soil or run off along the surface. Part of the water that infiltrates into the soil will be absorbed by the upper soil layers and part will seep down into the deeper soil layers.

Rainfall, and the surface runoff which may result from rainfall, produces four main types of soil erosion: splash erosion, sheet erosion, rill erosion, and gully erosion. If the soil is saturated, or if the rainfall rate is greater than the rate at which water can infiltrate into the soil, surface runoff occurs.

Nutrient Mining From the Soil This is especially true if you plant the same type of crop in a plot each year rather than rotating crops. Unless the nutrients are replenished in the soil, it will become infertile. Without a food source, such as crop residues, these organisms may die out, further reducing soil fertility.