A successional change, usually from an existing climax community, leading to a less diverse and less structurally complex community. The change frequently involves a reduction in biomass. Retrogression is usually triggered by an environmental factor (e.g. a pollutant) and disturbance by humans is often involved, e.g. in removing top predators or tree cover and thereby setting in motion a downward development in ecosystem complexity.
Subjects: Plant Sciences and Forestry — Ecology and Conservation.