Disturbances That Reset the Ecosystem

Irregular Fires

Irregular fires are among the most frequently cited disturbances of an ecosystem. Given their potential for massive destruction and their highly visible nature, large fires seldom go unnoticed by man. However, depending on the scope of the fire, the impact on the environment need not be long-lived. Such events may cause death to plants and animals, but they also return resources back to the environment. A sound ecosystem will recycle those resources into new growth and food for animals. As larger plants and animals return, the ecosystem will pick up where it left off.

Severe windstorms share many similarities to fires in the way they affect an ecosystem. High winds can strip foliage, uproot plants, and displace or kill animals. Unlike the effects of fires, however, the damage from a windstorm can take longer to recover. Fallen flora and fauna require additional time and the action of animals, fungi and bacteria to break down. If the damage is not too widespread, however, the ecosystem is reset as the resources are returned through biological action and renewed.

Sudden floods are one of the most variable ecosystem disturbances. A light flood can merely displace animal life with no significant effect on flora, while a major flood can displace or kill a majority of plant and animal life in the region. Under the right circumstances, the level of destruction caused will reset the ecosystem. The accumulation of dead animal and plant matter brought with the floodwater serves to fertilize the system, kick-starting the system into a period of renewal and eventual recovery.

Volcanoes combine many different environmental disturbances at once. Lava flows can initiate all-consuming fires that are extremely distressing to any ecosystem. Acidic ash covers plants and chokes animals, causing harm or destruction to both. Seismic and wind forces from explosive eruptions have destructive consequences similar to those of windstorms. Despite the extreme stresses that volcanic activity place upon an ecosystem, these disturbances still can reset the environmental clock. If sufficient plant and animal populations remain, they will often thrive in the nutrient-rich ash and other residues, causing the populations to recover vigorously.