Bioassessment can be performed through several methods and with different bioindicators. In Canadian Areas of Concern (AOC), fishes are used as a proxy for site condition. The Index of Biotic Integrity (IBI), a multimetric index for biological assessment, has been applied to fish data across Canadian AOCs to detect recovery. Previous studies, however, have indicated the IBI is not sensitive to assemblage changes characteristic of later stages of recovery. In this study, the IBI and multivariate methods were applied to data from two AOCs, the Detroit and St. Clair rivers. The results revealed that the IBI is susceptible to species substitutions within metric categories. The substitutions produced high variability within narrative ranks and rendered the IBI insensitive to changes, detected by multivariate methods, in the fish assemblage. In the absence of reference sites, the multivariate analyses were supplemented with the development of a reference condition based on best professional judgment.

Bioassessment can be performed through several methods and with different bioindicators. In Canadian Areas of Concern (AOC), fishes are used as a proxy for site condition. The Index of Biotic Integrity (IBI), a multimetric index for biological assessment, has been applied to fish data across Canadian AOCs to detect recovery. Previous studies, however, have indicated the IBI is not sensitive to assemblage changes characteristic of later stages of recovery. In this study, the IBI and multivariate methods were applied to data from two AOCs, the Detroit and St. Clair rivers. The results revealed that the IBI is susceptible to species substitutions within metric categories. The substitutions produced high variability within narrative ranks and rendered the IBI insensitive to changes, detected by multivariate methods, in the fish assemblage. In the absence of reference sites, the multivariate analyses were supplemented with the development of a reference condition based on best professional judgment.

No description available.

Hardwood bottomland ecosystems provide critical habitat for various wildlife among numerous ecosystem services. Since the 1800s, these forested wetlands have been logged and drained for agriculture. The federal government passed a series of legislative acts that protected wetlands and provided monetary support for restoration. The Wetlands Reserve Program (WRP) was established in 1990 with the goal of restoring ecological function in wetlands. Although several studies have measured plant and wildlife responses to WRP restorations, no standard protocol has been developed to monitor the state of ecological restoration at sites. Index of biotic integrity (IBI) models are commonly used to evaluate ecological function by assigning scores derived from biological characteristics measured at disturbed sites and comparing them with reference sites. Therefore, the objectives of my study were to: (1) characterize vegetation, amphibian and bird communities among 17 WRP restoration and 4 reference bottomland sites, and (2) develop IBI models for these communities to use in monitoring ecological restoration. My study was conducted across 10 counties in western Tennessee from March – August 2008, and communities were measured using standard sampling techniques. I detected 15 amphibian and 95 bird species at bottomland WRP sites, which ranged 2 – 21 years old. Anurans were common among sites, but salamanders were only detected at reference sites containing mature forests. The bird community changed predictably in response to succession, with grassland birds dominating young restoration sites and scrub-shrub and forest birds dominating older restoration and reference sites. Vegetation structure was related to site age, and a good predictor of bird community composition. Variables retained in the vegetation IBI model included density of snags, logs and overstory trees, basal area, and percent vertical cover measured using a profile board. The bird IBI model contained relative abundance of bark feeding, branch nesting, and twig nesting guilds. Presence of salamanders was the only variable in the amphibian IBI model. My results indicate that the WRP is contributing to the regional biodiversity of western Tennessee. The IBI models that I developed can be used for monitoring ecological restoration in Tennessee hardwood bottomlands; however, their applicability outside this region should be validated.

Hardwood bottomland ecosystems provide critical habitat for various wildlife among numerous ecosystem services. Since the 1800s, these forested wetlands have been logged and drained for agriculture. The federal government passed a series of legislative acts that protected wetlands and provided monetary support for restoration. The Wetlands Reserve Program (WRP) was established in 1990 with the goal of restoring ecological function in wetlands. Although several studies have measured plant and wildlife responses to WRP restorations, no standard protocol has been developed to monitor the state of ecological restoration at sites. Index of biotic integrity (IBI) models are commonly used to evaluate ecological function by assigning scores derived from biological characteristics measured at disturbed sites and comparing them with reference sites. Therefore, the objectives of my study were to: (1) characterize vegetation, amphibian and bird communities among 17 WRP restoration and 4 reference bottomland sites, and (2) develop IBI models for these communities to use in monitoring ecological restoration. My study was conducted across 10 counties in western Tennessee from March – August 2008, and communities were measured using standard sampling techniques. I detected 15 amphibian and 95 bird species at bottomland WRP sites, which ranged 2 – 21 years old. Anurans were common among sites, but salamanders were only detected at reference sites containing mature forests. The bird community changed predictably in response to succession, with grassland birds dominating young restoration sites and scrub-shrub and forest birds dominating older restoration and reference sites. Vegetation structure was related to site age, and a good predictor of bird community composition. Variables retained in the vegetation IBI model included density of snags, logs and overstory trees, basal area, and percent vertical cover measured using a profile board. The bird IBI model contained relative abundance of bark feeding, branch nesting, and twig nesting guilds. Presence of salamanders was the only variable in the amphibian IBI model. My results indicate that the WRP is contributing to the regional biodiversity of western Tennessee. The IBI models that I developed can be used for monitoring ecological restoration in Tennessee hardwood bottomlands; however, their applicability outside this region should be validated.

Made available in DSpace on 2015-04-11T13:54:41Z (GMT). No. of bitstreams: 1 DISSERTACAO_ELANE BIVAR.pdf: 1696413 bytes, checksum: 1d9a3e632491cc835156b9e2dfb03084 (MD5) Previous issue date: 2007-04-02 / Fundação de Amparo à Pesquisa do Estado do Amazonas / The Rio Tarumã-Açu is a tributary of the left edge of the Rio Negro, situated the sum of the Manaus city in the Amazon State. The rio Tarumã-Açu conservation is vital for maintenance of the quality of its hidrics resources, however, although its importance, have received little attention of the point of view from studies of ecosystems and little has been reported in relation to this environment. Therefore, this study it had as objective to evaluate the biotic integrity of the rio Tarumã-Açu, using of fish communities. The collections had been carried through with the use of a battery of gill net, during the months of december, april, july and september that correspond to the periods of flood, full, receding and dry, respectively. 353 units of fish, distributed in 82 species, 19 families had been collected and four orders. During the flood, 11 species exclusive, 13 during the full one had been collected, nine during ebb tide and 24 during dry and only one species Hypophthalmus marginatus was common in all the periods of collection. The fishes community of the rio Tarumã-Açu was also analyzed of the point of view of the trofic structure. This analysis is important, therefore alterations in the quality of the environment or the water can affect the availability of the alimentary resources them fish and to provoke alterations in the community. The category most abundant was of the omnivorous, followed for the piscivorous, detritivorous, herbivorous, insectivorous and planctivorous. The Index of Biotic Integrity (IBI) was developed to evaluate the quality of the aquatic resources. Is one about a multimetric index, or either, composition for some metric attributes or of the community of fish, each one of which represents a measurable characteristic of the biological set that dumb in previsible way with the increase or reduction stress it ambient. To evaluate the effect of the ambient alterations, in the rio Tarumã-Açu, some metric ones of the community of fish had been modified and adapted. Space, the average minor of the IBI was gotten in the point next to the estuary of the rio Tarumã-Açu, in the point the sum the average increases significantly and reaches the principle in the third point, in the room point has a small reduction in the value. These results suggest a light change in the quality of the water, to the measure that the river if moves away from the estuary. The integrity classrooms biotic of the rio Tarumã-Açu vary of poor person, in the first point, to regulating in the three following points. In relation to the hydrologic cycle bigger differences in the final value of the IIB had been found, where the classrooms vary during the hydrologic cycle of poor person in the flood to the good one in the full one and in it dries. Although the information in allow them to affirm that the degradation of the basin of the Tarumã is resultant of the disordered growth of Manaus, it is necessary to know better as the ambient modifications, that affect physics, chemistry biological and the waters of the rio Tarumã-Açu, cause a process of gradual degradation, but that it needs to be controlled, therefore, the study of monitoring of water of the rio Tarumã-Açu, on the basis of the Index of Biotic Integrity, was basic to detect space and secular differences of quality of the water and can be enclosed as a useful tool in the development of programs of monitoring in the long run of the Tarumã basin. / O rio Tarumã-Açu é um tributário da margem esquerda do rio Negro, situado a montante da cidade de Manaus no estado do Amazonas. Atualmente o rio esta sujeito a uma intensa ação antrópica e por isso a conservação e a recuperação do rio Tarumã-Açu é vital para manutenção da qualidade de seus recursos hídricos. No entanto, apesar de sua importância, tem recebido pouca atenção do ponto de vista de estudos dos ecossistemas e pouco tem sido reportado em relação a este ambiente. Por isso, este estudo teve como objetivo avaliar a integridade biótica do rio Tarumã-Açu, utilizando a comunidade de peixes como indicador de qualidade ambiental. As coletas foram realizadas com o uso de uma bateria de malhadeiras, durante os meses de dezembro 2005, abril, julho e setembro de 2006 que correspondem aos períodos de enchente, cheia, vazante e seca, respectivamente. Foram coletados 353 exemplares de peixes, distribuídos em 82 espécies, 19 famílias e quatro ordens. Durante a enchente, foram coletadas 11 espécies exclusivas, 13 durante a cheia, nove durante a vazante e 24 durante a seca e apenas uma espécie Hypophthalmus marginatus foi comum a todos os períodos de coleta. A comunidade de peixes do rio Tarumã-Açu foi analisada também do ponto de vista da estrutura trófica. Esta análise é importante, pois alterações na qualidade do ambiente ou da água podem afetar a disponibilidade dos recursos alimentares para os peixes e provocar alterações na comunidade. A categoria mais abundante foi a dos onívoros, seguida pelos piscívoros, detritívoros, herbívoros, insetívoros e planctívoros. O Índice de Integridade Biótica (IIB) foi desenvolvido para avaliar a qualidade dos recursos aquáticos. Trata-se de um índice multimétrico, ou seja, composto por vários atributos ou métricas da comunidade de peixes, cada uma das quais representa uma característica mensurável do conjunto biológico, que muda de maneira previsível com o aumento ou diminuição do estresse ambiental. Para avaliar os efeitos das alterações ambientais no rio Tarumã-Açu, algumas métricas da comunidade de peixes foram modificadas e adaptadas. Espacialmente, o menor valor do IIB foi obtido no ponto mais próximo da foz do rio Tarumã-Açu, no ponto a montante o valor aumenta significativamente e atinge o máximo no terceiro ponto, no quarto ponto há uma pequena diminuição no valor. Estes resultados indicam uma leve mudança na qualidade da água, à medida que o rio se afasta da foz. As classes de integridade biótica do rio Tarumã-Açu variam de pobre, no primeiro ponto, regular no segundo ponto, bom no terceiro ponto e regular no quarto ponto. Em relação ao ciclo hidrológico as classes variam durante o ciclo hidrológico de pobre na enchente a regular na cheia e vazante e bom na seca. Embora as informações nos permitam afirmar que a degradação da bacia do rio Tarumã-Açu é resultante do crescimento desordenado da cidade de Manaus, é necessário conhecer melhor como as modificações ambientais, que afetam física, química e biologicamente as águas do rio Tarumã-Açu causam esse processo de degradação progressiva e que precisa ser controlada.

Fish community data were used to develop an index of biotic integrity (IBI) to quantify habitat degradation in oxbow lakes of the Delta region of the Yazoo River Basin. Daytime boat electrofishing was used to sample the fish assemblage of 30 oxbow lakes during 2006-2007. We evaluated 70 candidate metrics based on their responses to measures of anthropogenic disturbance. Six metrics were retained for inclusion in the IBI: species richness, Shannon’s diversity (H’), average tolerance, and catch rates of buffalo, orangespotted sunfish, and litho-psammophilic spawners. The six IBI metrics showed strong multivariate relationships with measures of habitat degradation in a canonical correlation analysis. Spearman’s rank correlation and scatterplot analysis showed that IBI scores changed in a predictable pattern along gradients of habitat degradation. Three additional lakes were sampled in 2008 and were used to successfully validate the IBI. Biotic integrity was found to be impaired in most oxbow lakes of the Mississippi Delta.

Dentre os sistemas naturais de regiões tropicais e sub-tropicais destacam-se os ambientes aquáticos que são representados por diferentes tipos de \"habitats\" como rios, riachos e lagoas marginais. A bacia do rio Sorocaba é um exemplo destes sistemas, sendo constituída por ambientes variados e, portanto, por condições ecológicas distintas. Tendo em vista a necessidade de caracterizar tais \"habitats\" por meio de índice de integridade biótica (IBI) e de prover informações ecológicas nesta bacia, foi realizado um estudo limnológico e ictiológico em doze tributários do rio Sorocaba de quatro ordens diferentes. Foram realizadas coletas para a avaliação das variáveis físicas, químicas e biológicas nas épocas de cheia e seca, nos anos de 1999 e 2000. Onze variáveis relacionadas à organização e saúde da comunidade de peixes foram avaliadas para análise do índice de integridade biótica dos \"habitats\" aquáticos em estudo, sendo essas variáveis selecionadas de maneira a detectar impactos sobre a estrutura da comunidade. Para tanto, verificou-se a riqueza e a abundância total das espécies, além da intolerância e categoria trófica dos indivíduos. Os resultados indicaram que a organização e a saúde da comunidade de peixes foram as variáveis mais importantes para composição do índice de integridade biótica nas três diferentes ordens de rio estudadas (2ª, 3ª e 4ª). De maneira geral, a bacia do rio Sorocaba apresentou-se alterada em relação aos padrões estabelecidos para comunidade íctica nesta última década, o que é indicativo de certo grau de degradação no sistema. / Tropical and sub-tropical rivers distinguish themselves among the aquatic systems in producing different types of habitats such as rivers, stream, creeks and floodplain lakes. The Sorocaba river in the State of São Paulo, Brazil, is an example of this type of system constituted by a variety environments and, hence producing distinct ecological conditions. A limnological and ictiological study of 12 tributaries of Sorocaba river four different stream orders was conducted to characterize these habitats in relation to the index of biological integrity and also to provide ecological information about the environmental conditions on the hydrographic basin. Data on physical, chemical and biological variables were obtained in dry and wet seasons during years 1999 and 2000. Eleven variables related to the organization and integrity of the fishes communityes were evaluated for the analysis of biotic integrity index of the aquatic habitats under study. These variables were selected to detected any environmental impacts on the structure of communities. The species richness and total abundance of the species as well as the intolerance and trophic category of individual were focused for this purpose. The results indicate that the organization and well-being of the communities were the most important variables, in determining the biotic integrity index in three higher stream orders, namely 2nd, 3rd and the 4th. In general, the Sorocaba river showed alterations in relation to the established patterns for ictic communities have been indicating of a certain degree of degradation in the system.

No description available.

Dentre os sistemas naturais de regiões tropicais e sub-tropicais destacam-se os ambientes aquáticos que são representados por diferentes tipos de \"habitats\" como rios, riachos e lagoas marginais. A bacia do rio Sorocaba é um exemplo destes sistemas, sendo constituída por ambientes variados e, portanto, por condições ecológicas distintas. Tendo em vista a necessidade de caracterizar tais \"habitats\" por meio de índice de integridade biótica (IBI) e de prover informações ecológicas nesta bacia, foi realizado um estudo limnológico e ictiológico em doze tributários do rio Sorocaba de quatro ordens diferentes. Foram realizadas coletas para a avaliação das variáveis físicas, químicas e biológicas nas épocas de cheia e seca, nos anos de 1999 e 2000. Onze variáveis relacionadas à organização e saúde da comunidade de peixes foram avaliadas para análise do índice de integridade biótica dos \"habitats\" aquáticos em estudo, sendo essas variáveis selecionadas de maneira a detectar impactos sobre a estrutura da comunidade. Para tanto, verificou-se a riqueza e a abundância total das espécies, além da intolerância e categoria trófica dos indivíduos. Os resultados indicaram que a organização e a saúde da comunidade de peixes foram as variáveis mais importantes para composição do índice de integridade biótica nas três diferentes ordens de rio estudadas (2ª, 3ª e 4ª). De maneira geral, a bacia do rio Sorocaba apresentou-se alterada em relação aos padrões estabelecidos para comunidade íctica nesta última década, o que é indicativo de certo grau de degradação no sistema. / Tropical and sub-tropical rivers distinguish themselves among the aquatic systems in producing different types of habitats such as rivers, stream, creeks and floodplain lakes. The Sorocaba river in the State of São Paulo, Brazil, is an example of this type of system constituted by a variety environments and, hence producing distinct ecological conditions. A limnological and ictiological study of 12 tributaries of Sorocaba river four different stream orders was conducted to characterize these habitats in relation to the index of biological integrity and also to provide ecological information about the environmental conditions on the hydrographic basin. Data on physical, chemical and biological variables were obtained in dry and wet seasons during years 1999 and 2000. Eleven variables related to the organization and integrity of the fishes communityes were evaluated for the analysis of biotic integrity index of the aquatic habitats under study. These variables were selected to detected any environmental impacts on the structure of communities. The species richness and total abundance of the species as well as the intolerance and trophic category of individual were focused for this purpose. The results indicate that the organization and well-being of the communities were the most important variables, in determining the biotic integrity index in three higher stream orders, namely 2nd, 3rd and the 4th. In general, the Sorocaba river showed alterations in relation to the established patterns for ictic communities have been indicating of a certain degree of degradation in the system.