Index of biological integrity
Encyclopedia
An Index of Biological Integrity (IBI), also called an Index of Biotic Integrity, is a scientific tool used to identify and classify water pollution
problems. An IBI associates anthropogenic
influences on a water body with biological activity in the water body, and is formulated using data developed from biosurvey
s.
with acceptable variance is an area of active research.
This is the most powerful tool existing to identify systemic impacts on the health
of biological systems. IBIs are increasingly involved in the identification of impairment, and confirmation of recovery
of impaired waters, in the Total Maximum Daily Load
process required by the Clean Water Act
in the USA.
Unlike chemical testing of water samples, which gives brief snap-shots of chemical concentrations, an IBI captures an integrated net impact on a biological community structure. While the complete absence, particularly sudden disappearance of, suits of indicator species
can constitute powerful evidence of a specific pollutant or stress factor, IBIs generally do not resolve a specific cause of impairment.
The IBI concept was formulated by Dr. James Karr in 1981. To date IBIs have been developed for fish
, algae
, macroinvertebrates, pupal exuvia
(shed skins of chironomidae
), vascular plants, and combinations of these.
(EPA). Such protocols provide a structure for developing an IBI, which may include measures such as richness of taxa (species, genera
, etc.) and proportion of pollution-tolerant or intolerant taxa.
variations require careful testing. Ongoing quality control
by established experts is needed to maintain data integrity, and the analysis of IBI results becomes more complex. Use of trained volunteers is being pioneered by government agencies responsible for monitoring large numbers of water bodies with limited resources, such as the Minnesota
Pollution Control Agency (MPCA) and local volunteer stream monitoring programs supported by MPCA. EPA has published guidance to assist volunteer programs in formulating IBIs and related findings. While IBIs from such programs are legally admissible in US courts, defending the validity of conclusions based solely on such results is unlikely to be feasible.
Agreement among multiple IBIs from data collected by established professionals can be more conclusive. A case in point is the phenomenon that stream IBI scores indicate significant impairment, or partial ecological collapse
where more than 10 to 15 percent of the immediately surrounding watershed
is impervious
due to urbanization
. Identifying reasons for such impairments, and possible exceptions to these trends, are major research challenges for academics studying cumulative watershed effects, and the use of Low Impact Development
techniques to mitigate the impacts of stormwater
runoff
pollution.
Water pollution
Water pollution is the contamination of water bodies . Water pollution occurs when pollutants are discharged directly or indirectly into water bodies without adequate treatment to remove harmful compounds....
problems. An IBI associates anthropogenic
Anthropogenic
Human impact on the environment or anthropogenic impact on the environment includes impacts on biophysical environments, biodiversity and other resources. The term anthropogenic designates an effect or object resulting from human activity. The term was first used in the technical sense by Russian...
influences on a water body with biological activity in the water body, and is formulated using data developed from biosurvey
Biosurvey
A biosurvey, or biological survey, is a scientific study of organisms to assess the condition of an ecological resource, such as a water body.-Overview:...
s.
Overview
To quantitatively assess changes in the composition of biologic communities, IBIs are developed to accurately reflect the ecological complexity from statistical analysis. There is no one universal IBI, and developing metrics that consistently give accurate assessment of the monitored population requires rigorous testing to confirm its validity for a given subject. Often IBIs are region-specific and require experienced professionals to provide sufficient quality data to correctly asses a score. Because communities naturally vary as do samples collected from a larger population, identifying robust statisticsStatistics
Statistics is the study of the collection, organization, analysis, and interpretation of data. It deals with all aspects of this, including the planning of data collection in terms of the design of surveys and experiments....
with acceptable variance is an area of active research.
This is the most powerful tool existing to identify systemic impacts on the health
Health
Health is the level of functional or metabolic efficiency of a living being. In humans, it is the general condition of a person's mind, body and spirit, usually meaning to be free from illness, injury or pain...
of biological systems. IBIs are increasingly involved in the identification of impairment, and confirmation of recovery
Recovery
-Health:* Healing* Cure* The Recovery model of mental distress/disorder* Recovery International, a self-help mental health program based on the work of the late Abraham A...
of impaired waters, in the Total Maximum Daily Load
Total Maximum Daily Load
A Total Maximum Daily Load is a regulatory term in the U.S. Clean Water Act, describing a value of the maximum amount of a pollutant that a body of water can receive while still meeting water quality standards...
process required by the Clean Water Act
Clean Water Act
The Clean Water Act is the primary federal law in the United States governing water pollution. Commonly abbreviated as the CWA, the act established the goals of eliminating releases of high amounts of toxic substances into water, eliminating additional water pollution by 1985, and ensuring that...
in the USA.
Unlike chemical testing of water samples, which gives brief snap-shots of chemical concentrations, an IBI captures an integrated net impact on a biological community structure. While the complete absence, particularly sudden disappearance of, suits of indicator species
Indicator species
An indicator species is any biological species that defines a trait or characteristic of the environment. For example, a species may delineate an ecoregion or indicate an environmental condition such as a disease outbreak, pollution, species competition or climate change...
can constitute powerful evidence of a specific pollutant or stress factor, IBIs generally do not resolve a specific cause of impairment.
The IBI concept was formulated by Dr. James Karr in 1981. To date IBIs have been developed for fish
Fish
Fish are a paraphyletic group of organisms that consist of all gill-bearing aquatic vertebrate animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish, as well as various extinct related groups...
, algae
Algae
Algae are a large and diverse group of simple, typically autotrophic organisms, ranging from unicellular to multicellular forms, such as the giant kelps that grow to 65 meters in length. They are photosynthetic like plants, and "simple" because their tissues are not organized into the many...
, macroinvertebrates, pupal exuvia
Exuvia
Exuviae is a term used in biology to describe the remains of an exoskeleton and related structures that are left after ecdysozoans have moulted...
(shed skins of chironomidae
Chironomidae
Chironomidae are a family of nematoceran flies with a global distribution. They are closely related to the Ceratopogonidae, Simuliidae, and Thaumaleidae...
), vascular plants, and combinations of these.
Biosurvey protocols
Biosurvey protocols have been published for use in different waterbody types and ecoregions. One such publication is the Rapid Bioassessment Protocol for streams and rivers, issued by the U.S. Environmental Protection AgencyUnited States Environmental Protection Agency
The U.S. Environmental Protection Agency is an agency of the federal government of the United States charged with protecting human health and the environment, by writing and enforcing regulations based on laws passed by Congress...
(EPA). Such protocols provide a structure for developing an IBI, which may include measures such as richness of taxa (species, genera
Genera
Genera is a commercial operating system and development environment for Lisp machines developed by Symbolics. It is essentially a fork of an earlier operating system originating on the MIT AI Lab's Lisp machines which Symbolics had used in common with LMI and Texas Instruments...
, etc.) and proportion of pollution-tolerant or intolerant taxa.
Developing IBIs with Volunteer and Professional Staff
It is possible to create IBIs for use by minimally-trained monitoring personnel, however the precision obtainable is lower than that conducted by trained professionals. Safeguards to assure robustness in spite of potential misidentifications or protocolProtocol (natural sciences)
In the natural sciences a protocol is a predefined written procedural method in the design and implementation of experiments. Protocols are written whenever it is desirable to standardize a laboratory method to ensure successful replication of results by others in the same laboratory or by other...
variations require careful testing. Ongoing quality control
Quality control
Quality control, or QC for short, is a process by which entities review the quality of all factors involved in production. This approach places an emphasis on three aspects:...
by established experts is needed to maintain data integrity, and the analysis of IBI results becomes more complex. Use of trained volunteers is being pioneered by government agencies responsible for monitoring large numbers of water bodies with limited resources, such as the Minnesota
Minnesota
Minnesota is a U.S. state located in the Midwestern United States. The twelfth largest state of the U.S., it is the twenty-first most populous, with 5.3 million residents. Minnesota was carved out of the eastern half of the Minnesota Territory and admitted to the Union as the thirty-second state...
Pollution Control Agency (MPCA) and local volunteer stream monitoring programs supported by MPCA. EPA has published guidance to assist volunteer programs in formulating IBIs and related findings. While IBIs from such programs are legally admissible in US courts, defending the validity of conclusions based solely on such results is unlikely to be feasible.
Agreement among multiple IBIs from data collected by established professionals can be more conclusive. A case in point is the phenomenon that stream IBI scores indicate significant impairment, or partial ecological collapse
Ecological collapse
Ecological Collapse refers to a situation where an ecosystem suffers a drastic, if not permanent, reduction in carrying capacity for all organisms, often resulting in mass extinction...
where more than 10 to 15 percent of the immediately surrounding watershed
Drainage basin
A drainage basin is an extent or an area of land where surface water from rain and melting snow or ice converges to a single point, usually the exit of the basin, where the waters join another waterbody, such as a river, lake, reservoir, estuary, wetland, sea, or ocean...
is impervious
Impervious surface
Impervious surfaces are mainly artificial structures--such as pavements that are covered by impenetrable materials such as asphalt, concrete, brick, and stone--and rooftops...
due to urbanization
Urbanization
Urbanization, urbanisation or urban drift is the physical growth of urban areas as a result of global change. The United Nations projected that half of the world's population would live in urban areas at the end of 2008....
. Identifying reasons for such impairments, and possible exceptions to these trends, are major research challenges for academics studying cumulative watershed effects, and the use of Low Impact Development
Low impact development
Low-impact development is a term used in the United States to describe a land planning and engineering design approach to managing stormwater runoff. LID emphasizes conservation and use of on-site natural features to protect water quality...
techniques to mitigate the impacts of stormwater
Stormwater
Stormwater is water that originates during precipitation events. It may also be used to apply to water that originates with snowmelt that enters the stormwater system...
runoff
Surface runoff
Surface runoff is the water flow that occurs when soil is infiltrated to full capacity and excess water from rain, meltwater, or other sources flows over the land. This is a major component of the water cycle. Runoff that occurs on surfaces before reaching a channel is also called a nonpoint source...
pollution.
See also
- BioindicatorBioindicatorBiological indicators are species used to monitor the health of an environment or ecosystem. They are any biological species or group of species whose function, population, or status can be used to determine ecosystem or environmental integrity. An example of such a group are the copepods and other...
- Biological integrityBiological integrityBiological integrity is associated with how “pristine” an environment is and its function relative to the potential or original state of an ecosystem before human alterations were imposed. Biological integrity is built on the assumption that a decline in the values of an ecosystem's functions are...
- Biological monitoring working partyBiological monitoring working partyThe biological monitoring working party is a procedure for measuring water quality using species of macroinvertebrates as biological indicators....
- Biotic indexBiotic indexBiotic Index is a scale for showing the quality of an environment by indicating the types of organisms present in it. It is often used to assess the quality of water in rivers. It is measured from 1 to 10 and corresponds to the four basic water quality . The concept of the Biotic Index was...
- Water qualityWater qualityWater quality is the physical, chemical and biological characteristics of water. It is a measure of the condition of water relative to the requirements of one or more biotic species and or to any human need or purpose. It is most frequently used by reference to a set of standards against which...
External links
- Benthic Index of Biological Integrity (B-IBI) for the Puget Sound Lowlands - SalmonWeb / University of Washington
- An Introduction to the Index of Biotic Integrity - U.S. Environmental Protection Agency