How do dust and sediment from degraded land increase air and water pollution?

Desertification exacerbates environmental degradation by facilitating the movement of dust and sediment, which significantly impairs air and water quality.

Air Pollution

In degraded dryland environments, the loss of vegetation leaves soil exposed to wind erosion. Fine particles, such as silt and clay, can be transported over vast distances, contributing to high levels of suspended particulate matter, including PM${}_{2.5}$. This dust cover is a major factor in air pollution, particularly in regions near deserts where seasonal winds drive these particles into the atmosphere.12

Water Pollution

When land is degraded, soil is easily displaced by surface runoff and carried into waterways as sediment. This process causes several ecological issues:13
* Ecological Disruption: Suspended sediment blocks sunlight penetration, impairs the dissolved-oxygen balance, and disrupts the reproductive cycles of fish and other aquatic life.43
* Physical Damage: Settled sediment smothers bottom-dwelling organisms and fills vital infrastructure like irrigation canals, reservoirs, and stream channels.43
* Increased Costs: Sedimentation necessitates expensive water clarification processes and reduces the overall quality and utility of water resources.54