Erosion affects the environment by stripping away top soil on agricultural land, damaging delicate coastal areas, causing health problems in humans and contaminating bodies of water with sediment that can harm plant and animal life. Erosion damages farm land by removing nutrient-rich soil needed to grow plants and by exposing lower-quality soil. It also damages crops and causes greater runoff of needed water.
Beaches erode when the sand lost can't keep pace with sand added through natural processes. The construction of dams has significantly decreased the supply of sand constantly being transported to beaches by rivers and streams, while natural erosion of beaches by wind and water continues.
Degradation of soil by erosion makes it hard and compact, and it lessens the ability of soil to hold water. This decreases oxygen available for plants to grow. Wind is more able to move soil with no plants to hold it down. Soil particles in the air can affect human and animal health when they are inhaled. The particles accumulate in the lungs and cause chronic respiratory problems. Blowing dust also increases the risk of car accidents due to lowered visibility.
Sediment that is deposited in bodies of water by erosion makes it difficult for light to shine through the water, harming the growth of plants. Excessive nutrients in the sediment promote algae growth and deplete oxygen that animals and plants need.