As ecologically sensitive organisms, freshwater mussels serve as environmental indicators in the rivers and lakes they inhabit. The South Fork of the Holston River has been impounded and channelized, which can result in habitat loss of riffle and shoal areas and negatively impact native species. The aim of this study is to analyze river conditions on a roughly 40 mile stretch of the S. Fork Holston River, encompassing the distance from Eastman Chemical Company in Kingsport to Boone Lake. Information has been gathered using mussel assemblages from two archaeological sites, 40SL34 and 40SL330, and two historic collecting events, SFHSkm25.1 and SFHSkm27.0. The computer program UNIO analyzes the ecological preferences of all input taxa to compile a list of river conditions, including flow velocity and substrate. Compiling the assemblages from all four sites has revealed an increase in unfavorable conditions for many species, leading to a loss in mussel diversity. What were once the most abundant species in the archaeological sites, Ptychobranchus subtentus and Fusconaia subrotanda, both prefer to live in riffle areas with fast current. Currently, P. subtentus is listed as endangered while F. subrotanda is listed as a special concern species. The most abundant species for both historic collecting events is Lampsilis fasciola, a species that is tolerant of conditions that are unfavorable for many species. The substrate of the S. Fork Holston River, a sandy-gravel, has remained the same, but evidence suggests that impoundment has resulted in the loss of fast-moving currents and riffle areas.

Em planejamento de conservação aquática, abordagens quantitativas são realizadas ao longo de varias unidades de paisagem. Muitas vezes, as divisões internas como unidades de planejamento são definidas subjetivamente e condicionadas á disponibilidade de dados físicos y biológicos. Bacias hidrográficas como unidades de planejamento são subdividas e classificadas com base em contextos geológicos e climáticos, fisiográficos e biogeográficos que seguem escalas espaciais hierárquicas como subbacias, trechos e segmentos de rios até macro/micro habitats. Reconhecem-se fatores de grande escala espacial e temporal como condicionantes da expressão de padrões e processos (físicos e biológicos) a escalas menores e de maneira hierárquica. Mais além, existe uma interdependência destes (padrões e processos) operando através de múltiplas escalas. Na construção de abordagens de planejamento mais flexíveis e gerais, bacias e subbacias têm sido apontadas como escalas apropriadas de captura de fatores que influenciam (direta ou indiretamente) padrões biológicos observados a escalas menores. No entanto, a resolução espacial de subbacias como unidades de classificação poderia afetar os padrões encontrados? Poderia afetar também processos de planejamento de conservação? Neste contexto, analisamos a classificação de subbacias aninhadas em seis níveis hierárquicos de refinamento espacial com base em atributos topográficos da paisagem (altitude, declividade, formas de terreno, vegetação pretérita, posição de subbacias na rede, etc.) dentro da Bacia Hidrográfica do rio Taquari Antas no Rio Grande do Sul - Brasil (26000 km2). Através de uma abordagem quantitativa e análises multivariadas (ordenação e agrupamento), obtivemos basicamente o mesmo padrão espacial de organização através da hierarquia. Determinamos até oito tipos ou grupos de subbacias, influenciadas principalmente por altitude e declividade combinadas com diferentes formas de terreno e vegetação. Foram diferenciadas subbacias de planalto e planície nos extremos, e subbacias do curso principal superior, curso médio e áreas de transição desde morros altos, para morros em vales de rios encaixados, até áreas de encostas abertas e morros em planícies. Classificações com base em níveis hierárquicos de subbacias são importantes no sentido de obter alvos gerais para planejamento de conservação (como subunidades ecorregionais aquáticas). Desta maneira se contribui ao processo de geração de procedimentos e ferramentas de classificação mais flexíveis para planejamento de conservação aquática e com maior confiabilidade. / In freshwater conservation planning, quantitative classification approaches are performed across several landscape units. In general, internal divisions as planning units are subjective and depend on previous knowledge and information available. Usually, river basins are subdivided and grouped based on geology, climate, physiography and biogeographical context, following hierarchical spatial scales, such as sub-basins, reaches, segments, and macro-habitats. There is consensus that factors operating at great spatial and temporal scales constrict processes and patterns (physical and biological) expressed at finer scales, following a hierarchical organization. Furthermore, the interpendence between physical and biological patterns and processes (geomorphology, hydrology, ecology) is recognized to act at multiple scales. Towards more flexible and general planning approaches, basins and sub-basins are pointed as scales that capture the large scale factors that influence (directly or indirectly) the biological patterns observed at lower scales. Does the spatial resolution (area) of sub-basin division used to perform the classification affect the pattern obtained? Can this subject affect the conservation planning process? We analyzed the classification on Taquari Antas river basin (south Brazil) (26000 km2) along six spatially nested sub-basin classification, based on physiographic attributes. Through a quantitative approach and multivariate analyses (cluster and ordination), we obtained basically the same spatial pattern of organization across the hierarchy. The eight sub-basin types or groups where most influenced by elevation and slope, combined with landform classes and original vegetation. Extreme gradients of these attributes express plain region in the plateau and floodplains in lower gradient rivers. Between these extremes, the mainstem river and main tributaries where classified in four distinct groups of subbasins, based on the continuum of physiographical factors. Classifications based on nested hierarchical levels of sub-basins are important to get general coarse targets for freshwater conservation planning. These work contribute to the process of generating more flexible hierarchical classification frameworks for freshwater conservation planning.

Em planejamento de conservação aquática, abordagens quantitativas são realizadas ao longo de varias unidades de paisagem. Muitas vezes, as divisões internas como unidades de planejamento são definidas subjetivamente e condicionadas á disponibilidade de dados físicos y biológicos. Bacias hidrográficas como unidades de planejamento são subdividas e classificadas com base em contextos geológicos e climáticos, fisiográficos e biogeográficos que seguem escalas espaciais hierárquicas como subbacias, trechos e segmentos de rios até macro/micro habitats. Reconhecem-se fatores de grande escala espacial e temporal como condicionantes da expressão de padrões e processos (físicos e biológicos) a escalas menores e de maneira hierárquica. Mais além, existe uma interdependência destes (padrões e processos) operando através de múltiplas escalas. Na construção de abordagens de planejamento mais flexíveis e gerais, bacias e subbacias têm sido apontadas como escalas apropriadas de captura de fatores que influenciam (direta ou indiretamente) padrões biológicos observados a escalas menores. No entanto, a resolução espacial de subbacias como unidades de classificação poderia afetar os padrões encontrados? Poderia afetar também processos de planejamento de conservação? Neste contexto, analisamos a classificação de subbacias aninhadas em seis níveis hierárquicos de refinamento espacial com base em atributos topográficos da paisagem (altitude, declividade, formas de terreno, vegetação pretérita, posição de subbacias na rede, etc.) dentro da Bacia Hidrográfica do rio Taquari Antas no Rio Grande do Sul - Brasil (26000 km2). Através de uma abordagem quantitativa e análises multivariadas (ordenação e agrupamento), obtivemos basicamente o mesmo padrão espacial de organização através da hierarquia. Determinamos até oito tipos ou grupos de subbacias, influenciadas principalmente por altitude e declividade combinadas com diferentes formas de terreno e vegetação. Foram diferenciadas subbacias de planalto e planície nos extremos, e subbacias do curso principal superior, curso médio e áreas de transição desde morros altos, para morros em vales de rios encaixados, até áreas de encostas abertas e morros em planícies. Classificações com base em níveis hierárquicos de subbacias são importantes no sentido de obter alvos gerais para planejamento de conservação (como subunidades ecorregionais aquáticas). Desta maneira se contribui ao processo de geração de procedimentos e ferramentas de classificação mais flexíveis para planejamento de conservação aquática e com maior confiabilidade. / In freshwater conservation planning, quantitative classification approaches are performed across several landscape units. In general, internal divisions as planning units are subjective and depend on previous knowledge and information available. Usually, river basins are subdivided and grouped based on geology, climate, physiography and biogeographical context, following hierarchical spatial scales, such as sub-basins, reaches, segments, and macro-habitats. There is consensus that factors operating at great spatial and temporal scales constrict processes and patterns (physical and biological) expressed at finer scales, following a hierarchical organization. Furthermore, the interpendence between physical and biological patterns and processes (geomorphology, hydrology, ecology) is recognized to act at multiple scales. Towards more flexible and general planning approaches, basins and sub-basins are pointed as scales that capture the large scale factors that influence (directly or indirectly) the biological patterns observed at lower scales. Does the spatial resolution (area) of sub-basin division used to perform the classification affect the pattern obtained? Can this subject affect the conservation planning process? We analyzed the classification on Taquari Antas river basin (south Brazil) (26000 km2) along six spatially nested sub-basin classification, based on physiographic attributes. Through a quantitative approach and multivariate analyses (cluster and ordination), we obtained basically the same spatial pattern of organization across the hierarchy. The eight sub-basin types or groups where most influenced by elevation and slope, combined with landform classes and original vegetation. Extreme gradients of these attributes express plain region in the plateau and floodplains in lower gradient rivers. Between these extremes, the mainstem river and main tributaries where classified in four distinct groups of subbasins, based on the continuum of physiographical factors. Classifications based on nested hierarchical levels of sub-basins are important to get general coarse targets for freshwater conservation planning. These work contribute to the process of generating more flexible hierarchical classification frameworks for freshwater conservation planning.

Em planejamento de conservação aquática, abordagens quantitativas são realizadas ao longo de varias unidades de paisagem. Muitas vezes, as divisões internas como unidades de planejamento são definidas subjetivamente e condicionadas á disponibilidade de dados físicos y biológicos. Bacias hidrográficas como unidades de planejamento são subdividas e classificadas com base em contextos geológicos e climáticos, fisiográficos e biogeográficos que seguem escalas espaciais hierárquicas como subbacias, trechos e segmentos de rios até macro/micro habitats. Reconhecem-se fatores de grande escala espacial e temporal como condicionantes da expressão de padrões e processos (físicos e biológicos) a escalas menores e de maneira hierárquica. Mais além, existe uma interdependência destes (padrões e processos) operando através de múltiplas escalas. Na construção de abordagens de planejamento mais flexíveis e gerais, bacias e subbacias têm sido apontadas como escalas apropriadas de captura de fatores que influenciam (direta ou indiretamente) padrões biológicos observados a escalas menores. No entanto, a resolução espacial de subbacias como unidades de classificação poderia afetar os padrões encontrados? Poderia afetar também processos de planejamento de conservação? Neste contexto, analisamos a classificação de subbacias aninhadas em seis níveis hierárquicos de refinamento espacial com base em atributos topográficos da paisagem (altitude, declividade, formas de terreno, vegetação pretérita, posição de subbacias na rede, etc.) dentro da Bacia Hidrográfica do rio Taquari Antas no Rio Grande do Sul - Brasil (26000 km2). Através de uma abordagem quantitativa e análises multivariadas (ordenação e agrupamento), obtivemos basicamente o mesmo padrão espacial de organização através da hierarquia. Determinamos até oito tipos ou grupos de subbacias, influenciadas principalmente por altitude e declividade combinadas com diferentes formas de terreno e vegetação. Foram diferenciadas subbacias de planalto e planície nos extremos, e subbacias do curso principal superior, curso médio e áreas de transição desde morros altos, para morros em vales de rios encaixados, até áreas de encostas abertas e morros em planícies. Classificações com base em níveis hierárquicos de subbacias são importantes no sentido de obter alvos gerais para planejamento de conservação (como subunidades ecorregionais aquáticas). Desta maneira se contribui ao processo de geração de procedimentos e ferramentas de classificação mais flexíveis para planejamento de conservação aquática e com maior confiabilidade. / In freshwater conservation planning, quantitative classification approaches are performed across several landscape units. In general, internal divisions as planning units are subjective and depend on previous knowledge and information available. Usually, river basins are subdivided and grouped based on geology, climate, physiography and biogeographical context, following hierarchical spatial scales, such as sub-basins, reaches, segments, and macro-habitats. There is consensus that factors operating at great spatial and temporal scales constrict processes and patterns (physical and biological) expressed at finer scales, following a hierarchical organization. Furthermore, the interpendence between physical and biological patterns and processes (geomorphology, hydrology, ecology) is recognized to act at multiple scales. Towards more flexible and general planning approaches, basins and sub-basins are pointed as scales that capture the large scale factors that influence (directly or indirectly) the biological patterns observed at lower scales. Does the spatial resolution (area) of sub-basin division used to perform the classification affect the pattern obtained? Can this subject affect the conservation planning process? We analyzed the classification on Taquari Antas river basin (south Brazil) (26000 km2) along six spatially nested sub-basin classification, based on physiographic attributes. Through a quantitative approach and multivariate analyses (cluster and ordination), we obtained basically the same spatial pattern of organization across the hierarchy. The eight sub-basin types or groups where most influenced by elevation and slope, combined with landform classes and original vegetation. Extreme gradients of these attributes express plain region in the plateau and floodplains in lower gradient rivers. Between these extremes, the mainstem river and main tributaries where classified in four distinct groups of subbasins, based on the continuum of physiographical factors. Classifications based on nested hierarchical levels of sub-basins are important to get general coarse targets for freshwater conservation planning. These work contribute to the process of generating more flexible hierarchical classification frameworks for freshwater conservation planning.

Microplastics (MPs) pollution is a global ongoing issue in freshwater ecosystems. The threat of MPs has only recently been recognized and research is needed to better understand how widespread this threat is. Plastic litter is the ultimate source of MPs and we might therefore expect MPs to be a greater threat in areas of high human use. To improve our understanding of how MPs pollution might vary with human land use, we will survey for MPs in freshwater streams. To find the variation of land use this study would be sampling three major types of streams: forested, urban, and agricultural. MPs will be sampled from three streams in each landscape using 1 L grab samples. The freshwater will be filtered and MPs in each landscape will be compared using ANOVA. Each stream site will be sampled five times for a total of forty-five grab samples. The samples will take place in early spring, and sampling after a storm will be avoided to prevent bias data. The results of the project will improve our understanding of where MPs are a potential threat in East Tennessee, as well as our broader understanding of how human activity influences the distribution of this threat.

Area of Occupancy (AO) is a frequently used indicator to assess and inform designation of conservation status to wildlife species by the International Union for Conservation of Nature (IUCN). The applicability of the current grid-based AO measurement on freshwater organisms has been questioned due to the restricted dimensionality of freshwater habitats. I investigated the extent to which AO influenced conservation status for freshwater taxa at a national level in Canada. I then used distribution data of 20 imperiled freshwater fish species of southwestern Ontario to (1) demonstrate biases produced by grid-based AO and (2) develop a biologically relevant AO index. My results showed grid-based AOs were sensitive to spatial scale, grid cell positioning, and number of records, and were subject to inconsistent decision making. Use of the biologically relevant AO changed conservation status for four freshwater fish species and may have important implications on the subsequent conservation practices.

Area of Occupancy (AO) is a frequently used indicator to assess and inform designation of conservation status to wildlife species by the International Union for Conservation of Nature (IUCN). The applicability of the current grid-based AO measurement on freshwater organisms has been questioned due to the restricted dimensionality of freshwater habitats. I investigated the extent to which AO influenced conservation status for freshwater taxa at a national level in Canada. I then used distribution data of 20 imperiled freshwater fish species of southwestern Ontario to (1) demonstrate biases produced by grid-based AO and (2) develop a biologically relevant AO index. My results showed grid-based AOs were sensitive to spatial scale, grid cell positioning, and number of records, and were subject to inconsistent decision making. Use of the biologically relevant AO changed conservation status for four freshwater fish species and may have important implications on the subsequent conservation practices.

Thesis (MScConsEcol (Conservation Ecology and Entomology))--Stellenbosch University, 2008. / The great pressures on freshwaters require their conservationists and managers to develop methods to rapidly and accurately assess their condition. Dragonflies are excellent indicators of habitat integrity and are effective organisms for this purpose. However, assessment must be done at the correct spatial scale. My aim here is to optimize the spatial resolution at which species are mapped, using three different concepts and methods in freshwater invertebrate distribution mapping, with special emphasis on IUCN Red Listing. The first is the extent of occurrence (EOO) concept, using the minimum convex polygon, and the second, the area of occupancy (AOO) concept, using IUCN and quaternary catchments. The third approach uses a river layer to compare the suitability of grids as opposed to catchments in mapping. In this study I found that area estimation based on minimum convex polygons should not be encouraged for aquatic organisms. This study also suggests that the IUCN concept of area of occupancy (AOO) should be redefined simply as occurrence, referring to known point-locality presences only and, if future data allow, to known absences. The IUCN extent of occurrence (EOO), for aquatic species, should be defined as ‘the sum of the smallest hydrological units identified of presently known, inferred or projected occurrences of a taxon, excluding cases of vagrancy, that are used to estimate the threat to a taxon’. A single hydrological unit is also the conservation or management unit. Currently, that unit is the quaternary catchment. Dragonflies have excellent potential as indicators of habitat integrity. For this purpose, my aim was to develop the Dragonfly Biotic Index (DBI) for South Africa and compare the DBI to another index, the Average Taxonomic Distinctness Index (AvTD), which was believed to have potential in assessments. The DBI and AvTD are correlated, which suggests that they could be used on a complementary basis to prioritize sites. The DBI is a low-cost, easy-to-use method and is already used for measuring habitat recovery. It has great potential for environmental assessment and monitoring freshwater biodiversity, especially as a complement to freshwater quality assessments that use macroinvertebrate scores. I thus recommend its integration into freshwater management and conservation schemes.