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...

DNA carries genes coding for proteins
Genetic Information and Protein Synthesis

Genes are expressed through the process of protein synthesis. This elaborate tutorial provides an in-depth review of the..

Freshwater aquatic plankton
Freshwater Communities & Plankton

Planktons are microscopic organisms that live suspended in aquatic habitats. There are two groups: the phytoplanktons an..

Human Nervous System
The Human Nervous System

The nervous system is essentially a biological information highway. This tutorial gives an overview of the nervous syste..

An artist's depiction of the origin of amphibians
Amphibians & Early Reptiles

Obtaining air outside an aquatic environment required species to acquire suitable adaptations, and this was the case of ..

Ploidy
Polyploidy

Humans are diploid creatures. This means that for every chromosome in the body, there is another one to match it. Howeve..

Muscle
Muscle

Muscle cells are specialized to generate force and movement. Learn about the different types of muscle tissues in this t..

Related Articles...

No related articles found

See all Related Topics