Chapter 26 - The impact of geomorphological hazards (i.e., mass movements/landslides) on soil erosion

Abstract

Geomorphological hazards, such as landslides, have a significant impact on soil erosion. Landslides are characterized as a gravitational downslope movement of soil and rocks that can be triggered by different factors including heavy rainfall, snowmelt, earthquakes, volcanic activity, and human activities. Similarly, erosion is the process of removal of soil, rock, or sediment from the Earth's surface by natural agents such as water, wind, ice, and gravity, occurring occur in different forms, including sheet erosion, rill erosion, gully erosion, and coastal erosion. Both processes are closely related, once landslides can be responsible for the transport of large amounts of soil and rocks (i.e., shallow landslides and debris flow), contributing to the increase of erosion rates and sedimentation on stream channels, resulting in negative impacts on water quality and aquatic ecosystems. Furthermore, sedimentation can alter the physical and chemical properties of the water, affecting nutrient availability, pH, and other important factors. In the same way, by removing vegetation that helps stabilize slopes, and exposing bare soils, erosion can increase even more the risk of landslides. Although landslides and erosion are natural processes that shape our landscapes, they can present risks to human society and ecosystems. Thus, understanding the causes and impacts of landslides and erosion can help to implement appropriate management practices aiming to mitigate those risks and promote sustainable land use.