the more people there are the more trees are needed to make homes and build fires and also more food is needed to feed the population
it decreases the population
Immigration, emigration, death rate, and birthrate
The short answer is that population growth restricts the forest in at least two ways: more people need more land to live on, and they need more lumber to build with.
Factors such as food supply, climate, predators, disease all affect the ability of organisms to survive and reproduce.