The growths of many populations decrease as the density increases. The greater the density becomes, the more vigorously the limiting factors slows down population growth and then gradually the density approaches the carrying capacity of the environment. Another aspect that is important to population is density - independent limiting factors. The factor limiting the growth of a population is not related to population density. For example, temperature and oxygen supply are often related to physical aspects of the environment.
Temperature frequently limits the size of the insect population.
Throughout the summer the population size grows rapidly but in the fall, population size declines rapidly as adults die, thus the population declined before it reached the carrying capacity. Population density is closely related to the spread of certain diseases. For example, Malaria is a density - dependent factor because the denser the human population, the greater the chance of the disease being passed to others. The spread of Malaria is also dependent on the density of the mosquito population. In a dense population, disease can spread rapidly and kill many organisms in a matter of days.