Answer: The needs of the living things within the ecosystem.
Explanation: Carrying capacity for an ecosystem means the amount of organisms an ecosystem can carry. If the ecosystem overpopulates with a certain species, it decreases the biodiversity of the entire ecosystem. A main factor that the carrying capacity of an ecosystem is limited by is the needs of the living things in that ecosystem. If that ecosystem overpopulates, every species in that ecosystem will compete to meet the needs of their own, whether it's food, water, or shelter.
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