Habitat loss is a term used to describe the destruction or degradation of ecosystems. When a habitat is destroyed, the species that depend on it are often forced to move or go extinct. Synonyms for habitat loss include deforestation, land-use change, urbanization, fragmentation, degradation, and destruction. Deforestation refers specifically to the loss of forests, while land-use change encompasses any conversion of natural land to agricultural or urban uses. Urbanization is the process of cities expanding into formerly rural areas, while fragmentation describes the breaking up of large habitats into smaller, isolated patches. Degradation refers to the decline in quality of a habitat due to pollution or other factors, and destruction refers to complete loss of a habitat.