Answer: Primary succession: Glaciers, bare rock, lichen
Secondary succession: Wildfires, volcanoes, hurricanes, deforestation
Explanation:
Succession in ecology can be defined as gradual changes that occur in the biotic community in an ecosystem with respect to the changes that occur in the abiotic components of the environment. Primary succession initiate in an land which is not previously occupied by any living species. These includes the changes that occur at the primitive level on the land. That is the formation of glacier from the ice, bare rock will undergo withering and disintegration to form the soil, lichen are the biological composite organisms formed by the mutual association of algae and fungi. These lichens act upon the rocks to cause its withering by releasing the chemicals causing disintegration of the rocks.
Secondary succession occurs at those regions which have been colonized by the living species and get disturbed due to human oriented or natural disasters. Wildfires can be set up naturally, through volcanic eruption, or can be human induced can clear up the forests but some remains of seeds and deep rooted roots can help in growth of new plants which will again initiate the succession, again volcanoes, and hurricanes, are also natural hazards which can affect the population of species in an ecosystem. Deforestation is a human oriented practice in which vegetation cover or forests are clear cut. This will also cause loss of biodiversity.
