ecological Ecology () is the natural science of the relationships among living organisms and their environment. Ecology considers organisms at the individual, population, community, ecosystem, and biosphere levels. Ecology overlaps with the closely re ...

metacommunity is a set of interacting

communities A community is a Level of analysis, social unit (a group of people) with a shared socially-significant characteristic, such as place (geography), place, set of Norm (social), norms, culture, religion, values, Convention (norm), customs, or Ide ...

which are linked by the dispersal of multiple, potentially interacting species. The term is derived from the field of

community ecology In ecology, a community is a group or association of populations of two or more different species occupying the same geographical area at the same time, also known as a biocoenosis, biotic community, biological community, ecological communit ...

, which is primarily concerned with patterns of species distribution, abundance and interactions. Metacommunity ecology combines the importance of local factors (environmental conditions, competition, predation) and regional factors (dispersal of individuals, immigration, emigration) to explain patterns of species distributions that happen in different spatial scales. There are four theoretical frameworks, or unifying themes, that each detail specific mechanistic processes useful for predicting empirical community patterns. These are the patch dynamics, species sorting,

source–sink dynamics Source–sink dynamics is a theoretical model used by ecologists to describe how variation in habitat quality may affect the population growth or decline of organisms. Since quality is likely to vary among patches of habitat, it is important to co ...

(or mass effect) and neutral model frameworks. Patch dynamics models describe

species composition Relative species abundance is a component of biodiversity and is a measure of how common or rare a species is relative to other species in a defined location or community.Hubbell, S. P. 2001. ''The unified neutral theory of biodiversity and biogeog ...

among multiple, identical patches, such as islands. In this framework, species are able to persist on patches through tradeoffs in colonization ability and competitive ability, where less competitive species can disperse to unoccupied patches faster than they go extinct in others. Species sorting models describe variation in abundance and composition within the metacommunity due to individual species responses to

environmental heterogeneity Homogeneity and heterogeneity are concepts relating to the uniformity of a substance, process or image. A homogeneous feature is uniform in composition or character (i.e., color, shape, size, weight, height, distribution, texture, language, i ...

, such that certain local conditions may favor certain species and not others. Under this perspective, species are able to persist in patches with suitable environmental conditions resulting in a strong correlation between local species composition and the environment. This model represents the classical theories of the niche-centric era of G. Evelyn Hutchinson and Robert MacArthur. Source-sink models describe a framework in which dispersal and environmental heterogeneity interact to determine local and regional abundance and composition. This framework is derived from the

metapopulation A metapopulation consists of a group of spatially separated populations of the same species which interact at some level. The term metapopulation was coined by Richard Levins in 1969 to describe a model of population dynamics of insect pests in a ...

ecology term describing source–sink dynamics at the population level. High levels of dispersal among habitat patches allow populations to be maintained in environments that are normally outside the species environmental range. Finally, the neutral perspective describes a framework where species are essentially equivalent in their competitive and dispersal abilities, and local and regional composition and abundance are determined primarily by

stochastic Stochastic (; ) is the property of being well-described by a random probability distribution. ''Stochasticity'' and ''randomness'' are technically distinct concepts: the former refers to a modeling approach, while the latter describes phenomena; i ...

demographic Demography () is the statistics, statistical study of human populations: their size, composition (e.g., ethnic group, age), and how they change through the interplay of fertility (births), mortality (deaths), and migration. Demographic analy ...

processes and dispersal limitation. The neutral perspective was recently popularized by Stephen P. Hubbell following his groundbreaking work on the unified neutral theory of biodiversity.

References

{{Reflist Ecology