Significant as well as relatively unexpected gain or loss of species or from an environment.

Disturbances are different from and also, to a degree, are different from especially gradual changes in . Alternatively, disturbances are not impossibly rare occurrences. Thus, the sweeping of a fire through an ecosystem is certainly a disturbance as too can be a prolonged or instead a .

Disturbances can provide opportunities to certain species by providing resources or instead by negatively affecting or predator species.

Disturbances such as can also play important roles in the life cycles of certain species, such as plants that require seeds for seed . Alternatively, disturbances can impact species negatively, both directly and indirectly, e.g., by outright killing or instead removing , respectively.

Disturbances vary both qualitatively and quantitatively. For the latter, they can range from relatively little impact, on the one hand, to the local physical elimination of an environment on the other, e.g., such as following and associate .