Index Of Biotic Integrity Scores Research Articles

An Index of Biotic Integrity: A Test with Limnological and Fish Data from Sixty Florida Lakes

An index of biotic integrity (IBI) that used eight fish assemblage metrics was examined for effectiveness in estimating anthropogenic impacts to 60 Florida lakes ranging in size from 2 ha to more than 12,400 ha. The lakes ranged in trophic status from oligotrophic to hypereutrophic and had aquatic macrophyte abundances (percent lake volume infested) ranging from less than 1% to 100%. Fish species were classified by trophic feeding guild and tolerance to increases in turbidity or warming and decreases in dissolved oxygen concentration. Fish assemblage metrics tested were as follows: Number of fish species, number of native fish species, number of Lepomis species, number of piscivorous species, number of generalist species, number of invertivore species, number of species intolerant of increased turbidity or warming and decreased dissolved oxygen concentration, and number of species tolerant of increased turbidity or warming and decreased dissolved oxygen concentration. The total IBI scores and the data used to calculate individual metrics were unable to accurately predict the degree of anthropogenic impact to 60 Florida lakes, as estimated by personal observations of local limnologists, lake chloride concentrations, and road densities in the watersheds. Lake surface area and lake trophic status have a dominant influence on the fish assemblage metrics tested in this study. Thus, the IBI approach may be of limited usefulness for predicting anthropogenic impact in lake data sets that have wide ranges of surface areas and trophic status classifications.

Large‐scale assessments of river health using an Index of Biotic Integrity with low‐diversity fish communities

Summary1. Effective tools are needed to measure the ‘health’ of rivers at scales large enough to be useful for management. Indicators for assessing the complex of variables that constitutes river health need to be ecologically based, efficient, rapid and consistently applicable in different ecological regions.2. A large‐scale survey of rivers in New South Wales, Australia provided data to test the Index of Biotic Integrity (IBI). The IBI employs the fish‐community attributes, identified using regional and river‐size data, expected for a river reach of excellent environmental quality. It uses metrics based on species richness, abundance, community structure and the health of individual fish. IBI metrics were established to suit a relatively low‐diversity and unspecialized freshwater fish fauna in south‐eastern Australia, totalling 55 species.3. The IBI was able to discriminate between relative levels of environmental quality within a diverse set of stream systems and four presumptive ecological regions. The index was validated by testing the repeatability of scores, and by comparison of IBI scores at eighty sites with an independent measure of potential catchment condition, the River Disturbance Index.4. Assessments of metric performance showed that eleven of the twelve metrics contributed satisfactorily. One metric based on trophic guild performed poorly and should be deleted from the index. Six other recommendations are made to enhance the performance of the IBI.5. Results show that, while all large rivers have been disturbed, rivers in the Murray region and those in many coastal montane areas are particularly degraded.6. The IBI results presented here demonstrate a validated method for large‐scale monitoring of river health based on a fish fauna of limited diversity, in the absence of suitable reference sites.

Fish communities and river alteration in the Seine basin and nearby coastal streams

Spatial variation of quality of fish communities in the whole Seine basin and nearby coastal streams were examined by the Index of Biotic Integrity (IBI). The relationship between quality of fish communities and river alteration was also studied. A trend of fish community degradation was found from the periphery to the centre of the basin and from upstream to downstream. This trend is conform with the gradient of anthropic pressures observed in the catchment. Variations in IBI scores were significantly related to water quality, diversity of physical habitat and substrate clogging. In headwaters, effects of water quality and substrate clogging were predominant, suggesting that fish community quality is first linked to land use in the catchment. Downstream, IBI scores were mainly linked with diversity of habitat suggesting that fish community quality principally depends on direct river bed alterations. Relationships between each metric of the IBI and the river features tended to show that reduction of habitat heterogeneity first reduced species richness, whereas degradation of water quality first affected the functional structure of the fish community. These results provide useful elements to develop a global rehabilitation of fish communities at the whole basin scale.

Use of the Index of Biotic Integrity to Assess Water Quality in Forested Streams of the Ouachita Mountains Ecoregion, Arkansas

ABSTRACT We modified the Index of Biotic Integrity (IBI) to characterize the fish assemblages and evaluate the biotic integrity of four forested streams in the Lower Ouachita Mountains Ecoregion, Arkansas. We related differences in IBI scores with corresponding differences in chemical and physical characteristics of the streams, including the varying intensities of forest management. Analysis of variance and comparison of mean IBI scores among the four streams revealed significant differences between reference and even-aged treatments and between even-aged and uneven-aged treatments (P < 0.05). Turbidity and total suspended solids were inversely related to IBI scores. Further refinement of the IBI should enable its use in the Ouachita Mountains Ecoregion to help assess site impacts, monitor trends in stream biotic integrity, and assess effectiveness of forest best management practices.

First data on an Index of Biotic Integrity (IBI) based on fish assemblages for the assessment of the impact of deforestation in a tropical West African river system

African tropical rainforests, and especially their freshwater biodiversity, are seriously threatened by ongoing industrial deforestation. Sound ecological management is needed to ensure the sustainability of these resources. For this purpose, an index of biotic integrity (IBI), based on fish assemblage characteristics, is developed in this paper. It is used to quantify the impact of industrial deforestation on freshwater biodiversity. Data from 30 non-impacted sites were used to develop a series of compositional, structural and functional metrics that reflect sites with a high biotic integrity, i.e. what a stream-fish community should look like in the absence of human perturbation. These data were compared to data collected from sites subjected to substantial forest watershed loss, in order to identify those IBI metrics that best distinguish streams with high and low biotic integrity. The overall IBI scores reflected the quality of the watershed conditions. In addition, there was a close agreement between an index of environmental quality, based on water and habitat quality and the IBI scores, suggesting that the different biological responses of the fish assemblages (observed differences in the IBI scores) were indicative of differences in physico-chemical quality of the streams. The ability of the proposed IBI to index water resource degradation, due to deforestation, suggests that it can be used as a tool for biological monitoring. However, more consistent and comprehensive data are needed to further refine the IBI, especially the assignment of integrity classes and metric threshold values.

Influences of Watershed Land Use on Habitat Quality and Biotic Integrity in Wisconsin Streams

Abstract We analyzed relationships between watershed land use and habitat quality, and between watershed land use and biotic integrity for 134 sites on 103 streams located throughout Wisconsin. Habitat quality and index of biotic integrity (IBI) scores were significantly positively correlated with the amount of forested land and negatively correlated with the amount of agricultural land in the entire watershed and in a 100-m-wide buffer along the stream. Correlations were generally stronger for the entire watershed than for the buffer. Relationships between forested land and habitat and biotic integrity were linear, although there were several outlying sites with lower-than-expected IBI scores. Relationships with agricultural land use were more complex, with an obvious decline in habitat quality and IBI scores apparent only when agricultural land use exceeded 50%. Even when agricultural land use exceeded 80%, some sites maintained relatively good habitat quality and biotic integrity. These “good” sites te...

Influence of Stream Location in a Drainage Network on the Index of Biotic Integrity

Abstract The index of biotic integrity (IBI) has become a widely used tool for assessing the condition of stream fish communities and the overall biological status of streams. Because the location of a stream in a drainage network can influence the species richness offish communities and because species richness is an important component of the IBI, we examined the influence of stream spatial location on the IBI. We found that IBI scores for headwater streams in three Illinois drainage basins were significantly lower than those calculated for tributary streams of similar size connecting directly to larger streams. This difference in IBI was related to the increased species richness and to a greater number of sucker and darter species in tributaries that drain into larger, main-channel streams. Because of the influence of tributary location on the IBI, expected values for headwater tributary streams should be developed independently from those developed for main-channel tributary streams. Failure to do so ...

Modification of an index of biotic integrity based on fish assemblages to characterize rivers of the Seine Basin, France

The Index of Biotic Integrity (IBI) is a measure of fish assemblage ‘health’ that has been used to assess catchment and stream quality throughout North America. It reflects human perturbations on natural environmental structures and processes. While preserving the ecological foundation of the original North American metrics, we have modified and adapted the IBI to the mainstem Seine River and its major tributaries in France. This successful modification of the IBI to a considerably different fish fauna on a different continent further supports its wider use outside the midwestern United States. Using data collected in 1967, 1981, and 1988–1989 from a total of 46 sites, we show spatial and temporal variation in the Seine as indicated by IBI scores. Statistically significant relationships were found between IBI and catchment area but insignificant relationships existed between IBI and an independent Water Quality Index (WQI) based on water chemistry. Comparisons between the IBI and the WQI indicate that the former is a more sensitive and robust measure of water body quality. Our results demonstrate that the IBI, combined with a statistically designed national monitoring program, would offer a reliable means of assessing spatial patterns and temporal trends in water body improvement or degradation in France. The more primitive fish families in the Basin were affected first by perturbations. These families include all the diadromous species found in the Seine and suggest serious disruption of their life histories.

Modification and Assessment of an Index of Biotic Integrity to Quantify Stream Quality in Southern Ontario

A multivariate measure of stream quality, the Index of Biotic Integrity (IBI), was adapted to southern Ontario and calibrated to watershed land use on a variety of spatial scales. The fish fauna at 209 stream locations on 10 watersheds near Toronto, Ontario, was sampled with a backpack electrofisher in the summers of 1984 and 1985 to provide biological information for the IBI. Watershed urbanization, forest cover, and riparian forest were measured from 1:50,000 scale topographic maps and related to IBI estimates by linear regression. Of the biological measures tested, species richness, local indicator species (brook trout (Salvelinus fontinalis) and Rhinichthys spp.), abundance of large piscivores, fish abundance, and incidence of blackspot disease were found to contribute significantly to IBI estimates. Variation in IBI estimates at the same location ranged from 0 to 8% within the sample season and from 0 to 24% between years. Linear models based on measures of watershed urbanization and forest cover accounted for 11–78% of the variation in IBI scores, depending on the spatial scale of the analysis. Significant IBI/land use relationships were found with whole-basin IBI estimates and for IBI estimates from individual stream reaches. Land use immediately upstream of sample stations was most strongly associated with stream quality as measured by the IBI.