Population
ecology
is a subdiscipline of ecology dealing with the growth and decline of populations.
Why
is population ecology important?
Aside
from the issue of human population size, understanding population growth is important in
conserving species, in controlling and predicting outbreaks of pests and diseases, in
understanding evolution, and in measuring the effects of various environmental factors on
wild species.
Several
factors determine the growth of a population. These
factors are called limiting factors and include examples such as: predation,
parasitism, climate, competition for food, pollution, disease, and availability of water.
How
Populations Grow
v Three
important characteristics of a population are its geographic distribution, density, and
growth rate.
v
Three factors affect population size: the number of births, the number of deaths, and the
number of individuals that enters or leaves the population.
v
Under ideal conditions and with unlimited resources, a population will continue to grow in
a pattern called exponential growth.