In ecology, any event, such as fire, flood, or earthquake, that disrupts the everyday running of an ecosystem. A disturbance regime is marked by short, but recurring episodes of high magnitude, or at critical sites. Disturbance-related landforms tend to be polygenetic and heterogeneous, and are long-term/permanent adjustments to fires, volcanoes, etc. Church (2002) Freshw. Biol. 47, 4 argues for a disturbance-related interpretation of mountain rivers.