In ecology, allogenic succession is mediated by the abiotic components of the ecosystem, while the autogenic succession refers to the succession, which is mediated by the biotic components of an ecosystem.
A volcanic eruption wiping out an entire island is an example of allogenic succession.
A soybean crop helping in nitrogen fixation, leading to the development of other species is an illustration of autogenic succession.
A tsunami devastating all the living organism in a habitat is an example of allogenic succession.
Oak trees preventing the growth of smaller sun-seeking shrubs is an example of autogenic succession.