Once a crater, it is now a sunken plain, very large in size. After the eruption of the volcano, the whole region formed a closed internal cycle, the ecosystem is self-contained, although basically isolated from the outside world, but self-sufficient, ecological balance, here animal food is sufficient, no migration is required.
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Once a crater, it is now a sunken plain, very large in size. After the eruption of the volcano, the whole region formed a closed internal cycle, the ecosystem is self-contained, although basically isolated from the outside world, but self-sufficient, ecological balance, here animal food is sufficient, no migration is required.