Dictionary > Density dependence

Density dependence

Definition
noun
(population ecology) An effect in which the intensity changes with the increasing population density, e.g. the effects in which the intensity increases with the increasing population density
density-dependent
adj.
(population ecology) Of, pertaining to, characteristic of density dependence
Supplement
In population ecology, density dependence pertains to the effect of the present and/or the past population sizes on the per capita population growth rate.1 Density-dependent processes take place when population growth rates are regulated by population density.2
Density dependence may either be positive or negative. A positive density dependence is one in which the population growth is regulated by an increased population density. An example of a positive density dependence is observed in the population density of Schistosomes. The higher the population density of Schistosomes the higher is the probability of mating pairs and reproduction.3 In contrast, a negative density dependence pertains to a situation wherein the population growth is restricted due to crowding, predators, and competition.
See also:

Reference(s):

1 Sale, P. (2002). Coral reef fishes : dynamics and diversity in a complex ecosystem. Amsterdam: Academic Press. p304.

2 Hixon, M (2009), Density Dependence and Independence, Chichester: John Wiley & Sons Ltd,

3 May, R.M. (1977). “Togetherness among Schistosomes: its effects on the dynamics of the infection”. Elsevier North-Holland, Inc.: 301–343.


You will also like...

Stem
Stems

Stems primarily provide plants structural support. This tutorial includes lectures on the external form of a woody twig ..

Kidneys
Kidneys and Regulation of Water and Inorganic Ions

The kidneys are responsible for the regulation of water and inorganic ions. Read this tutorial to learn about the differ..

Direct and indirect physiologic effects of growth hormone
Animal Growth Hormones

Hormones are produced in the endocrine glands of animals. The pituitary gland and hypothalamus are the most impor..

Growth Patterns
Growth Patterns

This tutorial describes the sigmoid curve, annual plant growth, tree growth, human growth, and insect growth as the grow..

Early Earth
The Origins of Life

This tutorial digs into the past to investigate the origins of life. The section is split into geological periods in the..

Physiological Homeostasis
Physiological Homeostasis

Homeostasis is essential to maintain conditions within the tolerable limits. Otherwise, the body will fail to function p..

Related Articles...

No related articles found

See all Related Topics