Biological integrity is associated with how "pristine" an

environment Environment most often refers to: __NOTOC__ * Natural environment, all living and non-living things occurring naturally * Biophysical environment, the physical and biological factors along with their chemical interactions that affect an organism or ...

is and its function relative to the potential or original state of an

ecosystem An ecosystem (or ecological system) consists of all the organisms and the physical environment with which they interact. These biotic and abiotic components are linked together through nutrient cycles and energy flows. Energy enters the syst ...

before human alterations were imposed. Biological integrity is built on the assumption that a decline in the values of an ecosystem's functions are primarily caused by human activity or alterations. The more an environment and its original processes are altered, the less biological integrity it holds for the

community A community is a social unit (a group of living things) with commonality such as place, norms, religion, values, customs, or identity. Communities may share a sense of place situated in a given geographical area (e.g. a country, villag ...

as a whole. If these processes were to change over time naturally, without human influence, the integrity of the ecosystem would remain intact. The integrity of the ecosystem relies heavily on the processes that occur within it because those determine what

organism In biology, an organism () is any life, living system that functions as an individual entity. All organisms are composed of cells (cell theory). Organisms are classified by taxonomy (biology), taxonomy into groups such as Multicellular o ...

s can inhabit an area and the complexities of their interactions. Most of the applications of the notion of biological integrity have addressed aquatic environments, but there have been efforts to apply the concept to terrestrial environments. Determining the pristine condition of the ecosystem is in theory scientifically derived, but deciding which of the many possible states or conditions of an ecosystem is the appropriate or desirable goal is a political or policy decision and is typically the focus of policy and political disagreements.

Ecosystem health Ecosystem health is a metaphor used to describe the condition of an ecosystem.Rapport, David (1998). "Defining ecosystem health." Pages 18-33 in Rapport, D.J. (ed.) (1998). ''Ecosystem Health.'' Blackwell Scientific. Ecosystem condition can vary ...

is a related concept but differs from biological integrity in that the "desired condition" of the ecosystem or environment is explicitly based on the values or priorities of society.

History

The concept of biological integrity first appeared in the 1972 amendments to the U.S. Federal Water Pollution Control Act, also known as the

Clean Water Act The Clean Water Act (CWA) is the primary federal law in the United States governing water pollution. Its objective is to restore and maintain the chemical, physical, and biological integrity of the nation's waters; recognizing the responsibiliti ...

. The

United States Environmental Protection Agency The Environmental Protection Agency (EPA) is an independent executive agency of the United States federal government tasked with environmental protection matters. President Richard Nixon proposed the establishment of EPA on July 9, 1970; it ...

(EPA) had used the term as a way to gauge the standards to which

water Water (chemical formula ) is an inorganic, transparent, tasteless, odorless, and nearly colorless chemical substance, which is the main constituent of Earth's hydrosphere and the fluids of all known living organisms (in which it acts as ...

should be maintained, but the vocabulary instigated years of debate about the implications of not only the meaning of biological integrity, but also how it can be

measured Measurement is the quantification of attributes of an object or event, which can be used to compare with other objects or events. In other words, measurement is a process of determining how large or small a physical quantity is as compared t ...

. EPA sponsored the first conference about the term in March 1975. The conference, called "The Integrity of Water", provided the first accepted definition of biological integrity. In 1981, EPA assembled a field of experts from the U.S.

Fish and Wildlife Service The United States Fish and Wildlife Service (USFWS or FWS) is an agency within the United States Department of the Interior dedicated to the management of fish, wildlife, and natural habitats. The mission of the agency is "working with ot ...

, academia, and its own staff to further refine the definition and identify key

indicators Indicator may refer to: Biology * Environmental indicator of environmental health (pressures, conditions and responses) * Ecological indicator of ecosystem health (ecological processes) * Health indicator, which is used to describe the health ...

to quantitatively measure biological integrity. The conference not only identified a definition, but also methods to evaluate the community, and they established that multiple sites should be used to determine the condition of the environment.

Definition

Today, the accepted definition is "the capability of supporting and maintaining a balanced, integrated, adaptive community of organisms having a

species In biology, a species is the basic unit of Taxonomy (biology), classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of ...

composition, diversity, and functional organization comparable to that of the natural

habitat In ecology, the term habitat summarises the array of resources, physical and biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species habitat can be seen as the physical ...

of the region." This definition was adapted from David Frey's paper delivered at the 1975 "Integrity of Water" conference. The implications of this definition are that living systems have a variety of scales relative to which they exist, that one can quantify the parts that sustain or contribute to a system's functioning and that all systems must be seen in the context of their environments and

evolutionary Evolution is change in the heritable characteristics of biological populations over successive generations. These characteristics are the expressions of genes, which are passed on from parent to offspring during reproduction. Variation t ...

history. This term primarily refers to aquatic environments because the vocabulary is derived from the Clean Water Act, but the concepts can be applied to other ecosystems.

Evaluation methods

In order to quantify and evaluate the biological integrity of a system, the index of biological integrity (IBI) was formulated by James Karr in 1981. In this index the baseline biological integrity (its function before human influence) and the current functions of an ecosystem are measured against one another to evaluate how much of ecosystem's function has been preserved. The IBI evaluates the ecosystem by utilizing biosurveys and comparing

species richness Species richness is the number of different species represented in an ecological community, landscape or region. Species richness is simply a count of species, and it does not take into account the abundances of the species or their relative ab ...

, indicator

taxa In biology, a taxon ( back-formation from '' taxonomy''; plural taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular n ...

, hybrids, and

invasive species An invasive species otherwise known as an alien is an introduced organism that becomes overpopulated and harms its new environment. Although most introduced species are neutral or beneficial with respect to other species, invasive species adv ...

. IBIs are used primarily to evaluate

aquatic ecosystem An aquatic ecosystem is an ecosystem formed by surrounding a body of water, in contrast to land-based terrestrial ecosystems. Aquatic ecosystems contain communities of organisms that are dependent on each other and on their environment. The t ...

s although the concept is applicable to measuring biological integrity in any natural ecosystem.

References

External links

EPA Bioindicators - Biological Integrity
*Online biomonitoring by recording bivalve mollusc activity worldwide 24/7, th
MolluSCAN ''eye''
{{Webarchive, url=https://web.archive.org/web/20161113173444/http://molluscan-eye.epoc.u-bordeaux1.fr/index.php?rubrique=accueil&lang=en , date=2016-11-13 project. Aquatic ecology Conservation biology Environmental science Water pollution

History

Definition

Evaluation methods

See also

References

External links