Yep. The thing that keeps any particular form of life in check are predators. A large amount of plant growth promotes herbivore populations, which promotes carnivore populations. If carnivores or herbivores overeat, they crash their own food supply, causing their own population to decline due to food scarcity. Ecosystems reach a form of homeostasis this way.

Humans have eliminated anything even close to being their predator at any significant scale, except our own behaviour. As a result, we run the risk of exhausting our own food (read: resource) supply.