Practice question

Frequent or intense disturbance repeatedly removes biomass and interrupts population growth. Species that mature slowly, reproduce infrequently, or require stable habitat cannot complete their life cycles, leaving only disturbance-tolerant taxa, rapid colonizers, or organisms with resistant stages. This strong environmental filter reduces richness and often produces communities dominated by a few stress-tolerant forms. Under the intermediate disturbance hypothesis, diversity is therefore low at the high-disturbance end. “Generalist” may describe some survivors, but broad resource use is not the universal mechanism; specialized fire-adapted or flood-adapted species can also persist. The essential point is tolerance and rapid recovery. Specialists do not generally dominate as a category, and resource richness cannot compensate if organisms are removed faster than populations establish. Disturbance frequency must be considered relative to generation time: an annual event may be severe for a long-lived tree but routine for a short-lived microbe. Spatial refuges and recolonization can preserve regional diversity even when local diversity is depressed. The hypothesis contrasts this filtering with low disturbance, where competitive exclusion rather than repeated mortality can reduce coexistence.