Ecological dominance is the degree to which one or several species have a major influence controlling the other species in their ecological community (because of their large size, population, productivity, or related factors) or make up more of the

biomass Biomass is a term used in several contexts: in the context of ecology it means living organisms, and in the context of bioenergy it means matter from recently living (but now dead) organisms. In the latter context, there are variations in how ...

. Both the composition and abundance of species within an ecosystem can be affected by the dominant species present. In most of the world's ecosystems, biologists have repeatedly observed a rank-abundance curve in which ecosystems comprise a handful of incredibly abundant species, but more numerous, rarer species that are few in number. Danish botanist Christen C. Raunkiær described this phenomenon as his " law of frequency" in 1918, in which he recognized that in communities with a single species accounting for most of the biomass, species diversity was often lower. Understandably, biologists expect to see more profound effects from those species greater in number. First formalized as the ''mass ratio hypothesis'' in a 1998 paper by English ecologist J. Philip Grime, ecologically dominant species are predicted to have overwhelming effects on ecosystem function and ecological processes due to their relatively high biomass and ubiquity. Most ecological communities are defined by their dominant species. * In many examples of wet

woodland A woodland () is, in the broad sense, land covered with woody plants (trees and shrubs), or in a narrow sense, synonymous with wood (or in the U.S., the '' plurale tantum'' woods), a low-density forest forming open habitats with plenty of sunli ...

in western

Europe Europe is a continent located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere. It is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, the Mediterranean Sea to the south, and Asia to the east ...

, the dominant tree is alder (''

Alnus glutinosa ''Alnus glutinosa'', the common alder, black alder, European alder, European black alder, or just alder, is a species of tree in the family (biology), family Betulaceae, native plant, native to most of Europe, southwest Asia and northern Africa. ...

''). * In

tallgrass prairie The tallgrass prairie is an ecosystem native to central North America. Historically, natural and Historical ecology#Anthropogenic fire, anthropogenic fire, as well as grazing by large mammals (primarily bison) provided periodic disturbances to th ...

s of Northeastern

Kansas Kansas ( ) is a landlocked U.S. state, state in the Midwestern United States, Midwestern region of the United States. It borders Nebraska to the north; Missouri to the east; Oklahoma to the south; and Colorado to the west. Kansas is named a ...

, the dominant grass is (''

Andropogon gerardi ''Andropogon gerardi'', commonly known as big bluestem, is a species of tall grass native to much of the Great Plains and grassland regions of central and eastern North America. It is also known as tall bluestem, bluejoint, and turkeyfoot. Taxon ...

i).'' * In

temperate In geography, the temperate climates of Earth occur in the middle latitudes (approximately 23.5° to 66.5° N/S of the Equator), which span between the tropics and the polar regions of Earth. These zones generally have wider temperature ran ...

bog A bog or bogland is a wetland that accumulates peat as a deposit of dead plant materials often mosses, typically sphagnum moss. It is one of the four main types of wetlands. Other names for bogs include mire, mosses, quagmire, and musk ...

s, the dominant vegetation is usually species of ''

Sphagnum ''Sphagnum'' is a genus of approximately 380 accepted species of mosses, commonly known as sphagnum moss, also bog moss and quacker moss (although that term is also sometimes used for peat). Accumulations of ''Sphagnum'' can store water, since ...

'' moss. * Tidal swamps in the

tropics The tropics are the regions of Earth surrounding the equator, where the sun may shine directly overhead. This contrasts with the temperate or polar regions of Earth, where the Sun can never be directly overhead. This is because of Earth's ax ...

are usually dominated by species of mangrove (''

Rhizophoraceae The Rhizophoraceae is a family of tropical or subtropical flowering plants. It includes around 147 species distributed in 15 genera.Setoguchi, H., Kosuge, K., & Tobe, H. (1999). Molecular Phylogeny of Rhizophoraceae Based on rbcL Gene Sequences. ...

''). * Some Arctic sea floor communities are dominated by

brittle star Brittle stars, serpent stars, or ophiuroids (; ; referring to the serpent-like arms of the brittle star) are echinoderms in the class Ophiuroidea, closely related to starfish. They crawl across the sea floor using their flexible arms for locomot ...

s. * Exposed rocky shorelines are dominated by sessile organisms such as

barnacle Barnacles are arthropods of the subclass (taxonomy), subclass Cirripedia in the subphylum Crustacean, Crustacea. They are related to crabs and lobsters, with similar Nauplius (larva), nauplius larvae. Barnacles are exclusively marine invertebra ...

s and

limpet Limpets are a group of aquatic snails with a conical gastropod shell, shell shape (patelliform) and a strong, muscular foot. This general category of conical shell is known as "patelliform" (dish-shaped). Existing within the class Gastropoda, ...

s. * The turtle ant (''

Cephalotes pusillus ''Cephalotes pusillus'' is a species of arboreal ant in the genus '' Cephalotes'', described in 1824 and characterized by its oddly shaped head and ability to glide if it falls from a tree, as gliding ant Gliding ants are arboreal ants of se ...

''), is thought to dominant arboreal ant communities in the Brazilian savannah. There are currently several different metrics for assessing species dominance in natural ecosystems, including the

importance value index The Importance Value Index (IVI) in Ecology is the quantitative measure of how dominant a species is in a given ecosystem. It combines multiple parameters to reflect a species' overall dominance, helping to describe the structure and composition o ...

competitive index Competition is a rivalry where two or more parties strive for a common goal which cannot be shared: where one's gain is the other's loss (an example of which is a zero-sum game). Competition can arise between entities such as organisms, indiv ...

community importance index A community is a social unit (a group of people) with a shared socially-significant characteristic, such as place, set of norms, culture, religion, values, customs, or identity. Communities may share a sense of place situated in a given ge ...

, and

dominance index Dominance may refer to: Social relationships * Dominance hierarchy or social hierarchy, an organizational form by which individuals within a community control the distribution of resources within the community * Dominance and submission, set of ...

References

External links

Dominant Species in a Diverse Ecosystem
{{DEFAULTSORT:Dominance (Ecology) Habitats

See also

References

External links