Which term best describes the process of land loss through nature's actions?

Erosion is the term that best describes the process of land loss caused by natural actions, predominantly involving the movement of soil and rock by wind, water, ice, or gravity. This process can lead to significant changes in the landscape over time, as the forces of nature gradually wear away the earth's surface. For example, riverbanks may recede, coastline areas can diminish due to wave action, and hillsides may erode due to rainfall.

In contrast, accretion refers to the gradual buildup of land caused by sediment deposition, which is the opposite of what is described in the question. Avulsion pertains to a sudden change in land due to natural events, such as a river changing its course, leading to an immediate shift rather than a gradual loss. Reliction describes the process of land emerging due to the receding of a body of water, resulting in the formation of new land rather than the loss of existing land. Each of these terms accurately describes specific phenomena related to land and water interactions, but erosion specifically aligns with the concept of land loss through natural processes.