Final answer:
Ecological succession is the process in which a community changes through time. Primary succession occurs in an area that has never before been colonized, while secondary succession occurs in a formerly inhabited area that was disturbed.
Step-by-step explanation:
Ecological succession is the process in which a community changes through time. Primary succession occurs in an area that has never before been colonized, such as newly exposed or formed land. Secondary succession occurs in a formerly inhabited area that was disturbed, such as after a fire or flood.
In primary succession, pioneer species, such as lichens and hearty plants, colonize the area with few soil requirements. Over time, these pioneer species break down the substrate, contribute to soil formation, and make way for other, less hardy species. Secondary succession occurs in areas with nutrient-rich soil, and the process involves the gradual return of the ecosystem to its natural state.