An index of biological integrity (IBI), also called an index of biotic integrity, is a scientific tool typically used to identify and classify water pollution problems, although there have been some efforts to apply the idea to terrestrial environments. [1] An IBI associates anthropogenic influences on a water body with biological activity in the water body, and is formulated using data developed from biosurveys. Biological 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. [2] 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, then by definition, the less biological integrity it holds for the community as a whole. If these processes were to change over time naturally, without human influence, the integrity of the ecosystem would remain intact. Similar to the concept of ecosystem health, the integrity of the ecosystem relies heavily on the processes that occur within it because those determine which organisms can inhabit an area and the complexities of their interactions. Deciding which of the many possible states or conditions of an ecosystem is appropriate or desirable is a political or policy decision. [2]
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 assess a score. Because communities naturally vary as do samples collected from a larger population, identifying robust statistics with acceptable variance is an area of active and important research.
This can be a powerful tool 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, suites 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 James Karr in 1981. [3] [4] To date IBIs have been developed for fish, algae, macroinvertebrates, pupal exuvia (shed skins of chironomidae), vascular plants, and combinations of these. Comparatively little work has been done to develop IBIs for terrestrial ecosystems.
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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 Agency (EPA). [5] 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.
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 protocol 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. [6] EPA has published guidance to assist volunteer programs in formulating IBIs and related findings. [7] 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. [8] 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 quality refers to the chemical, physical, and biological characteristics of water based on the standards of its usage. It is most frequently used by reference to a set of standards against which compliance, generally achieved through treatment of the water, can be assessed. The most common standards used to monitor and assess water quality convey the health of ecosystems, safety of human contact, extent of water pollution and condition of drinking water. Water quality has a significant impact on water supply and oftentimes determines supply options.
Water pollution is the contamination of water bodies, usually as a result of human activities, so that it negatively affects its uses. Water bodies include lakes, rivers, oceans, aquifers, reservoirs and groundwater. Water pollution results when contaminants mix with these water bodies. Contaminants can come from one of four main sources: sewage discharges, industrial activities, agricultural activities, and urban runoff including stormwater. Water pollution is either surface water pollution or groundwater pollution. This form of pollution can lead to many problems, such as the degradation of aquatic ecosystems or spreading water-borne diseases when people use polluted water for drinking or irrigation. Another problem is that water pollution reduces the ecosystem services that the water resource would otherwise provide.
The Parks Canada Agency, is the agency of the Government of Canada which manages the country's 48 National Parks, three National Marine Conservation Areas, 172 National Historic Sites, one National Urban Park, and one National Landmark. It is more commonly known by its applied title "Parks Canada". Parks Canada is mandated to "protect and present nationally significant examples of Canada's natural and cultural heritage, and foster public understanding, appreciation, and enjoyment in ways that ensure their ecological and commemorative integrity for present and future generations".
The Saint Louis River is a river in the U.S. states of Minnesota and Wisconsin that flows into Lake Superior. The largest U.S. river to flow into the lake, it is 192 miles (309 km) in length and starts 13 miles (21 km) east of Hoyt Lakes, Minnesota. The river's watershed covers 3,634 square miles (9,410 km2). Near the Twin Ports of Duluth, Minnesota and Superior, Wisconsin, the river becomes a freshwater estuary.
Freshwater ecosystems are a subset of Earth's aquatic ecosystems. They include lakes, ponds, rivers, streams, springs, bogs, and wetlands. They can be contrasted with marine ecosystems, which have a larger salt content. Freshwater habitats can be classified by different factors, including temperature, light penetration, nutrients, and vegetation. There are three basic types of freshwater ecosystems: Lentic, lotic and wetlands. Freshwater ecosystems contain 41% of the world's known fish species.
A bioindicator is any species or group of species whose function, population, or status can reveal the qualitative status of the environment. The most common indicator species are animals. For example, copepods and other small water crustaceans that are present in many water bodies can be monitored for changes that may indicate a problem within their ecosystem. Bioindicators can tell us about the cumulative effects of different pollutants in the ecosystem and about how long a problem may have been present, which physical and chemical testing cannot.
Aquatic biomonitoring is the science of inferring the ecological condition of rivers, lakes, streams, and wetlands by examining the organisms that live there. While aquatic biomonitoring is the most common form of biomonitoring, any ecosystem can be studied in this manner.
Ecological indicators are used to communicate information about ecosystems and the impact human activity has on ecosystems to groups such as the public or government policy makers. Ecosystems are complex and ecological indicators can help describe them in simpler terms that can be understood and used by non-scientists to make management decisions. For example, the number of different beetle taxa found in a field can be used as an indicator of biodiversity.
Environmental indicators are simple measures that tell us what is happening in the environment. Since the environment is very complex, indicators provide a more practical and economical way to track the state of the environment than if we attempted to record every possible variable in the environment. For example, concentrations of ozone depleting substances (ODS) in the atmosphere, tracked over time, is a good indicator with respect to the environmental issue of stratospheric ozone depletion.
A total maximum daily load (TMDL) is a regulatory term in the U.S. Clean Water Act, describing a plan for restoring impaired waters that identifies the maximum amount of a pollutant that a body of water can receive while still meeting water quality standards.
Biological 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 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 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 organisms 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 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.
The biological monitoring working party (BMWP) is a procedure for measuring water quality using families of macroinvertebrates as biological indicators.
A biotic index is a scale for showing the quality of an environment by indicating the types and abundances of organisms present in a representative sample of the environment. It is often used to assess the quality of water in marine and freshwater ecosystems. Numerous biotic indices have been created to account for the indicator species found in each region of study. The concept of the biotic index was developed by Cherie Stephens in an effort to provide a simple measurement of stream pollution and its effects on the biology of the stream.
A biosurvey, or biological survey, is a scientific study of organisms to assess the condition of an ecological resource, such as a water body.
Nutrient pollution, a form of water pollution, refers to contamination by excessive inputs of nutrients. It is a primary cause of eutrophication of surface waters, in which excess nutrients, usually nitrogen or phosphorus, stimulate algal growth. Sources of nutrient pollution include surface runoff from farm fields and pastures, discharges from septic tanks and feedlots, and emissions from combustion. Raw sewage is a large contributor to cultural eutrophication since sewage is high in nutrients. Releasing raw sewage into a large water body is referred to as sewage dumping, and still occurs all over the world. Excess reactive nitrogen compounds in the environment are associated with many large-scale environmental concerns. These include eutrophication of surface waters, harmful algal blooms, hypoxia, acid rain, nitrogen saturation in forests, and climate change.
The United States Environmental Protection Agency (EPA) was established in July 1970 when the White House and the United States Congress came together due to the public's demand for cleaner natural resources. The purpose of the EPA is to repair the damage done to the environment and to set up new criteria to allow Americans to make a clean environment a reality. The ultimate goal of the EPA is to protect human health and the environment.
The Interstate Commission on the Potomac River Basin (ICPRB) is an agency composed of commissioners representing the federal government, the states of Maryland, Pennsylvania, Virginia, West Virginia, and the District of Columbia. The ICPRB mission is to enhance, protect, and conserve the water and associated land resources of the Potomac River basin and its tributaries through regional and interstate cooperation.
Ecological assessment (EA) implies the monitoring of ecological resources, to discover the current and changing conditions. EAs are required components of most hazardous waste site investigations. Such assessments, in conjunction with contamination and human health risk assessments, help to evaluate the environmental hazards posed by contaminated sites and to determine remediation requirements.
Macroinvertebrate Community Index (MCI) is an index used in New Zealand to measure the water quality of fresh water streams. The presence or lack of macroinvertebrates such as insects, worms and snails in a river or stream can give a biological indicator on the health of that waterway. The MCI assigns a number to each species of macroinvertebrate based on the sensitivity of that species to pollution. The index then calculates an average score. A higher score on the MCI generally indicates a more healthy stream.
James R. Karr is an ecologist, ornithologist, conservation biologist, stream ecologist, academic, and author. He is a Professor Emeritus of Aquatic and Fishery Sciences at the University of Washington, Seattle.