The factor that does not affect a habitat's carrying capacity is the genetic variation in the population. Carrying capacity is the largest number of individuals of a population that a given environment can support. I don't think genetic variation would affect the carrying capacity, however, it is important for the adaptation of organisms in an environment. When a population has reached a carrying capacity then it means, the population growth is zero, the rate at which resources are used is equal to the rate at which they are supplied and the birth rate is equal to death rates.