(2) An ecosystem, usually always natural, being in a state of equilibrium means that their key biotic and abiotic features of large ecosystems like the major biomes (but not small ecosystems like a rotting log) remain stable and are relatively constant over a period of time. Succession is the gradual process of usually predictable (establishing and replacing type) changes in the composition of a biotic community (plants, animals, fungi, microorganisms) and the abiotic conditions following a natural or human-caused disturbance so that an ecosystem can recover and restore its equilibrium. Which succession occurs slower and less often? *(A) Primary succession occurs on newly exposed ground such as sand or bare rock following a geological event like volcanic eruptions, landslides, or avalanches.(B) Secondary succession occurs in a partially disturbed AQUATIC ecosystem in which a community is disrupted but not destroyed such as previously vegetated soil following a natural disaster or human-caused activities like industrial pollution from surface mining (https://www.britannica.com/video/182701/succession-life-environment-ship-coral-reef-process).(C) Secondary succession occurs in a partially disturbed TERRESTRIAL ecosystem in which a community is disrupted but not destroyed such as previously vegetated soil following a natural forest fire or human-caused activities (https://www.britannica.com/video/153023/process-succession-disturbance).
