Organisms as Ecosystem Engineers

Abstract

JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact support@jstor.org..Wiley-Blackwell and Nordic Society Oikos are collaborating with JSTOR to digitize, preserve and extend access to Oikos. M. 1994. Organisms as ecosystem engineers.-Oikos 69: 373-386.Ecosystem engineers are organisms that directly or indirectly modulate the availability of resources to other species, by causing physical state changes in biotic or abiotic materials. In so doing they modify, maintain and create habitats. Autogenic engineers (e.g. corals, or trees) change the environment via their own physical structures (i.e. their living and dead tissues). Allogenic engineers (e.g. woodpeckers, beavers) change the environment by transforming living or non-living materials from one physical state to another, via mechanical or other means. The direct provision of resources to other species, in the form of living or dead tissues is not engineering. Organisms act as engineers when they modulate the supply of a resource or resources other than themselves. We recognise and define five types of engineering and provide examples. Humans are allogenic engineers par excellence, and also mimic the behaviour of autogenic engineers, for example by constructing glasshouses. We explore related concepts including the notions of extended phenotypes and keystone species. Some (but not all) products of ecosystem engineering are extended phenotypes. Many (perhaps most) impacts of keystone species include not only trophic effects, but also engineers and engineering. Engineers differ in their impacts. The biggest effects are attributable to species with large per capita impacts, living at high densities, over large areas for a long time, giving rise to structures that persist for millennia and that modulate many resource flows (e.g. mima mounds created by fossorial rodents). The ephemeral nests constructed by small, passerine birds lie at the opposite end of this continuum. We provide a tentative research agenda for an exploration of the phenomenon of organisms as ecosystem engineers, and suggest that all habitats on earth support, and are influenced by, ecosystem engineers.

Sediment and nutrient storage in a beaver engineered wetland

“…Beavers are often termed ecosystem engineers (Jones et al ., 1994). They can extensively modify riparian and river systems to create habitats more suitable for habitation (McKinstry et al ., 2001; Nyssen et al ., 2011; Nummi and Holopainen, 2014).…”

Metabolic theory predicts whole-ecosystem properties

“…Although it has long been recognized that different kinds of organisms play important roles in the processing of energy and materials in ecosystems, existing treatments are incomplete. Most studies have focused on particular trophic levels, such as primary producers or herbivores, specific ecosystem types, such as tropical forest or pelagic marine, or single species, such as top predators or ecosystem engineers (4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14). Still missing is a simple mechanistic theory that can make precise, quantitative predictions based on the mechanistic relationships between traits of the organisms in the different trophic levels and whole-ecosystem properties, such as carbon flux or recycling.…”

Wastewater use in agriculture and potential effects on meso and macrofauna soil

“…The Oligochaeta order is one of the most important groups in terms of changes in soil structure and high sensitivity to the input of harmful compounds. Their activities lead to the creation of biogenic structures (galleries and coprolites), which modify the physical properties of the soil where they live and the availability of resources for other organisms (JONES et al, 1994). LAVELLE & SPAIN (2001), point out that the mechanical action on the soil, contribute to the formation of stable aggregates and protect the organic matter from the rapid mineralization, is also a potential source of nutrients available to plants.…”