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...

Sensory systems
Sensory Systems

A sensory system is a part of the nervous system consisting of sensory receptors that receive stimuli from the internal ..

3D rendering of an antibody
Passive and Active Types of Immunity

Lymphocytes are a type of white blood cell capable of producing a specific immune response to unique antigens. In thi..

Electromagnetic spectrum of a brain
Sleep and Dreams – Neurology

While learning and intelligence are associated with the functions of a conscious mind, sleep and dreams are activities o..

Community Patterns

Learn about community patterns and the ecological factors influencing these patterns. Revisit some of the ecosystems you..

Biosecurity and Biocontrol
Biosecurity and Biocontrol

This lesson explores the impact of biosecurity threats, and why they need to be identified and managed. Examples to incl..

Plant meristem
Plant Meristems and Growth

In plants, growth occurs in meristems, which are the site of repeated cell division of unspecialized cells. These cells ..

Related Articles...

No related articles found

See all Related Topics