Pioneer plants become established on the bare mineral substrate from spores, seeds, or other propagules that are blown, washed, or caried in by animals. Examples of Primary Succession See page 856, text Primary succession on bare rock. Volcanic eruption is primary succession. Following the eruption, there is no life in the blast zone. Eventually, however, pioneer species of plants do establish themselves, beginning the course of succession.
Primary succession can also occur from man-made structures.
Secondary succession is the reconstruction of an ecosystem following a disturbance that damages or removes all or part of the existing community, BUT leaves the soil intact. Secondary succession, as with primary succession, tends to result in the transition of a community from the original pioneer species to climax community. Because soil is already present, the rate of secondary succession is much faster than primary succession. Pioneer species become established from propagules surviving in the soil or from vegetation in surrounding undisturbed areas. Floods , tornadoes , and fires are all examples of naturally occurring disturbances .