Dissertations / Theses: 'Macroinvertebrates'

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Possetti, Rafaela Bermudez. "Avaliação do impacto da estação de tratamento de esgoto (ETE) do município de Araraquara - SP, no manancial Ribeirão das Cruzes, pela utilização dos macroinvertebrados aquáticos como bioindicadores." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/18/18138/tde-11052016-112455/.

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Os recursos hídricos são de grande importância para a vida, já que fazem parte dos processos metabólicos dos seres vivos. No decorrer dos anos, o aumento da atividade humana e seus consequentes impactos tem acarretado maior preocupação com a conservação destes recursos. Para que haja consumo de água pelos seres humanos, há a necessidade do tratamento da mesma, retirando-se as impurezas, deixando-a potável. Assim, os efluentes provenientes das atividades humanas, especialmente dos esgotos domésticos, devem ser tratados com precaução antes de serem lançados no corpo receptor diminuindo, de tal modo, a possibilidade de impactos ambientais. Nos ecossistemas aquáticos, os macroinvertebrados aquáticos têm sido utilizados nos últimos anos como ferramenta para avaliações da qualidade ambiental. Sabendo-se da problemática ocasionada pelo despejo de efluentes domésticos em rios e córregos, este trabalho apresenta como objetivo estudar a comunidade de macroinvertebrados do Ribeirão das Cruzes nas áreas à montante e à jusante do recebimento dos efluentes do sistema de tratamento de esgoto do Município de Araraquara. Os macroinvertebrados foram coletados em duas épocas do ano em quatro pontos distintos, utilizando-se rede em \"D\" pelo método de varredura. Juntamente à coleta, foram tomadas medidas in loco do teor de oxigênio dissolvido, pH, condutividade elétrica, temperatura da água, sedimento para determinação do teor de matéria orgânica e água para análise de fósforo e nitrogênio total. Os organismos foram identificados até o nível de família exceto Chironomidae identificados até gêneros ou espécie para posterior aplicação de índices bióticos e comunitários. Os resultados apontam que houve alteração na estrutura comunitária e diminuição na riqueza de macroinvertebrados aquáticos, após a ETE (estação de tratamento de esgoto) de Araraquara. A presença exclusiva do gênero Chironomus no ponto após a ETE aponta para um elevado impacto ambiental.
The hydric resources are essential to life, since they are part of the metabolic processes in living organisms. Along the years, as human activity has increased and its consequent impacts have caused a high concern in order to preserve such resources. In order to have water consumption by humans, it needs to be treated, making it potable. Thus, effluents that originate in human activities - especially domestic sewage - must be treated before being released to the receiving water body, reducing the possibility of environmental impact. In aquatic ecosystems, macroinvertebrates are being used along the last years as a tool to evaluate environmental quality. Once known the problem caused by the release of domestic effluents in rivers and streams, the present project aims to study the macroinvertebrates community within the Cruzes stream, upstream and downstream the area of wastewater treatment effluents from Araraquara municipality. The macroinvertebrates were collected in two seasons of the year at four different points, using network \"D\" by kick sampling method. Along the collection, steps were taken in place of the dissolved oxygen content, pH, electrical conductivity, water temperature, sediment to determine the content of organic matter and water for phosphorus and total nitrogen analysis. The organisms were identified at family level except Chironomidae identified to genera or species for subsequent application of biotic and community levels. The results show that there were changes in the community structure and a decrease in the richness of aquatic macroinvertebrates after the ETE (Treatment Sewage Station) in Araraquara. The exclusive presence Chironomus genre at the point after ETE points to a high environmental impact.

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Pinder, Adrian. "Ecology of macroinvertebrates in seasonal wetlands." Thesis, Pinder, Adrian (1986) Ecology of macroinvertebrates in seasonal wetlands. Honours thesis, Murdoch University, 1986. https://researchrepository.murdoch.edu.au/id/eprint/41489/.

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Two seasonal lakes on the Swan Coastal Plain, Western Australia - Forrestdale Lake and Thomsons Lake - were sampled for macroinvertebrates over a period of six months. Three sites were chosen at each lake along a 500m transect from the fringing vegetation to the lake centres. The lakes were sampled when dry to determine which, if any, macroinvertbrates remained in the exposed sediments during the dry phase. The lakes began to fill in May, and sampling was carried out at flooded sites in May, June and July. Between June and August the water was sampled for nutrients (nitrogen and phosphorus), chlorophyll a, pH and conductivity. Organic content was measured in all samples of the sediments. The water chemistry and organic content measurements revealed that both of the lakes were freshwater and meso-eutrophic. Altogether 78 taxa of macroinvertebrates were found, (62 species in Thomsons Lake excluding the zooplankton, and 41 in Forrestdale Lake). Thirteen species were recorded from the dry lake beds, and these and the rest of the aquatic fauna were considered to be well adapted to the seasonal cycle of drying and flooding. After flooding, species richness, density of individuals and diversity increased at most sites on each sampling occasion. Temporal differences between sites were greater than spatial differences. The class lnsecta contained the largest number of species but a crustacean group, the Ostracoda, was the most abundant in terms of numbers of individuals. Sites near the fringing vegetation were found to contain the most species and have the highest density of individuals. The two lakes appear to be very productive, in terms of species richness and density of individuals, compared to other Australian wetlands. This is probably due to the trophic status of the lakes and their seasonal nature, both of which are thought to increase lentic production.

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Béjar, Maceiras María. "Interactions between sediment transport, physical habitat and benthic communities in a mountainous river affected by natural and human disturbances." Doctoral thesis, Universitat de Lleida, 2018. http://hdl.handle.net/10803/664346.

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Aquesta tesi presenta noves idees sobre les interaccions entre processos físics (transport de sediments, cabal i hàbitat) i ecològics (comunitats bentòniques, deriva de macroinvertebrats) resultants de pertorbacions naturals (afluents, riuades) i antròpiques (extraccions d’àrids a la llera i hidro-puntes o embolades) en un riu de muntanya (tram alt del riu Cinca, vessant Sud dels Pirineus). S’analitzen processos i interaccions a múltiples escales temporals (des de l’escala instantània a l’anual) i espacials (des del nivell de partícula fins el tram fluvial). La identificació de les escales d’interacció, així com l’ús de noves tècniques de mostreig han demostrat ser rellevants per a l’estudi de la relació espècie-hàbitat i constitueixen, conseqüentment, un nou exemple d’integració eco-geomorfològica que permet millorar el coneixement dels sistemes fluvials i recolza la gestió sostenible dels ecosistemes associats.
Esta tesis doctoral analiza las interacciones entre los procesos físicos (transporte de sedimentos, caudal y hábitat) y ecológicos (comunidades bentónicas, deriva de macroinvertebrados) afectados por perturbaciones naturales (crecidas y entrada de afluentes) y antrópicas (extracción de áridos e hidropuntas) en un rio de montaña (el alto Cinca, en el sur de los Pirineos). Dichos procesos y sus interacciones se han evaluado desde una escala instantánea hasta anual, y desde la escala de partícula a la escala de tramo. La identificación de las escalas de interacción así como el uso de nuevas técnicas de muestreo han demostrado ser relevantes para el estudio de la relación especie-hábitat y constituyen, por ello, un nuevo ejemplo de integración eco-geomorfológica que contribuye al conocimiento de los sistemas fluviales y apoya la gestión sostenible de los mismos.
This doctoral thesis presents new insights on the interactions between physical (sediment transport, flow and habitat) and ecological (benthic communities, macroinvertebrate drift) processes driven by natural (tributaries, floods) and human disturbances (gravel mining and hydropeaking) in a montane river (the upper Cinca, Southern Pyrenees). The work addresses processes and interactions spanning instantaneous to annual temporal scales, and from grain to river reach scale. Identification of the key scales of interaction and the integration of sampling techniques that provide continuous and high density measurements are shown to provide sound knowledge into species-habitat relations and, in turn, a firm evidence supporting the rational assessment and sustainable management of fluvial ecosystems.

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Christman, Van D. "Ecology of benthic macroinvertebrates in experimental ponds." Diss., This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-07282008-134927/.

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Johansson, Andreas. "Effects of beaver dams on benthic macroinvertebrates." Thesis, Uppsala universitet, Institutionen för biologisk grundutbildning, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-396803.

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In the 1870's the beaver (Castor fiber), population in Sweden had been exterminated. Thebeaver was reintroduced to Sweden from the Norwegian population between 1922 and 1939.Today the population has recovered and it is estimated that the population of C. fiber in all ofEurope today ranges around 639,000 individuals. The main aim with this study was toinvestigate if there was any difference in species diversity between sites located upstream anddownstream of beaver ponds. I found no significant difference in species diversity betweenthese sites and the geographical location of the streams did not affect the species diversity.This means that in future studies it is possible to consider all streams to be replicates despiteof geographical location. The pond age and size did on the other hand affect the speciesdiversity. Young ponds had a significantly higher diversity compared to medium-aged ponds.Small ponds had a significantly higher diversity compared to medium-sized and large ponds.The upstream and downstream reaches did not differ in terms of CPOM amount but somewater chemistry variables did differ between them. For the functional feeding groups I onlyfound a difference between the sites for predators, which were more abundant downstream ofthe ponds.

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Lage, Fernanda. "Aplicação da tríade de qualidade do sedimento em análise espacial no reservatório do Guarapiranga (SP, Brasil)." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/41/41134/tde-19032014-141437/.

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Com o intuito de conhecer o histórico da comunidade bentônica no reservatório do Guarapiranga para futuro estudo sobre a influência das diferentes formas de poluição na represa sobre o zoobentos, este trabalho foi desenvolvido a fim de coletar dados históricos da fauna de fundo e se houve variação na estrutura da comunidade ou não. Foram analisados quatro trabalhos realizados no período de inverno em quatro regiões médio-profundal do reservatório (Guarapiranga, Embu-Mirim, Embu-Guaçu e Parelheiros) ao longo dos anos, 1939, 1976, 1996 e 2010. A riqueza de dados presentada nos trabalhos refletiu a evolução do conhecimento em estudos limnológicos no Brasil e no mundo. A densidade de Oligochaeta apresentou aumento ao longo dos anos, assim como a de Chaoboridae. Por outro lado, Chironomidae que apresentava 30% em 1974 é pouco representativo em 2010. O ambiente mostrou forte e crescente enriquecimento orgânico em todos os pontos ao longo dos anos e isso colaborou para uma maior diversidade de grupos detritívoros (Tubificinae e Naidinae - Oligochaeta), por exemplo. Os níveis de oxigênio dissolvido no fundo diminuíram ao longo dos anos em todos as regiões. Chama-se a atenção para a necessidade de biomonitoramento nas 4 regiões da represa, utilizando inclusive os macroinvertebrados bentônicos e análises físicas e químicas do sedimento e a adoção de uma nova forma de gerenciamento deste manancial
With the purpose to know the history of the benthic community in Guarapiranga reservoir for future study about the influence of different sources of pollution in the reservoir over zoobenthos, this study was conducted to collect historical data of benthic fauna and variation in community structure. Four studies conducted during winter in four regions of the reservoir medium-profundal (Guarapiranga, Embu-Mirim, Embu-Guaçu and Parelheiros) over the years, 1939, 1976, 1996 and 2010 were analysed. The best richness of data presented in the works reflected the evolution of knowledge in limnological studies, in Brazil and worldwide. The density of Oligochaeta had an increase over the years as well as the Chaoboridae. On the other hand, Chironomidae presented 30% in the 70\' community and was not representative anymore in 2010. The environment showed strong organic enrichment for all regions along the years, and this has contributed to a greater diversity of detritivorous groups (Tubificinae and Naidinae - Oligochaeta), for example. The dissolved oxygen levels at the bottom declined over the years in all regions. Attention is called to the necessity of biomonitoring in 4 regions of the reservoir, using benthic macroinvertebrates and physical and chemical sediment analyses and the adoption of a new way of managing this system

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Faísca, Pedro Miguel Portela. "Comparison of organic matter decomposition between natural and artificial ponds." Master's thesis, Universidade de Évora, 2019. http://hdl.handle.net/10174/24405.

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Litter decomposition is a key ecosystem service within aquatic ecosystems and is a complex process that is sensitive to environmental factors. The role of microbial and macrofaunal decomposers, and how it changes across environmental gradients is not yet fully understood. Decomposition was assessed across 6 biogeographical regions to determine the role of macroinvertebrates in this ecosystem service. Decomposition was estimated using standardized cotton strips, which were deployed in the mesocosms of each region. The role of macroinvertebrates was tested with an exclusion experiment which allowed or prevented the access of macroinvertebrates to cotton strips, a similar experiment was also conducted in natural ponds. After 64 days the cotton strips were collected, and mass loss and tensile strength were measured. There were significant differences in the rate of decomposition across different regions and no differences were found between systems. Macroinvertebrates played an important role, with gatherers being major players; Resumo: A decomposição é um serviço de ecossistema chave e um processo complexo sensível a factores ambientais. O papel de decompositores microbianos e da macrofauna, e como este papel muda num gradiente ambiental não é completamente entendido. A decomposição foi avaliada em 6 zonas biogeográficas para determinar o papel de macroinvertebrados neste serviço de ecossistema. A decomposição foi estimada utilizando tiras de algodão, colocadas em mesocosmos nas diferentes regiões. O papel dos macroinvertebrados foi testado através de uma experiência de exclusão que permitia ou impedia o acesso de macroinvertebrados às tiras, uma experiência semelhante foi realizada em charcos naturais. Ao fim de 64 dias, as tiras de algodão foram recolhidas e a perda de massa e tensão foram quantificadas. Encontraram-se diferenças significativas na decomposição entre as diferentes regiões, mas não se observaram diferenças entre sistemas. Os macroinvertebrados têm um papel importante neste serviço de ecossistema, sendo as espécies colectoras as mais importantes

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Mendoza, Barberá Guillermo de. "Lake macroinvertebrates and the altitudinal gradient in the Pyrenees / Los macroinvertebrados lacustres y el gradiente altitudinal en los Pirineos." Doctoral thesis, Universitat de Barcelona, 2013. http://hdl.handle.net/10803/120427.

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“Lake macroinvertebrates and the altitudinal gradient in the Pyrenees [Los macroinvertebrados lacustres y el gradiente altitudinal en los Pirineos]” is a thesis about freshwater macroinvertebrate communities inhabitting the littoral zone of the mountain lakes of the Pyrenees, and about the effect of altitude on the species composition, and richness, of these communities. The investigation is addressed by analysing the relative relevance of the environmental and spatial components of the altitudinal gradient on macroinvertebrate communities. This is performed by comparing different macroinvertebrate groups, which attain for different evolutionary histories and ecological idiosyncrasies, including different dispersal capabilities. The taxonomical resolution achieved in macroinvertebrate determinations is high, which allows for among-group comparisons at the species level. These comparisons can be used to test ecological theories of current usage. Mountain lakes are particularly useful to this purpose, as these ecological systems account for large environmental gradients related to altitude and, at the same time, the altitudinal ecological gradient includes spatial components that may be relevant in shaping macroinvertebrate community assemblages. The spatial component of altitude relates to the uneven distribution of lakes along altitude in mountain ranges, which implies different degrees of ecological isolation between lakes. Also, the littoral zone of mountain lakes is particularly suited for among-group comparisons because it is in the littoral zone where most freshwater macroinvertebrate biodiversity of lakes concentrates. In the Results section, the results obtained are presented first as a general overview of the distribution of main macroinvertebrate taxa across altitude. The influence of environmental variables related to altitude on distributions is explored, and the relative relevance of different environmental variables on macroinvertebrate communities is partialled out. Then, the effect of different environmental and spatial factors is analysed for each macroinvertebrate group, separately. The main taxa analysed in each of the chapters are, arranged by convenience, as follows: Oligochaeta, Chironomidae, Mollusca, Megaloptera, Trichoptera, Coleoptera, Hydracarina and Nematoda. In the Discussion section, altitudinal distributions are compared between groups, and differences observed in this regard between the main macroinvertebrate taxa are discussed. The effect of both environmental and spatial factors related to altitude is suggested. Then, species richness patterns are also compared between the main macroinvertebrate taxa. The relative contribution of environmental and spatial factors is, to some extent, disentangled. Finally, the effect of altitude on the similarity of communities is also compared between groups, de-composing this effect in environmental and spatial terms. The following conclusions are drawn from the results obtained: 1) The altitudinal distribution patterns of lake macroinvertebrates are the consequence of both the selective influence of the environment and the more stochastic nature of dispersal. 2) Environmental factors covarying with altitude are not equally relevant for all macroinvertebrate groups. 3) Mountain lakes are biogeographic islands. 4) Similarity between communities is slightly higher, and stochasticity slightly lower, at mid altitudes. 5) The stochastic influence of environmental dynamics also contributes to explain species richness patterns. 6) Large river basins do not play a relevant role in the similarity of communities, which is more dependent on the altitudinal location of lakes. 7) An altitudinal ecological threshold in community assemblages occurs at ca. 2550 m a.s.l., for all groups responding to environmental changes across altitude, but independently of their dispersal strategy. 8) The altitudinal threshold, because of its environmental nature, is expected to shift upwards under current climate warming. 9) Global changes will affect macroinvertebrate communities of mountain lakes through different components, including climate warming, habitat loss and fragmentation, and invasive species, which may also show mutual interactions.
“Lake macroinvertebrates and the altitudinal gradient in the Pyrenees [Los macroinvertebrados lacustres y el gradiente altitudinal en los Pirineos]” es una tesis sobre las comunidades de macroinvertebrados acuáticos que habitan la zona litoral de los lagos de montaña de los Pirineos, y sobre el efecto de la altitud en la composición y riqueza de especies de estas comunidades. La investigación se efectúa analizando la importancia relativa de los componentes ambientales y espaciales del gradiente altitudinal sobre las comunidades de macroinvertebrados. Para ello, se comparan diferentes grupos de macroinvertebrados, de distinta idiosincrasia ecológica, incluyendo diferencias en cuanto a capacidad de dispersión. La resolución taxonómica con la que se analizan los datos es elevada, lo cual permite comparaciones entre grupos a nivel de especie, útiles para contrastar teorías ecológicas de uso actual. Las conclusiones de la tesis son las siguientes: 1) Los patrones de distribución altitudinal de los macroinvertebrados lacustres son consecuencia tanto de la influencia selectiva del ambiente, como de la dispersión, un proceso de naturaleza más estocástica. 2) Los distintos factores ambientales que covarían con la altitud no son igualmente relevantes para todos los grupos de macroinvertebrados. 3) Los lagos de montaña son islas biogeográficas. 4) La similaridad entre las comunidades es ligeramente mayor, y la estocasticidad en el ensamblaje de las mismas ligeramente menor, en altitudes intermedias. 5) La influencia de la dinámica estocástica del ambiente también contribuye a explicar los patrones de riqueza de especies. 6) Las cuencas de los ríos principales no juegan un papel relevante en la similaridad de las comunidades, que es más dependiente de la altitud de los lagos. 7) Existe un umbral ecológico para las comunidades de macro-invertebrados, situado a una altitud aproximada de 2550 m, que afecta a todos los grupos que responden a los cambios ambientales asociados a la altitud, pero con independencia de su estrategia de dispersión. 8) El umbral altitudinal, debido a su naturaleza ambiental, posiblemente se desplazará hacia arriba en altitud con el cambio climático actual. 9) El cambio global afectará a las comunidades de macroinvertebrados de los lagos de montaña a través de varios de sus componentes, incluyendo cambio climático, pérdida y fragmentación de hábitat, y especies invasoras, los cuales pueden mostrar también efectos de interacción mutua.

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Garey, Andrew L. "The Effects of Hydropeaking on Lotic Benthic Macroinvertebrate Assemblages." VCU Scholars Compass, 2015. http://scholarscompass.vcu.edu/etd/4057.

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The term hydropeaking refers to anthropogenically induced, short-duration, high-magnitude discharge pulses that are generated in lotic systems for electricity production. The practice of hydropeaking produces the largest source of renewable energy worldwide, and its use is projected to increase through the year 2040. The primary objective of this work was to evaluate the effects of hydropeaking on benthic macroinvertebrate assemblages, which are important components of lotic ecosystems. Results of this work show that, across a wide range of impacted systems worldwide, the consistently observed patterns of elevated benthic macroinvertebrate drift in response to hydropeaking pulses are primarily related to the rate at which discharge is increased (i.e., ramping rate) and secondarily to the time between pulses. In addition, it was shown that taxa inhabiting depositional habitat patches (i.e. fine substrates and slow water velocities) were most susceptible to peaking-induced drift, and that these taxa were also those most prevalent in hydropeaking-impacted systems. Collectively, these results suggest that increased pulse ramping rate and the resulting elevated macroinvertebrate drift may be positive selective forces, which benefit populations adapted for life in hydropeaking-impacted lotic ecosystems. These results provide a greater understanding of the factors that are most important for governing the effects of hydropeaking on benthic assemblages.

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Thoresson, Joakim. "Effects of a fish farm on downstream macroinvertebrates." Thesis, Umeå universitet, Institutionen för ekologi, miljö och geovetenskap, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-150565.

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The number of fish farms is increasing worldwide tomeet the global demand for fish used as a food source for humans. The WorldBank predicts that by 2030, 62 percent of all consumed fish globally will beproduced in fish farms. Due to this increasing demand for fish, fish farming isa growing business and the numbers of fish farms are increasing. Today, thereare fish farms situated in more than one hundred municipalities in rural partsof Sweden. Fish farms may besituated in hydropower plant reservoirs, which have been foundto be suitable locations for cage fish farming. However, environmental concernshave been raised regarding excess dissolved nutrients from fish farms thatmight enrich downstream ecosystems. The source of this enrichment is primarilyfish feces and uneaten fish feed, which contain both nitrogen and phosphorus. The overall objective of this study is to evaluate the effects of a largefish farm located in north-central Sweden on the downstream river ecosystem. Todo this, I compared benthic macroinvertebrate diversity, functional feedinggroup representation, community composition, and indices of biotic integritybetween a site downstream of a fish farm and a nearby (control) reach withoutan upstream fish farm. No significant difference between these sites wasobserved for any metric accept for the species richness, but due to the lowreplication results should be interpreted with caution. Further studies areneeded to assess the possible impact of fish farms on the water quality andecological health of rivers.

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Gabel, Friederike. "Impacts of ship-induced waves on benthic macroinvertebrates." Doctoral thesis, Humboldt-Universität zu Berlin, Landwirtschaftlich-Gärtnerische Fakultät, 2012. http://dx.doi.org/10.18452/16498.

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Schifffahrt stellt weltweit eine der wichtigsten Nutzungen der Flüsse und Seen dar, die zukünftig weiter zu nimmt. Sie schädigt Ufer durch Wellenschlag erheblich. Die Effekte von Schiffswellen auf benthische Wirbellose sind aber bisher kaum bekannt, obwohl diese eine zentrale Rolle im litoralen Nahrungsnetz spielen. Daher untersuchte ich 1) die direkten Effekte von Schiffswellen auf benthische Wirbellose, 2) die resultierenden Auswirkungen auf trophische Interaktionen und 3) das Wachstum und die Fitness von Wirbellosen, sowie 4) die langfristigen Änderungen der litoralen Wirbellosenzönosen. Labor- und Feldversuche zeigten, dass mit zunehmender wellengenerierter Sohlschubspannung mehr Individuen verdriftet wurden. Die Verdriftung wurde jedoch durch eine hohe strukturelle Habitatkomplexität gemindert, da diese die Wellenenergie stärker dissipierte und den Wirbellosen bessere Festhaltemöglichkeiten bot. Die Verdriftung der Wirbellosen bewirkte ein höheres Prädationsrisiko durch spindelförmige Fische, während hochrückige Fische die Ingestion bei Wellenexposition reduzierten. Wellenschlag verringerte auch das Wachstum und die Fitness nativer Wirbellosenarten, indem die Ingestion verringert oder der Energieverbrauch erhöht wurde, wohingegen Neozoen nicht beeinträchtigt wurden. Der kumulative Effekt von Schiffswellen veränderte die Artenzusammensetzung benthischer Zönosen sehr. Die Abundanz nativer Wirbelloser und die Artenzahl waren an exponierten Ufern geringer, während die Abundanz invasiver Arten zunahm. Folglich beeinträchtigen Schiffswellen benthische Wirbellose auf der Ebene der Individuen, Arten, Zönosen, sowie tropischer Interaktionen, und können so die ökologische Struktur und Funktion des gesamten Litorals beeinflussen. Durch Schutz komplexer Habitate wie Wurzeln und dichte Schilfbestände, sowie durch Wellenschlagsreduzierung durch größere Mindestabstände zum Ufer und angepasste Fahrtgeschwindigkeit, können die Auswirkungen von Schiffswellen gemindert werden.
Inland navigation is a major human use of rivers and lakes worldwide which is expected to increase in the future. It significantly affects shore habitats by ship-induced waves. In contrast to the importance of such pressures, the effects of these hydrodynamic disturbances on benthic invertebrates in the littoral zones are poorly understood, even that invertebrates are a central element of littoral food webs. Hence, I investigated 1) the direct and immediate effects of ship-waves on benthic invertebrates, 2) their subsequent effects on trophic interactions and 3) on the growth and fitness of invertebrates, and finally 4) the long-term effects on the community composition. Laboratory and field experiments showed increasing detachment of invertebrates with higher wave-induced shear stress. Detachment was significantly mitigated by higher structural complexity of the habitats, as complex habitats dissipate wave energy and provide better fixing possibilities. Moreover dislodgement of invertebrates led to a higher risk of being preyed upon by fusiform fish, while deep bodied fish reduced feeding under waves. Waves also reduced growth and fitness of native invertebrates via reduced feeding or increased energy costs, while non-native invertebrates were not affected. The cumulative impact of ship-waves alters the community composition of benthic invertebrates. The abundance of native invertebrates and total species richness was lower at exposed sites, while non-native invertebrates increased in abundance. Thus, ship-waves affect benthic invertebrates on the individual, species, and community levels, as well as the interaction of trophic levels, and hence will alter the ecological structure and function of whole littoral zones. Adverse effects of ship-waves may be mitigated by protecting structural complex habitats such as tree roots and dense reed belts, and by minimizing wave generation by increasing minimum sailing distance to shore or by adjusting vessel speed.

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Lee, David George. "Environmental change and freshwater macroinvertebrates at Wicken Fen, Cambridgeshire." Thesis, University of Cambridge, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.254522.

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Drummond, Laura Rose. "Influence of habitat drying on New Zealand stream macroinvertebrates." Thesis, University of Canterbury. School of Biological Sciences, 2011. http://hdl.handle.net/10092/6471.

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A better understanding of the responses by stream macroinvertebrates to habitat drying is needed as the pressure put on freshwater resources and hydrological regimes through land-use change, groundwater takes, and irrigation increases. To further understand the influences of abiotic and biotic factors on macroinvertebrate emergence, development, and mortality during habitat drying, I designed a field study and a mesocosm experiment. Three distinct drying regimes were measured in scour pools in the Selwyn River, Canterbury, New Zealand, over the austral summer of 2008/09. Pool hydroperiod (time from pool disconnection to drying) restricted the number of macroinvertebrate individuals that escaped desiccation. Fast, flexible development and multiple generations per year were more important invertebrate life history traits than metamorphosis type, with the highest emergence rates found in Diptera, and very low emergence rates in Trichoptera, both of which undergo complex metamorphosis. Emergence rates of Ephemeroptera, which undergoes less complex metamorphosis, decreased as water levels declined, indicating time restrictions were too great for a response to rapid drying. To further study the responses of macroinvertebrates with differing life history development (Deleatidium spp., hemimetabolous life history, and Olinga feredayi, holometabolous life history) to biotic and abiotic factors occurring during habitat drying, responses of macroinvertebrates to the three drying speeds, in the presence and absence of predator cues, were assessed in a mesocosm experiment. Total emergence of Deleatidium spp. was highest in slow-dry mesocosms with scent cues from predatory bullies present, and a three-way interaction was present between flow treatment, predator treatment, and time, in daily Deleatidium spp. emergence rates. Olinga feredayi had no emergence in any treatment but their survival was highest, possibly due to a trade-off between predation resistance and flexible life history. Thus responses by macroinvertebrates were highest in the highest risk situation, and were dependent on lifecycle type allowing rapid development in a highly time constrained habitat.

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O'Hare, Matthew Thomas. "Flow preferences of benthic macroinvertebrates in three Scottish rivers." Thesis, University of Glasgow, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.312705.

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Landström, Emelie. "Resource use by macroinvertebrates within boreal stream food webs." Thesis, Umeå universitet, Institutionen för ekologi, miljö och geovetenskap, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-105593.

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Stream food webs are supported by carbon produced within the stream (autochthonous) and from terrestrial environments (allochthonous). Allochthonous carbon (C) inputs are assumed to be the dominant C source supporting food webs within small streams, but few direct estimates of resource use in small streams have been made, especially in boreal streams. The objective of this study was to determine the relative dependence on allochthonous and autochthonous C by consumers in relation to C pools within streams with high terrestrial inputs. Furthermore, this study aimed to investigate if the relative resource use of allochthonous and autochthonous C by consumers differed among seasons (summer and fall), between streams of different sizes, and locations within the catchment. To estimate consumer resource use, δ2H signatures for organic C sources were compared to those of six key consumers in five streams of varying catchment sizes in northern Sweden. Macroinvertebrate biomass was quantified to calculate a taxa-specific biomass-weighted allochthony, and compared with the mass of different C pools potentially available for consumers. The biomass-weighted mean allochthony for all samplings ranged between 43.5-61.5%; there was thus high autochthonous support despite low algal density and high terrestrial C pools within the streams. No significant trend in allochthony was observed over season (linear regression, p-value >0.05). Allochthony differed by invertebrate taxa and was not related to stream size or location in catchment. These results suggest that autochthonous C is far more important for consumers in boreal streams than previously recognized.

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Mendes, Tânia Marisa Neves. "Combined assessment of streams based on diatoms and macroinvertebrates." Master's thesis, Universidade de Aveiro, 2012. http://hdl.handle.net/10773/9527.

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Mestrado em Ecologia, Biodiversidade e Gestão de Ecosistemas
As diatomáceas e os macroinvertebrados fornecem informação complementar na avaliação da qualidade da água. No entanto, os métodos utilizados para esse fim têm sido desenvolvidos separadamente para as duas comunidades. O objetivo deste estudo foi verificar se um modelo preditivo baseado nos dois elementos biológicos produz uma avaliação mais simplista e simultaneamente mais holística e robusta da qualidade dos ecossistemas face aos métodos individuais, os quais necessitam de ser combinados posteriormente, usualmente com base na abordagem “one-out al-out”. Para tal, foram utilizados dois métodos, RIVPACS e BEAST, devido às suas diferentes características, especialmente porque o RIVPACS utiliza dados de presença/ausência enquanto o BEAST utiliza dados de abundância. Foram construídos 6 modelos preditivos para o território português: dois para as diatomáceas, dois para os macroinvertebrados e dois integrando as duas comunidades. Nas primaveras de 2004 e 2005 foram simultaneamente amostradas diatomáceas e macroinvertebrados de 143 locais minimamente perturbados. Foram selecionados 23 locais afetados por contaminação orgânica, efluentes industriais e minas do centro de Portugal para serem utilizados como locais teste. O modelo RIV INV+DIAT atribuiu a mesma classe de qualidade do que o método “one-out all-out” a cerca de 70% dos locais teste, enquanto o BEAST INV+DIAT apenas partilhou cerca de 40% dos locais com a mesma classe. As respostas dos diferentes métodos (incluindo o “one-out all-out”) à degradação ambiental foram avaliadas através de correlações de Spearman. Apesar do RIVPACS ser menos sensível do que o BEAST, demonstrou funcionar melhor quando se combinam as duas comunidades. O tipo de dados influenciou a avaliação dos dois métodos demonstrando ser apenas fiável integrar as diatomáceas e os macroinvertebrados num único método usando dados de presença/ausência.
Diatoms and macroinvertebrates provide complementary information on stream water quality. However, classification methods have been developed separately for the two biological elements. The aim of the present study was to assess if a predictive model based on the evaluation of biodiversity using taxa from both biological elements, produces a simpler and simultaneously more holistic and accurate assessment of stream health than individual methods. These classifications need to be combined later, usually based on “one-out all-out” approach. For that purpose, two different approaches were used, BEAST and RIVPACS, due to their different characteristics, mostly because RIVPACS uses presence/absence data while BEAST uses abundance. Six predictive models were built for the entire Portuguese territory: two for diatoms, two for macroinvertebrates and two combining diatom and macroinvertebrate communities. Data from 143 minimally disturbed sites sampled simultaneously for diatoms and invertebrates in the spring of 2004 and 2005 were used to calibrate and validate the models. For all the six predictive models, 23 impacted streams from central Portugal affected by organic contamination, industrial effluents and mine drainage were used as test sites. The RIV INV+DIAT model shared with “one-out all-out” approach about 70% of the test sites with the same quality class while the BEAST INV+DIAT model only shared about 40%. The responses to the environmental degradation of the different approaches (including the “one-out all-out”) were analyzed through a Spearman correlation. In spite of the less sensitive RIVPACS approach results in comparison to BEAST, it showed to work better when the two biological elements were joined. The type of data influenced the assessment of the two approaches and diatoms and macroinvertebrates can be integrated reliably into a single method using only the presence/absence type of data.

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Jakobsson, Ellinor. "Seasonal community dynamics of macroinvertebrates in an Arctic stream." Thesis, Umeå universitet, Institutionen för ekologi, miljö och geovetenskap, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-160186.

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Arctic ecosystems are amongst the most vulnerable on Earth to ongoing climate change. While the responses to these changes are well studied on land, less is known about how aquatic communities may respond to a warmer arctic. For stream invertebrate communities, predicting such responses requires basic understanding of how and why different taxonomic groups fluctuate throughout the year. However, few studies have assessed the community dynamics of stream macroinvertebrates across seasons in the Arctic. In this project, I asked how macroinvertebrate community structure changes between months and across seasons in a small Arctic stream in northern Sweden. I expected that community change over time would reflect changes in the supply of organic matter (e.g., leaf litter and algae) to dominant consumers. A total of five transects were sampled for macroinvertebrates each month from July to April using Surber sampling. I used descriptive and multivariate analyses to evaluate changes in community structure between months and seasons. Marked differences in community composition were found between the seasons with detritivores (shredders) dominating the autumn months possibly reflecting input of birch litter and high abundances of grazers during and post winter, possibly reflecting primary production early in spring. Expected climate change effects in the Arctic include warmer temperatures and increases in the terrestrial plant productivity. My results suggest that these shifts could cause changes in stream community composition, driven by increases in deciduous litter inputs that promote shredders and/or by increases in primary production during spring that favour grazers and collector-gatherers, which feed on algae.

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Song, Mi-Young. "Ecological quality assessment of stream ecosystems using benthic macroinvertebrates." Toulouse 3, 2007. http://thesesups.ups-tlse.fr/224/.

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Dans cette étude, nous avons appliqué le modèle SOM (Self-Organizing Map) pour une évaluation de la qualité écologique de l'écosystème aquatique en se basant sur les macroinvertébrés benthiques. D'abord, dans le chapitre I, le SOM a été utilisé pour extraire les informations à partir de grandes matrices de données complexes de variables environnementales et des macroinvertébrés benthiques des différents microhabitats. Bien que les échantillonnages aient e��té réalisés dans une zone limitée, le patron des variables environnementales révèle une hétérogénéité spatiale. Les classes de macroinvertébrés dans le modèle SOM ont montré une variation temporelle et permettent l'évaluation de la qualité de l'eau en accord avec les conditions des différents microhabitats. En conséquence, l'hétérogénéité spatiale locale est importante en révélant les dynamiques des communautés et les indices biotiques, particulièrement en rapport avec le processus de restauration des rivières polluées. Dans le chapitre II, les échantillons ont été classés en 3 groupes principaux par le modèle SOM pour distinguer les assemblages EPTC (Ephéméroptères, Plécoptères, Trichoptères, Coléoptères) dans les cours d'eaux du Coteau de Gascogne, tributaires de la Garonne (sud-ouest France). Des faibles richesses et diversités ont été observées dans cette zone affectée par une pratique agricole intensive, caractérisée par de très fortes valeurs de TDS (Total Dissolved Solids), nitrate (NO3) et COD (Chemical Oxygen Demand). Les espèces EPTC tolérantes ont été utilisées comme paramètres de contrôle pour les changements d'assemblage de communautés collectées dans des sites impactés par la pratique agricole. .
In this study, we applied the SOM for ecological assessment using benthic macroinvertebrates in aquatic ecosystem. First, Chapter I, SOM was utilized to extract information from complex data of environmental variables and benthic macroinvertebrate communities residing in different micro-habitats. Although the sampling was carried out in a limited area, the patterns of environmental variables revealed spatial heterogeneity. The clustering of benthic macroinvertebrate communities in the trained SOM was efficient in showing temporal variation and evaluating water quality according to the conditions of different micro-habitats. Consequently, local spatial heterogeneity is important in revealing dynamics of community abundance and biotic indices, especially regarding restoration processes in polluted streams. Chapter II, the samples were grouped into three main clusters corresponding to distinc EPTC assemblages in the tributary streams of the Garonne River catchment, southern France. Lower richness and diversity of macroinvertebrates were observed in the areas affected by agricultural land use, being associated with high Total Dissolved Solids (TDS), Nitrate (NO3) and Chemical Oxygen Demand (COD). Tolerant EPTC species were identified as controlling parameters for the changes in the assemblages collected at the agricultural-impacted sites. .

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Câmara, Carla Daniela. "Critérios e indicadores para monitoramento hidrológico de florestas plantadas." Universidade de São Paulo, 2004. http://www.teses.usp.br/teses/disponiveis/18/18138/tde-12052006-111320/.

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O presente estudo propôs uma nova leitura dos dados do monitoramento hidrológico de sete microbacias experimentais, considerando que as variáveis que caracterizam os sistemas aquáticos destas microbacias constituem indicadores da qualidade do manejo florestal. Os objetivos do estudo foram: a) selecionar, entre as variáveis já monitoradas, os potenciais indicadores para o monitoramento hidrológico de florestas plantadas; b) testar a viabilidade da utilização da comunidade de macroinvertebrados bentônicos como indicador biológico. O estudo foi desenvolvido nas seguintes microbacias: na região do Município de Guaíba, RS, uma com floresta plantada e uma com pastagem; em Itatinga, SP, uma com floresta plantada; em Alagoinhas, BA, uma com floresta plantada e três em Imperatriz, MA, uma com floresta nativa, uma com floresta plantada de eucalipto e uma com pastagem. O estudo consistiu na análise de dados da medição contínua da vazão, da precipitação e de variáveis físicas e químicas da água dos córregos das microbacias durante diferentes períodos e também no estudo da comunidade de macroinvertebrados bentônicos por um período de um ano. Como resultado, foram selecionadas, para o início de um programa de monitoramento de florestas plantadas na escala da microbacia hidrográfica, 12 indicadores que atendem a três critérios. São eles: 1 - manutenção dos processos hidrológicos da microbacia e da qualidade das operações florestais com os indicadores balanço hídrico, picos de vazão, sólidos em suspensão, turbidez, condutividade elétrica, fósforo, oxigênio dissolvido, potássio, temperatura da água e macroinvertebrados bentônicos; 2 - manutenção do potencial produtivo do solo com os indicadores fósforo, nitrogênio, cálcio, potássio, magnésio, e sólidos em suspensão, e 3 - manutenção do equilíbrio dinâmico do ecossistema aquático, com os indicadores oxigênio dissolvido, fósforo, nitrogênio, temperatura da água, sólidos em suspensão, pH e macroinvertebrados bentônicos
This study proposes a new analysis of data from hydrological monitoring of seven experimental catchments considering that the monitored hydrological variables can be used as indicators for forest management quality. The objectives of the study were: a) select, among the monitored variables potential indicators for the hydrological monitoring of planted forests; b) investigate weather macroinvertebrate community can be used as biological variable. The study was carried out in catchments covered by Eucalyptus forests located in the Municipalities of Guaíba, State of Rio Grande do Sul, Itatinga, State of São Paulo, Alagoinhas, State of Bahia and Imperatriz, State of Maranhão; catchment covered by native forests in the Municipality of Imperatriz State of Maranhão and catchments used as pastureland in the Municipalities of Guaíba, State of Rio Grande do Sul and Imperatriz, State of Maranhão. The study involved data analysis of precipitation, streamflow and water quality variables measured during different periods and the study of the macroinvertebrate community during one-year period. As a result, 12 variables according to 3 criteria of forest sustainable management were selected. The criteria and indicators are the following: 1 - maintenance of catchment hydrologycal processes and forest management quality, for which the indicators are water balance, peak flow, suspended solids, turbidity, conductivity, phosphorus, dissolved oxygen, potassium, water temperature and benthic macroinvertebrate community; 2 maintenance of soil productivity, with the indicators phosphorus, nitrogen, calcium, potassium, magnesium, and suspended solids, and the third criteria, maintenance of the dynamic equilibrium of aquatic ecosystem, with the indicators dissolved oxygen, phosphorus, nitrogen, water temperature, suspended solids, pH, and benthic macroinvertebrate community

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Beghelli, Frederico Guilherme de Souza [UNESP]. "As relações de organismos bentônicos bioindicadores com a poluição por metais e metaloides em represas do sistema Cantareira, São Paulo." Universidade Estadual Paulista (UNESP), 2016. http://hdl.handle.net/11449/140278.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Vivemos atualmente, um cenário de crise hídrica mundial. Tal crise inclui tanto aspectos quantitativos quanto qualitativos ameaçando a segurança hídrica das sociedades humanas e os ecossistemas do planeta Terra. No Brasil, a região hidrográfica do Paraná destaca-se como região com maior densidade populacional, desenvolvimento econômico e industrial do país sendo, portanto, a região com maior demanda pelo recurso. No Estado de São Paulo desenha-se uma situação de crise hídrica agravada em ambos os aspectos. Do ponto de vista qualitativo, a Região Metropolitana de São Paulo destaca-se como aquela cujos mananciais encontram-se em situação mais impactada. O Sistema Cantareira, composto por um conjunto de cinco reservatórios é um dos principais sistemas fornecedores de água para esta região de intensas demandas e geradora de grandes impactos ambientais. A poluição de ambientes aquáticos por metais e metaloides é um problema mundial e frequentemente associado aos impactos gerados por regiões urbanas e industrializadas. Um agravante deste tipo de poluição, é o fato de os metais e metaloides não serem metabolizados pela biota, de forma que estes elementos tendem a se acumular, especialmente nos sedimentos, ao longo do tempo, com possibilidade de poluição das águas e dos organismos que habitam os ecossistemas aquáticos. Neste estudo, foram levantados dados referentes a qualidade da água e dos sedimentos de três reservatórios pertencentes ao Sistema Cantareira (Jaguari e Jacareí sendo consideradas como um único reservatório). Posteriormente, foram realizados estudos da fauna de macroinvertebrados bentônicos destes locais e experimentos com o intuito de se verificarem as respostas destes organismos à poluição das águas e sedimentos por metais e metaloides. Os resultados obtidos, indicaram poluição das águas e dos sedimentos destes reservatórios por diferentes elementos químicos (Al, Cd, Cr, Cu, Ni, Pb e Zn). Foi verificado, com dados de campo e testes estatísticos, que alterações morfológicas em larvas de Chironomidae variavam em função do aumento das concentrações de cobre nos sedimentos e que estas concentrações eram suficientes para provocar bioacumulação nos organismos. Posteriormente, demonstrou-se com um experimento in situ, que os sedimentos do reservatório Paiva Castro estavam poluídos e foram capazes de induzir efeitos letais e subletais em larvas de Chironomus sancticaroli. A realização de um experimento similar em laboratório e com sedimentos formulados resultou na conclusão de que as concentrações de cobre nos sedimentos, de fato induzem efeitos tóxicos sobre as larvas desta espécie, incluindo o aumento de “danos totais” (alterações morfológicas ou morte) a concentrações próximas às registradas no Paiva Castro. Por fim, utilizando-se modelos estatísticos e o conjunto de dados obtidos em campo, foi possível demonstrar os efeitos da toxicidade de diferentes metais (Al, Cr e Cu) em nível de comunidade, fornecendo-se as bases para o desenvolvimento de um índice da comunidade de macroinvertebrados bentônicos específico para poluição por metais para a região de estudo.
A global water crisis is in course. This crisis include quantitative and qualitative aspects and it threatens the water security of human societies and of the Earth’s ecosystems. In Brazil, the Paraná hydrographic region is the one with highest population density, economic and industrial development. As consequence, it is the hydrographic region in Brazil that demands highest amounts of water. São Paulo state is suffering the effects of the hydrological crisis. Qualitatively, the Metropolitan Region of São Paulo includes some of the most impaired aquatic environments. The Cantareira Complex is formed by five reservoirs. It is one of the main water suppliers of the region, which has high water demand and produces intensive environmental impairments. The pollution of aquatic environments by metals and metalloids is a worldwide problem and it is frequently related to the impairments generated in urban and industrialized regions. A problem related with this type of pollution is the fact that metals and metalloids are not metabolized by biota. As consequence, these chemicals have the tendency to accumulate through the time in the environment, especially in the sediments. Therefore, the pollution of the sediments can favor water pollution and the contamination of organisms living in aquatic ecosystems. In the present research, data referring to water and sediment quality from three reservoirs from Cantareira Complex (Jaguari and Jacareí were considered as a whole) were obtained. Posteriorly, the benthic macroinvertebrates fauna from those reservoirs were analyzed in order to verify the impacts of metal pollution over them. Experiments aiming to verify the responses of these organisms to sediment pollution by metals, especially copper were performed. The results points that water and sediments of the reservoirs analyzed here are polluted by metals and metalloids (Al, Cd, Cr, Cu, Ni, Pb and Zn). From field data and statistical analyses, it could be concluded that morphological alterations in Chironomidae larvae varied as a response to copper concentration in the sediments and that the copper concentrations were sufficiently high to cause bioaccumulation in the organisms. Posteriorly, it was demonstrated by an in situ assay that sediments from Paiva Castro were really contaminated and them induced lethal and sublethal effects on Chironomus sancticaroli larvae. A similar experiment performed in laboratory with spiked sediments leads to the conclusion that the copper in the sediments really can produce toxic effects on the larvae. Toxic effects included an increasing in “total damage” probabilities (morphological alteration or death) and they were recorded at concentrations similar to that recorded in the sediments from Paiva Castro reservoir. Another analysis included the use of statistical models to predict response of the organisms collected in the field to the toxicity of metals considering the community level. With this last approach, some basis to the development of a benthic macroinvertebrates community index to the assessment of pollution by metals (Al, Cr e Cu) in the region of Cantareira Complex was provided.
FAPESP: 2013/03494-4

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Smith, Heidi. "The hydro-ecology of limestone springs in the Wye Valley, Derbyshire." Thesis, University of Huddersfield, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.327144.

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Skorupski, Joseph A. Jr. "Effects of CFT Legumine™ Rotenone on Macroinvertebrates in Four Drainages of Montana and New Mexico." Thesis, University of North Texas, 2011. https://digital.library.unt.edu/ark:/67531/metadc84278/.

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Rotenone is considered essential in the restoration of native fish populations; however, the technique is contentious and criticized, specifically concerning impacts to invertebrates. Knowledge of effects to non-target organisms is important for the management and conservation of fish populations. This thesis has two general objectives: (1) demonstrate the influence CFT Legumine™ rotenone has on benthic macroinvertebrates for restoration projects in Montana and New Mexico and (2) evaluate the immediate response by means of invertebrate drift. Chapters 2 and 4 incorporate results from four different restoration projects that examine benthic macroinvertebrate response. Results indicate treatment effects are minimal for Specimen and Cherry Creek projects in Montana. New Mexico projects, Comanche and Costilla Creek suggest a greater influence. Potassium permanganate used to neutralize rotenone, influenced communities in three of the four projects. Regardless, invertebrates in all four projects recovered one-year after treatment. Chapter 3 examines macroinvertebrate drift during rotenone treatment. Results suggest a delayed response compared to previous literature. Rotenone appears to have the greatest immediate influence on the early life stages of Ephemeroptera and Plecoptera. To reduce impacts of rotenone to invertebrates, managers should apply CFT Legumine and use the minimal dosage and duration to complete the projects goal of removing non-indigenous fish species.

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Vasconcelos, Márlon de Castro. "Efeito do sedimento fino de origem terrestre sobre a fauna de macroinvertebrados bentônicos em riachos." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2007. http://hdl.handle.net/10183/10908.

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O aporte de sedimento fino é um dos principais agentes causadores de impactos a ecossistemas aquáticos. Este trabalho teve por finalidade avaliar por experimentalmente o efeito do sedimento fino sobre a fauna de macroinvertebrados bentônicos em um riacho subtropical. O local escolhido foi o rio Forqueta no distrito de Barra do Ouro pertencente ao município de Maquiné, RS. Foi adicionado por tratamento cerca 3138 cm3 de sedimento fino, separado em duas frações: areia fina (0 mm a 0,250mm) e areia grossa (0,25 mm a 1mm), em dois níveis, com e sem sedimento. Os dados foram analisados através por meio de uma Análise de Variância (ANOVA) de dois fatores para abundância total, riqueza e riqueza rarefeita, além de uma Análise de Variância Multivariada (MANOVA) para abundância relativa e composição de espécies e de uma Análise de Correspondência Canônica (pCCA), esta última, para avaliar o quanto eventos de perturbações influenciam a fauna aquática. A interação entre a velocidade do fluxo e os fatores envolvendo sedimentos também foram avaliados. O sedimento fino afetou negativamente a abundância total, a riqueza e a composição de espécies, mas não a riqueza rarefeita e a abundância relativa.O fluxo foi um importante fator para a distribuição da fauna avaliada, sendo a abundância, riqueza e a riqueza rarefeita maior em áreas com maior fluxo. Houve interação do fluxo com a areia fina, aumentando seu efeito sobre a abundância total e riqueza rarefeita em locais com maior velocidade de fluxo. A pCCA mostrou que eventos pontuais e de curta duração de acréscimo de sedimento fino não são danosos à fauna aquática. Os resultados obtidos mostram que o sedimento fino afeta de forma negativa a fauna de macroinvertebrados bentônicos em riachos, e este efeito negativo se dá por diversas formas, tais como redução do hábitat, perda da qualidade do alimento, estresse fisiológico e por outros. A relação da fauna com a velocidade pode ser atribuída às preferênciasecológicas dos grupos encontrados. Por alguns resultados divergirem de estudos prévios, o efeito do sedimento fino sobre a fauna aquática deve ser mais bem estudado.
One of the main forms by which aquatic ecosystems are impacted is the input of fine sediment. The objective of our study was to determinate by one experiment the effect of fine sediment on benthic macroinvertebrates in subtropical streams. The study area was the Forqueta River in Barra do Ouro district of Maquiné city, Rio Grande do Sul, Brazil. It’s was added 3138 cm3 of sediment, in two fractions: fine sand (0mm – 0.25mm) and coarse sand (0.25mm – 1mm) into the river with two levels (with or without sediment) . The data were analyzed by Analysis of Variance (ANOVA two-way) for abundance, richness and rarefied richness, the last one intended to compare species richness based on an equivalent number of individuals. Using Multivaried Analysis of Variance (MANOVA) we examined the effect of fine sediment on relative abundance and composition of species. Sediment was used as one factor in four levels. A Partial Canonical Correspondence Analysis (pCCA) was used to examine the effect of the disturbance event on communities. The interaction between the flow and the factors of the sediment was examined. There was a negative effect of fine sediment on abundance, richness and species composition, but the effect was null on relative abundance and rarefaction of species richness. The flow was important for distribution of individuals colleted. The abundance, species richness and rarefied richness were highest on places with fastest flows. The flow increased the effect of fine sand on abundance and rarefied richness. The pCCA showed that disturbance events of small frequency consisting of input of terrestrial sediment have no negative effects on benthic macroinvertebrate. The relationship between flow and benthic macroinvertebrates can be attributed to the ecological preferences of species. These results showed that fine sediment impact is harmful for benthic macroinvertebrates in streams, particularly in termsof abundance. This negative effect may be a consequence of loss of habitat, reduced food quality, physiological stress and others forms. Because some results differ from other studies, the effect of the fine sediment on the benthic macroinvertebrates needs to be better studied.

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Oswald, Louisa Jane, and n/a. "Usefulness of Macroinvertebrates for In Situ Testing of Water Quality." University of Canberra. Institute for Applied Ecology, 2008. http://erl.canberra.edu.au./public/adt-AUC20090107.130047.

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For various reasons, existing methods for the assessment of aquatic pollution do not always adequately address the way in which contaminants affect receiving environments and their component ecosystems. The main advantage of biological assessment over the measurements of physical and chemical aspects of water quality is that biota provide an integrated response to all prevailing influences in their environment. Biological assessment protocols have been developed for a range of test organisms, from bacteria to mammals using measurement from molecular biomarkers to indicators at the population or community level of organisation. Macroinvertebrates in particular have been popular for ecological assessment of habitat and water quality because they are small and straight forward to sample and identify using relatively simple and inexpensive equipment and readily available taxonomic keys. However, various biological assessment techniques also have their limitations. Field-based assessment of biological communities does not provide direct evidence to determine underlying causal relationships, while laboratory or mesocosm toxicity tests are criticised for their limited ability to extrapolate to natural field conditions. To help bridge the gap, this thesis aims to investigate the efficacy of using caged macroinvertebrates in situ to assess the ecological condition of aquatic environments, and whether a causal relationship can be established when macroinvertebrates are deployed in situ at sites known to have impaired water quality. Endpoints employed in this thesis include survival, measurements of morphology (as a surrogate for growth) and condition and, for trials assessing sites that receive mine drainage, the tissue concentration of certain trace metals. Development of an in situ approach to water quality monitoring and assessment will potentially provide methods for use by resource managers, community groups and aquatic researchers that are less expensive and faster to run than existing methods and will complement other approaches employed in the assessment of water quality. In situ testing of water quality using macroinvertebrates requires the collection, handling, caging, deployment and retrieval of test organisms at sites of suspected pollutant impact. As such procedural factors may affect test organisms and potentially confound their responses, it is important to consider and understand as many of these factors as possible. Aquatic macroinvertebrates held in finer mesh cages had larger heads than in coarser mesh cages. This was likely due to increased substrate available for growth of epilithon and periphyton on which the caged organisms could graze. Caging density had no effect on amphipod mortality over the trial period, however, individuals held at higher densities increased in size (as indicated by longer dorsal lengths) more than those held at lower or intermediate densities. Temporary storage of test organisms in laboratory aquaria may facilitate the collection of abundances required for in situ trials, however, tanked individuals were smaller and had lower biomasses than individuals collected and deployed immediately. While this is likely to result from differences in feeding during the storage period, it is also possible that tank storage and the ?double handling? deleteriously affected them, or reduced their tolerance. The effects of transplanting macroinvertebrates between sites varied considerably depending on the characteristics of "source" and "transplant" sites. Certain taxa suffered marked mortality within 24 hours even at their source site, indicating an adverse effect of the caging itself, or perhaps via the change in food, shelter or microclimate which could potentially render them unsuitable as test organisms in caging studies. Other taxa did not differ in survival or body size when relocated between sites, with some evidence of increased growth at sites dissimilar from their source site. In general, organisms relocated to sites that are "similar" to their source environment performed less well at the transplant site. However, organisms transplanted to "dissimilar" sites were found to be bigger than those caged and deployed back to the source site. When employed to assess known pollution scenarios in and around Canberra, macroinvertebrate responses were, in some instances, able to be linked to specific environmental parameters or combinations thereof. In Case Study 1, findings varied in relation to the response endpoint being examined, and between test species, although concentrations of metals were significantly higher in tissue of macroinvertebrates deployed at the impact site downstream of the abandoned Captains Flat mine and increased with time exposed. In Case Study 2, freshwater shrimp suffered significant mortality within 24 hours of deployment at the impact sites, with larger individuals more susceptible at sites receiving urban stormwater runoff. While various biological effects were most closely correlated with ammonia concentrations at the site, different body size endpoints were affected in opposite ways. In Case Study 3, body size endpoints for one test organism varied consistently with respect to site and time factors, but none of the changes could be linked to any of the environmental data collected. Response variables for a different test species also indicated significant effects arising from both deployment site and time, however, each endpoint responded in a different way to the treatment factors, and aligned with different combinations of environmental data. In general, linking of macroinvertebrate responses with environmental data was difficult because of the high variability in the environmental data. However, it was further complicated by the mismatch in the level of replication between the two datasets. As a consequence of this, the macroinvertebrate data had to be collapsed to a lower level for comparison with the environmental data, resulting in a loss of natural variability and analytical power. Since only the strongest treatment effects, which could be detected above the background "noise", were detected and modelled against the environmental data, it is possible that other "cause" and "effect" relationships may have been overlooked. From these results, it is clear that many macroinvertebrate taxa are suitable for use as bioindicators in in situ trials, but that criteria used for selection of test species should definitely include more than just impact-sensitivity and abundance. However, there are several aspects associated with the experimental set up of field-based protocols involving caged macroinvertebrates that may limit their usefulness as a rapid and reliable bioassessment tool, and need to be considered when designing and undertaking these kinds of trials. It is also apparent that choice of endpoint can greatly influence conclusions, with detection of treatment effects reported in this thesis varying greatly depending on which morphological endpoint was examined. This study clearly demonstrated that there may be significant difficulties in establishing causal relationships between environmental data and biotic responses of macroinvertebrates deployed under field conditions. However, it has also shown that deployment of caged macroinvertebrates in situ may assist in the determination of biological effects arising from impaired water quality, which can then serve as the basis for more focussed laboratory or mesocosm studies in which environmental conditions can be more readily controlled or monitored.

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25

Edwards, Patrick Michael. "Macroinvertebrates and Excessive Fine Sediment Conditions in Oregon Coastal Streams." Thesis, Portland State University, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3629266.

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The Pacific Coastal ecoregion contains large tracts of economically important forestlands that also serve as critical stream habitat for endangered Salmonids. Excessive fine sediment deposition in streams of this region is a major environmental concern in the region but difficult to measure directly. The use of stream invertebrates to monitor fine sediment conditions in streams requires careful consideration of several important factors that complicate their use as bioindicators including high spatial and temporal variability and covariance with other environmental variables.

To evaluate the use of stream invertebrates as bioindicators of excessive fine sediment, three hypotheses were tested. The first hypothesis was that invertebrates would be related to broad-scale climate variables (Chapter 2). The second hypothesis was that functional aspects of the invertebrate community would serve as useful indicators of excessive fine sediment condition. (Chapter 3). The third hypothesis was that invertebrates in streams with naturally high levels of sediment would be tolerant to fine sediment (<2 mm, Chapter 4). Hypotheses were tested using a temporal data set at two streams in western Oregon, spatial data from 214 sites across the Oregon Coast Range, and in-situ experiment conducted in streams with erosive or resistant geologies.

In the temporal study, both invertebrate density and functional traits were positively related to El Niño strength (R² range = 0.22–0.36, ρ range = 0.008–0.04) and air temperature (R² range = 0.32–0.49, ρ range = 0.002–0.01). The spatial study identified several environmental and hydrological factors that exhibited strong negative controls on both fine sediment (Mantel r range 0.14–0.25, ρ range = 0.001–0.01) and invertebrate Scrapers (R² range = 0.11–0.14, ρ range = 0.001–0.04). The result of the experimental study provide evidence that invertebrates in streams with erosive geologies exhibit tolerance to sediment addition when compared to invertebrates in resistant geologies (mean loss=15%, ρ <0.01) and that invertebrate grazing traits were most strongly associated with fine sediment dosing frequency (ρ <0.05).

The findings of this research demonstrate the role of geology in shaping invertebrate communities and their functional response to fine sediment addition and identify functional indicators that may be useful in different geologic settings. For environmental managers in the Pacific Coastal ecoregion, these findings are of potential value in assisting with the identification of biologically-relevant changes in stream fine sediment conditions and support efforts to balance economic needs in the region while protecting critical Salmonid habitat.

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26

Foster, Carole A. "Benthic macroinvertebrates in Uvas Creek, California, downstream of a reservoir." Thesis, San Jose State University, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=1583489.

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I sampled macroinvertebrates in May, July, and October 2008 in Uvas Creek, a reservoir-regulated stream in south Santa Clara County, California, to assess what factors (including canopy closure, turbidity, and stream flow) downstream of the reservoir were related to food availability for rearing juvenile Steelhead (Oncorhynchus mykiss). I found benthic and drifting macroinvertebrate biomass was considerably greater during most months in the more open-canopied two sites in the downstream reach as compared to the densely shaded, more turbid and silty two sites in the upstream reach. Abundance of important drifting aquatic invertebrates in May (chironomids, simuliids, and baetids) was proportional to benthic abundance, but large hydropsychids were relatively scarce in the drift. Terrestrial drift abundance correlated with canopy density, but differences were small compared to the substantial increase in aquatic drift in sunnier sites. Thinning of the canopy at select locations and reduction of sediment input to Uvas Creek and its tributaries due to vineyard and other operations could increase benthic macroinvertebrate productivity in the upstream reach, which would increase food availability for rearing juvenile Steelhead.

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27

Kelly, Lucy Claire. "Community ecology and genetics of macroinvertebrates in permanent Macaronesian streams." Thesis, University of Plymouth, 2001. http://hdl.handle.net/10026.1/738.

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Extensive community-based sampling and single-species genetic analysis were used to study factors driving stream invertebrate community assembly on islands. Macroinvertebrates and physicochemistry were surveyed in forty-two streams on La Palma, La Gomera, Tenerife and Madeira (Macaronesia). Island faunal relationships and the role of the stream and catchment environment in determining community composition were investigated with multivariate analyses; assemblage nestedness and species richness, occupancy and abundance were also examined. The relationship between genetic differentiation and range size was tested using allozyme variation in selected species. Island species pools differed in community composition and species richness (total, and endemic), broadly as predicted by theory of island biogeography. Stream and island species richness were correlated, showing unsaturated, possibly dispersal-limited, communities, and stream faunas were nested, evidence that assemblages were not random (e.g. only generalist/dispersive taxa occur at species-poor sites). Endemics occurred in more streams than non-endemics, suggesting greater habitat availability for the former, but similar niche width, endemic and non-endemics having similar local abundance. Species richness, community composition and the abundances of individual species were correlated with stream physicochemistry, itself reflecting geology, rainfall, altitudinal zonation of vegetation and the intensity of stream exploitation. Allozyme variation was surveyed in Mesophylax aspersus (Trichoptera: Limnephilidae) and Wormaldia tagananana (Trichoptera: Philopotamidae), respectively having widespread and localised distributions. Population structure supported the hypothesis that range size is, at least partly, limited by poor dispersal ability in W tagananana. Genetic variation in Ancylus striatus (Gastropoda: Ancylidae) was typical of polyploidy and selffertilisation/ parthenogenesis. Breeding system has consequences for a species' colonisation ability, and may partially explain the wide distribution of A. striatus within the islands. Variation in community composition reflected patterns at a range of scales. Biogeography detennined the island species pooL whilst local physicochemistry determined richness and community composition within islands. Species characteristics that affect their colonisation and c:\tinction probabilities (e.g. habitat selection at the local- and mesoscaks, dispersal patterns and breeding system). influence hoth the local and regional species pools.

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28

Mustow, Stephen Eric. "Aquatic macroinvertebrates and environmental quality in rivers in Northern Thailand." Thesis, University of London, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.266399.

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29

Roberts, Louise. "Behavioural responses by marine fishes and macroinvertebrates to underwater noise." Thesis, University of Hull, 2015. http://hydra.hull.ac.uk/resources/hull:11515.

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The aim of this thesis was to explore and evaluate the key behavioural responses of coastal UK marine fishes and macroinvertebrates to anthropogenic noise. Work focussed upon two key aspects, water-borne acoustics and the relatively unstudied substrate-borne vibration, with a combination of laboratory and field work using grouped and solitary individuals. A literature review on underwater vibroacoustics, detection abilities, anthropogenic noise sources and the effects of such stimuli was provided (Chapter 1). Playbacks were undertaken in the field using a purpose-built underwater transducer array capable of accurately reproducing man-made signatures (Chapter 2 – 3). The behavioural responses of wild, unrestrained schooling pelagic fish to impulsive sound were observed using an acoustic observation system. Precise exposure levels were linked to specific responses, with dose response curves produced for two pelagic species of varied hearing abilities. Baited remote underwater video (BRUV) was used to observe the behavioural responses of free-ranging individual fish and crustaceans exposed to impulsive sound and shipping noise. In both cases responses varied according to the level of sound, the type of school and the species. In the laboratory, animals were exposed to sinusoidal vibratory signals using a fully calibrated electromagnetic shaker system. The sensitivity of unconditioned invertebrates (crustaceans and molluscs) to substrate-borne vibration was quantified with controlled vibratory exposures, allowing the production of a sensory threshold curve for three species (Chapters 4 - 5). Response variation was described in terms of two behavioural indicators, and related to consistency within individuals (personality), morphological parameters and time in the laboratory prior to tests. Further work investigated the response of sessile invertebrates to vibration, with the observations fully described in terms of response occurrence, duration and variation for both grouped and solitary animals. The responses described in each chapter were related to actual measurements of anthropogenic noise sources in terms of water-borne and substrate-borne energy, allowing behavioural responses to be translated to actual conditions. The data here provide evidence for the levels of playback sound to induce a behavioural response, and are fully reproducible to allow further testing of the responsiveness of fish to different sound levels and signatures. Furthermore, the data are a first step towards understanding the sensitivity of benthic invertebrates to substrate-borne vibration and indicate that the effects of substrate transmission should not be overlooked when investigating the effects of noise pollution on the marine environment. The results from the current work, along with the recommendations for future work, will be important to aid the filling of the ‘information gaps’ that exist within the underwater bioacoustics field.

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30

Kusi, Joseph. "Potential Toxicity of Silver Nanoparticles to Microbial Communities and Macroinvertebrates." Digital Commons @ East Tennessee State University, 2020. https://dc.etsu.edu/etd/3780.

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Silver nanoparticles (AgNPs) are the most common nanomaterials incorporated in commercial products due to their antimicrobial activity. Recently, AgNPs were detected in surface waters suggesting the potential for bioavailability in the aquatic receptor organisms. This dissertation research attempts to understand the potential toxicity of AgNPs on water quality indicators, focusing on the microbial community and amphipods. This study evaluated whether: (1) the antimicrobial properties of AgNPs pose potential risks to microbial communities in pathogen impaired streams; (2) AgNPs can cause a shift in functional diversity and metabolic fingerprinting of microbial communities; (3) survival and growth of Hyalella azteca (amphipods) could be affected by AgNPs; and (4) surface coating agents influence AgNP toxicity in H. azteca. Microbial community responses to AgNPs were assessed using standard plate count, microbial enzyme assays, and carbon substrate utilization with Biolog EcoPlates™. Ten-day and 28-d toxicity tests were conducted in a static system to assess AgNP effects on H. azteca. AgNPs caused a 69% decrease in microbial concentration and a 77% decrease in β-glucosidase activity at 0.32 mg Ag kg-1 dry sediment. The substrate utilization pattern of the microbial community was altered by AgNPs at 0.33 mg Ag kg-1 dry sediment. Ten-day LC50s for the survival of H. azteca were 3.3, 9.2, and 230.0 µg Ag L-1 for AgNO3, citrate-AgNP, and PVP-AgNP, respectively, whereas the 28-d LC50s were 3.0, 3.5, and 66.0 µg Ag L-1 for AgNO3, citrate-AgNP, and PVP-AgNP, respectively. The EC20s for growth (calculated as biomass) for the 10-d test were 1.6, 4.7, and 188.1 µg Ag L-1 for AgNO3, citrate-AgNP, and PVP-AgNPs; while the 28-d EC20s for AgNO3, citrate-AgNP and PVP-AgNP were 3.2, 0.5, and < 50 µg Ag L-1. The NOECS for dry weight were 4 and 1, and 100 µg Ag L-1, while those for biomass were 2, 0.5, and < 50 µg Ag L-1 for AgNO3, citrate-AgNP, and PVP-AgNP, respectively. The overall toxicity followed the trend: AgNO3 > citrate-AgNP > PVP-AgNP. The studies suggest that AgNPs pose potential risks to microbial communities and epibenthic macroinvertebrates used as bioindicators of water quality to protect public health and ecosystem health.

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31

Bessom, Stephanie Marie. "Availability and Toxicity of Nickel to Lotic Periphyton and Macroinvertebrates." Wright State University / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=wright1229483842.

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32

Carey, Nicole. "Effect of drying flow regimes on macroinvertebrates in headwater streams." Thesis, Carey, Nicole (2021) Effect of drying flow regimes on macroinvertebrates in headwater streams. PhD thesis, Murdoch University, 2021. https://researchrepository.murdoch.edu.au/id/eprint/63962/.

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In many regions, global warming is causing drying in perennial streams and prolonged drying in intermittent streams. Flow regime strongly influences stream ecosystems, so changing regimes are predicted to alter stream biodiversity and function. This thesis investigated the effect of flow regime change (perennial to intermittent) on macroinvertebrate communities in headwater streams in south western Australia (SWA), a region that has already experienced substantial climatic drying. I used a multiple before-after, control-impact design where controls comprised stream reaches that remained perennial and impact reaches were perennial until 2000s and then became intermittent. Before-drying information came from Bunn’s 1985 PhD thesis and I collected after-drying data from the same reaches in 2016-2017. Many species (including SWA endemics) were lost from streams that became intermittent, which also supported drying-adapted species, including new arrivals. Regardless of flow regime, high species turnover characterised both spatial and temporal beta-diversity in assemblages. Species traits did not adequately predict persistence under intermittency. Of the 13 formerly most-common species, seven were restricted to perennially flowing streams, and only four (two mayflies, one stonefly, one amphipod) adapted their life histories to intermittency. Bunn (1985) showed that leaf-litter breakdown was moderated by macroinvertebrates in these streams. By repeating his experiment, I showed that leaf-litter breakdown processes had remained similar in intermittent and perennial streams, despite the loss of most large macroinvertebrate shredders. To survive drying, invertebrates used a similar range of drought refuges identified in other studies. Altogether, these results demonstrate profound alterations to macroinvertebrate communities in streams forced into intermittency, particularly the loss of relictual and functionally important species. Given that current understanding of traits did not predict species persistence, life history research should focus on understanding trait flexibility. Identification and protection of evolutionary refugia is urgent in regions undergoing climatic drying because substantial biodiversity loss is imminent there.

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33

Eisele, Shante N. "Comparing created and natural depressional wetlands through trophic analysis of macroinvertebrates." Wright State University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=wright1547577007255219.

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34

Tornero, Pinilla Irene. "Metacommunities and biodiversity patterns in Mediterranean temporary ponds: the role of pond size, network connectivity and dispersal mode." Doctoral thesis, Universitat de Girona, 2020. http://hdl.handle.net/10803/670096.

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We sampled the macrofaunal metacommunities in four networks of Mediterranean temporary ponds covering a wide range of pond sizes and different spatial extents. 1) In the smallest pond network, pond size was not related to any of the environmental factors and neither to community structure but had an effect on community composition. The effect of a high connectivity could explain the absence of differences in community structure. 2) Environmental distance had larger effects than spatial distance in the decay of community similarities. In the smaller network, the biotic groups showed different distance-decay patterns. In the larger network all the groups fit in the species sorting archetype. 3) We observed that centrality metrics affect regional and local pond biodiversity. Biodiversity metrics were not explained by environmental characteristics or centrality metrics alone, but through a combination of them. Regional biodiversity metrics showed similar patterns in all the networks, whereas local ones showed greater network-dependent patterns
Se muestrearon las comunidades de macrofauna en cuatro redes de lagunas temporales mediterráneas que presentan un rango amplio de tamaños de lagunas y distintas extensiones espaciales. 1) En la red de lagunas más pequeña, el tamaño de la laguna no estaba relacionado con ninguno de los factores ambientales ni con la estructura de la comunidad pero sí tuvo efecto en la composición de la comunidad. El efecto de una alta conectividad podría explicar la ausencia de diferencias en la estructura de la comunidad. 2) La distancia ambiental produjo mayores efectos que la distancia espacial en la pérdida de similitud de las comunidades. En la red más pequeña, los grupos bióticos mostraron diferentes patrones de pérdida de similitud con la distancia. En la red más grande todos los grupos parecen encajar en el arquetipo de ‘filtro de las especies’. 3) Observamos que las métricas de centralidad afectaban a la biodiversidad regional y local. Las métricas de biodiversidad no se explicaban solo por las características ambientales o las métricas de centralidad sino por una combinación de ambas. Las métricas de biodiversidad regional mostraron patrones similares en todas las redes mientras que las locales mostraron patrones dependientes de la red

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35

McNish, Julie Helen. "An interdisciplinary assessment of variations in acidity in Yorkshire rivers, with special reference to episodic acidification of headwaters in the Esk catchment." Thesis, University of Huddersfield, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.285628.

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36

Costa, Talitha Rochanne Alves Abreu da. "AvaliaÃÃo da qualidade de Ãgua do reservatÃrio GaviÃo utilizando macroinvertebrados como bioindicadores." Universidade Federal do CearÃ, 2013. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=11312.

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nÃo hÃ
A preocupaÃÃo com processos que causam degradaÃÃo da qualidade dos recursos hÃdricos e dos ecossistemas aquÃticos tem se acentuado, principalmente, devido a enorme quantidade de poluentes e novas substÃncias que adentram nesse meio. Objetivou-se, com este trabalho, ampliar o conhecimento sobre a comunidade de macroinvertebrados aquÃticos do reservatÃrio GaviÃo em Itaitinga (CE), onde ocorre a captaÃÃo das Ãguas para o sistema de abastecimento de Ãgua da regiÃo metropolitana de Fortaleza e avaliar como os organismos respondem Ã disposiÃÃo dos resÃduos da ETA GaviÃo, utilizando o Ãndice BMWPâ. As coletas foram realizadas mensalmente, empregando um coletor do tipo Surber (500 Âm de abertura de malha) no perÃodo de outubro 2012 a maio de 2013. Foi coletado um total de 1.621 espÃcimes, distribuÃdos em 23 taxa. Mollusca foi o grupo dominante e frequente e Insecta apresentou maior riqueza. Segundo o Ãndice BMWPâ, verificou-se que o reservatÃrio GaviÃo encontra-se com suas Ãguas em qualidade duvidosa.
Concerns with the processes that cause water resources and ecosystem degradation are on the rise, especially because of large amounts of pollutants and substances that enter this medium. This study aimed to evaluate water macroinvertebrate communities in tanks used for water collection for urban use and to assess how organisms respond to waste generated in the water treatment plant. We collected a total of 1,621 specimens, distributed into 23 taxa. Mollusca was the dominant and frequent group and insecta was the most abundant. Based on feeding mode, there are more predatory organisms in relation to scrapers. We found no eudominant families. By using the BMWPâ score we verified that water quality in the âGaviÃoâ reservoir is questionable.

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Barbosa, Domingos Sávio. "Limnologia do rio Uberaba (MG) e a utilização de macroinvertebrados bentônicos como bioindicadores das modificações ambientais." Universidade de São Paulo, 2003. http://www.teses.usp.br/teses/disponiveis/18/18139/tde-29042009-143849/.

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Os sistemas lóticos são considerados sistemas abertos e de fluxo unidirecional de energia. Nestes sistemas a intensa relação com o meio terrestre adjacente faz com que as condições ecológicas dos rios sejam um reflexo das transformações ocorridas em sua bacia de drenagem. O objetivo do presente estudo foi traçar um perfil dos aspectos ecológicos do rio Uberaba-MG, em função dos usos preponderantes da bacia hidrográfica. Foram avaliadas as características limnológicas, a comunidade de macroinvertebrados bentônicos e o estado de conservação da área de entorno do rio. Procurou-se ainda avaliar a evolução espacial e a variação temporal das variáveis mensuradas à luz de teorias ecológicas de sistemas lóticos. Os resultados mostraram que no rio Uberaba três zonas com impactos preponderantes, diferentes, devem ser avaliadas com maior cautela: a) antes do município de Uberaba existe a predominância de atividades agrícolas, que promovem impactos pela entrada contínua de sedimentos e oferecem riscos pela entrada de agrotóxicos e fertilizantes, b) abaixo do município de Uberaba, a entrada de efluentes gera acentuada degradação da qualidade da água e o conseqüente perecimento das comunidades biológicas, até a região próxima ao município de Veríssimo, e c) a região compreendida entre os municípios de Veríssimo, Conceição das Alagoas e Planura, pelo crescente risco de degradação da qualidade da água decorrente da entrada de efluentes e do aumento do desmatamento nas margens do rio Uberaba e afluentes. Discute-se ainda a necessidade de serem aprimoradas teorias ecológicas para sistemas lóticos tropicais, com o intuito de aumentar a capacidade de predição sobre este sistema e remeter estratégias de conservação mais eficientes aos gestores ambientais.
Lotic systems are considered opened and one-way energy flux systems. In these cases, the intense relationship with adjacent terrestrial environment renders rivers ecological conditions a reflex of transformations occurred at its watershed. The present study aimed to profile an Uberaba river ecological features as a function of the watershed main uses. Limnological characteristic, benthic macroinvertebrates community and conditions at river nearby area were evaluated. Based on the lotic systems ecological theories, it was attempted to evaluate the measured variable space evolution and temporal variation. Results showed that in Uberaba river, three zones with different impacts should be carefully evaluated: a) before Uberaba city, agricultural activities predominates, promoting impacts due to the continuous sediment input, and offering risks of pesticide and fertilizers contribuition; b) below Uberaba city, wastewater effluent generates high water quality degradation, resulting in biological communities decay until the area closed to Veríssimo City; and c) at the region embracing Veríssimo, Conceição das Alagoas and Planura cities, in function of the growing water quality degradation risk due to effluents entrance and deforesting increase at the margins of Uberaba river and tributaries. The needs of improved ecological theories for tropical lotic systems are also discussed, aiming to increase the prediction capacity on this lotic systems and to transmit more efficient conservation strategies to environmental managers.

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38

Beliene, Glieber Henriques. "Efeitos de bivalves, gastrópodes e fatores ambientais sobre a abundância de macroinvertebrados em lagoas adjacentes ao Rio Cuiabá-MT." Universidade Federal de Mato Grosso, 2015. http://ri.ufmt.br/handle/1/239.

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CAPES
FAPEMAT
CNPq
Interações entre organismos de uma comunidade podem determinar a distribuição e abundância das espécies. Os resultados dessas interações podem ser positivos ou negativos. Além das interações, existem diversos fatores ambientais influenciando essas relações. Em ambientes aquáticos, moluscos induzem transformações na comunidade macrobentônica, alterando a distribuição e abundância desses organismos. Devido a isso investiguei os efeitos de Bivalves, do gastrópode exótico Melanoides tuberculatus e de variáveis ambientais sobre as abundâncias da comunidade de macroinvertebrados bentônicos em lagoas próximas ao rio Cuiabá. As abundâncias de macroinvertebrados parecem sofrer efeitos de variáveis ambientais. Elas também variaram em função da presença e ausência de Bivalves e M. tuberculatus. Observei que Ceratopogonidae, Hirudinea e Ostracoda responderam negativamente as variáveis (Dureza e Turbidez); Chironomidae, Ceratopogonidae, Oligochaeta responderam negativamente a presença de M. tuberculatus; Zygoptera, Ostracoda e Oligochaeta responderam positivamente a presença de bivalves. Outras variáveis que aqui não foram mensuradas podem exercer influência sobre as interações aqui abordadas, sendo esse um tema para futuros trabalhos.
Interactions between organisms of one community can determine the distribution and abundance of species. The results of these interactions can be positive or negative. In addition to the interactions, there are several environmental factors influencing these relationships. In aquatic environments, molluscs induce changes in the macrobenthic community, changing the distribution and abundance of these organisms. Because of this, investigated the effects of bivalves, exotic gastropod Melanoides tuberculatus and environmental variables on the abundance of the benthic macroinvertebrate community in lakes near the river Cuiabá. The abundance of macroinvertebrates seem to be affected by environmental variables. it also varied according to presence and absence of Bivalve and M. tuberculatus. Noticed that Ceratopogonidae, Hirudinea and Ostracoda negatively answered variables (Hardness and Turbidity); Chironomidae, Ceratopogonidae, Oligochaeta negatively answered the presence of M. tuberculatus; Zygoptera, Ostracoda and Oligochaeta responded positively to the presence of Bivalve. Other variables that were not measured here can influence the interactions discussed here, making a topic for future work.

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Vasconcelos, Márlon de Castro. "Classificação de rios e sua relação com a comunidade de macroinvertebrados em riachos." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2012. http://hdl.handle.net/10183/72393.

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Nesta tese avaliei a relação entre a classificação de riachos em tipos de rios baseados nas suas características abióticas com a comunidade de macroinvertebrados. Especificamente, avaliei as seguintes questões: 1) Como as escalas de trecho de rio (local) e de bacia hidrográfica (regional) influenciam as comunidades? 2) As classificações de rios baseadas em variáveis abióticas são concordantes com aquelas baseadas em macroinvertebrados? 3) As respostas das comunidades de macroinvertebrados são similares quando diferentes abordagens de classificação são usadas? Por fim, 4) De que forma a resolução taxonômica e o tratamento dos dados influenciam as perguntas 2 e 3? Este estudo foi realizado em 38 riachos, numa área de 282 mil km2 no Rio Grande do Sul. As distâncias entre os riachos variaram entre 15 a 670 km. As variáveis físicas e químicas dos rios foram obtidas em trechos de 50 metros de extensão. A bacia hidrográfica de cada trecho foi delimitada e o uso da terra, tipo de solo e o relevo foram obtidos por meio de SIG. A tese traz uma “Apresentação geral” como Introdução. O capítulo 1 cobre a revisão da literatura e foi publicado na revista Ciência e Ambiente. O capítulo 2 apresenta a relação das variáveis ambientais e do espaço (distância geográfica) com a comunidade de macroinvertebrados. Como principal resultado, observou-se que o ambiente explica a maior parte da variação da distribuição na comunidade de macroinvertebrados, sendo que o efeito do ambiente é dependente da resolução taxonômica utilizada. No capítulo 3 avaliei a concordância entre classificações bióticas e abióticas. Avaliamos concomitantemente o efeito da resolução taxonômica, tipo de dado e da escala (trecho de rio x bacia hidrográfica). Tanto o tipo de dado quanto a resolução taxonômica influenciaram os resultados, sendo a classificação baseada nos dados no nível de família o único concordante com a classificação baseada em dados abióticos (duas escalas juntas). Outro importante resultado obtido foi a observação de que em uso de diferentes escalas, separadamente, verifica-se que a concordância se deu apenas para a escala de bacia hidrográfica, desde que para abundância no nível de gênero e presença/ausência no nível de família. No capítulo 4 verifiquei a relação da comunidade de macroinvertebrados com cinco sistemas de classificações de rios. As duas primeiras são baseadas em hidrorregiões, a terceira, em ecorregiões aquáticas da FEOW, a quarta deriva das ordens dos rios e a quinta é resultado do agrupamento de variáveis ambientais medidas localmente e regionalmente. Os resultados demonstram que a classificação baseada em variáveis ambientais se apresentou como o melhor sistema de classificação dos rios amostrados. Também avaliamos o tipo de dado e resolução taxonômica. Novamente a resolução taxonômica foi importante para os resultados obtidos e os dados de gênero obtiveram os melhores resultados. Por fim, na última parte da tese são apresentadas as considerações finais.
This thesis evaluated the relationships between stream classifications according to their abiotic characteristics and macroinvertebrate stream assemblages. Specifically, I asked the following questions: 1) How the macroinvertebrate communities are related with stream reach and catchment scales ? 2) Are the streams classifications with biotic and abiotic approach congruent? 3) Are there similar responses of macroinvertebrate assemblages when different classification approaches are used? 4) Can the taxonomic resolution and data type (abundance and presence/absence) to influence the results? This study was conducted in 38 streams, with distances among streams ranged from 15 to 670 km at an area of 282.000 km2 in Rio Grande do Sul state. The chemical and physical variables were obtained at a 50 m reach in each stream. The catchment was delimited and land use, soil coverage and relief were obtained using GIS tools. The thesis includes an “overview” as introduction. Chapter 1 covers the literature review and was published on Ciência e Ambiente. The Chapter 2 shows the relationship of environmental variables and space (distance among streams) with macroinvertebrate assemblages. The main result was that the environment accounted for most of the variation on the distribution of macroinvertebrate assemblages and this effect was dependent of the taxonomic resolution. In chapter 3 I evaluated the concordance between the abiotic and biotic classifications as well as the effect of the numerical and taxonomic resolution and the scale (stream reach x catchment). The results are dependent of the taxonomic resolution and dada type. The most important result was the effect of taxonomic resolution on the concordance between biotic and abiotic classifications. The classification based on macroinvertebrate family data was the only biotic classification concordant with the classification based on abiotic data. Another important result is that different scales, when used separately, only catchment classification was concordant with biotic one, and this result was dependent of both taxonomic and dada type. In chapter 4 we assessed the relationship of macroinvertebrate assemblages with five stream classifications. The first two is based on catchments grouped in hydrologic units, the third is based in freshwater ecoregions of FEOW, the fourth is based on stream orders and the fifth is result by cluster of environmental variables get on stream reach and catchment scales. That classification based on environmental variables had the higher scores than others classification by Classification Strength approach. The taxonomic and numeric resolutions were also evaluated. The taxonomic resolution was important to the results obtained, and genera data show the best scores. In the last part of the thesis are presented the conclusion remarks.

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Khan, Muhammad Irfan. "A lotic microcosm for ecological and ecotoxicological studies on benthic macroinvertebrates." Thesis, Imperial College London, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.320214.

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Neale, Martin William. "Classifying and measuring the ecological status of lakes using benthic macroinvertebrates." Thesis, University of Ulster, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.414101.

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Stockley, Rosalind Antonia. "Detritus processing in the River Swale-Ouse : the role of macroinvertebrates." Thesis, University of York, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.298585.

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Tharme, Rebecca Elizabeth. "Ecologically relevant low flows for riverine benthic macroinvertebrates: characterization and application." Doctoral thesis, University of Cape Town, 2010. http://hdl.handle.net/11427/11040.

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Intensifying hydrologic alteration and the resultant degradation of river ecosystems worldwide have catalyzed a growing body of ecohydrological research into the relationships between flow regime attributes, physical habitat dynamics and biotic response, particularly for determining environmental flows. While invertebrate response to floods has received most attention, in this thesis the aim was to identify and characterize low flows that constituted various degrees of physical disturbance to benthic macroinvertebrate assemblages of perennial rivers.

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McTammany, Matthew Eric Jr. "The Impact of Urbanization on Benthic Macroinvertebrates in Southern Appalachian Streams." Thesis, Virginia Tech, 1998. http://hdl.handle.net/10919/46508.

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Macroinvertebrate assemblage structure was compared from 12 streams differing in urbanization type and degree. Urbanization, both historical and current, was measured using several variables generated from GIS overlays of land cover, aerial photographs, and field exploration in the study watersheds. Quantitative benthic macroinvertebrate samples were taken, and a variety of physicochemical characteristics were measured. Increasing urbanization resulted in a decline in diversity and abundance of intolerant organisms. Streams in industrial areas had greater invertebrate density due to large increases in a few tolerant groups. Urbanization in the watersheds was coupled with changes in the physical and chemical structure of the streams suggesting some possible mechanisms for urbanization impact on stream biota. Multivariate analysis grouped streams based on a number of pollution-sensitive taxa suggesting the utility of this type of approach in analyzing community data. Primary funding for this project was from the Coweeta Hydrologic Lab NSF-LTER grant. Additional funding was provided through a Graduate Research and Development Project grant from the Graduate Student Assembly of Virginia Polytechnic Institute and State University. Matching funds were provided by the Biology Department.
Master of Science

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Kaller, Michael D. "Effects of sediment upon benthic macroinvertebrates in forested northern Appalachian streams." Morgantown, W. Va. : [West Virginia University Libraries], 2001. http://etd.wvu.edu/templates/showETD.cfm?recnum=1862.

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Thesis (M.S.)--West Virginia University, 2001.
Title from document title page. Document formatted into pages; contains x, 157 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references.

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Leite, Ricardo Cardoso. "Biodiversidade em microescala: uma perspectiva para a ecologia de sistemas lóticos." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/59/59131/tde-02072014-113205/.

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Este trabalho enfatizou as escalas espaciais de microhabitat e de mesohabitat para investigar como a fauna de macroinvertebrados aquáticos é influenciada pelas variáveis ambientais e espaciais. O primeiro capítulo trás uma visão geral da aplicabilidade das escalas de microhabitat e de mesohabitat ao avaliar a estrutura da fauna e, também, demonstra que a composição do substrato influencia a composição faunística. No segundo capítulo, realizamos uma avaliação da suficiência amostral e comparamos a diversidade alfa e beta entre métodos de coleta e entre diferentes mesohabitats. No terceiro capítulo avaliamos diferentes variáveis hidráulicas e suas relações com a abundância de indivíduos e a riqueza de táxons considerando as escalas espaciais de microhabitat e mesohabitat. Observamos que as condições hidráulicas foram importantes na estruturação da comunidade de macroinvertebrados, influenciando positivamente a abundância de indivíduos e negativamente a riqueza de táxons nos microhabitats. No quarto capítulo nos baseamos na teoria de metacomunidades para compreender a influência das variáveis ambientais e espaciais na estruturação da fauna em uma perspectiva de microescala. Além da esperada importância do ambiente para a microdistribuição dos organismos, identificamos uma forte influência do espaço na estruturação da fauna. Nossos resultados demonstraram que a fauna de macroinvertebrados aquáticos é estruturada pela composição do substrato, condições hidráulicas e fatores espaciais, todas estas condições perceptíveis na escala do microhabitat. Deste modo, a microescala pode ser considerada como uma perspectiva válida para o estudo de ecologia de riachos.
We focused on the microhabitat and the mesohabitat spatial scales to investigate the environmental and spatial features influence on aquatic macroinvertebrate fauna. The first chapter brings an overview about the microhabitat and mesohabitat applicability to evaluate the fauna structure. Likewise, it shows the substrate influence on the fauna composition. In the second chapter, we evaluate the sampling sufficiency and compare the alpha and beta diversity among the sampling methods and mesohabitats. In the third chapter we evaluated the hydraulic features and its relationships with abundance and richness considering the microhabitat and mesohabitat spatial scales. Our results show that the hydraulic conditions have influence on macroinvertebrate community structure, showing a positive relationship with abundance and negative with microhabitat richness. In the fourth chapter, we applied the metacommunity theory in the microhabitat scale to understand the hole of environmental and spatial features on the community structure. Further than the expected environmental influence on organisms microdistribution, we identified a strong spatial influence on the fauna structure. Our results showed that the aquatic macroinvertebrate fauna was structured by the substrate composition, hydraulic conditions and spatial features. All this conditions are noticeable on microhabitat spatial scale. Accordingly, the microhabitat scale can be considered as an effectual perspective to the stream ecology.

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Malacarne, Tássia Juliane. "Efeitos do uso do solo na estrutura e composição de invertebrados aquáticos e no processo de decomposição foliar em riachos neotropicais." Universidade Estadual do Oeste do Parana, 2015. http://tede.unioeste.br:8080/tede/handle/tede/707.

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Made available in DSpace on 2017-07-10T14:38:28Z (GMT). No. of bitstreams: 1 tassia.pdf: 1244152 bytes, checksum: 94c85e90bbbe81a039be502cd6b74f66 (MD5) Previous issue date: 2015-02-26
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Different land uses directly affect the characteristics of a river basin, reflecting the health and integrity of the aquatic environment, and consequently influence the aquatic biota and ecosystem processes. This study aimed to analyze the structure and community composition of aquatic invertebrates and the role of these organisms in the process of decomposition of leaf litter in streams with different land uses. Samples were collected in the period from September to December 2013 in five streams of western Paraná. At each stream were placed 18 bags containing litter for colonization by aquatic invertebrates during the exposure times of 15, 30, 45, 60, 75 and 90 days. Significant spatial differences in the structure and composition of the community of aquatic invertebrates in the studied streams were recorded. There were no significant differences in the activity of aquatic invertebrates in the leaf decomposition process streams with different land uses. But there were differences in the variability of decomposition between the streams, and the reference stream showed lower variability in the decomposition process. This result may have been influenced by habitat quality, availability of organic matter, and the structure and composition of benthic community present in the reference stream, which differs significantly between locations with different types of land use. The results of this study demonstrate that human interference in the aquatic environment through land use can influence negativity in ecosystem processes, particularly in invertebrate activity during the processing of allochthonous material, as well as modify the structure and composition of the biota.
Diferentes usos do solo afetam diretamente as características de uma bacia hidrográfica, refletindo na saúde e integridade do ambiente aquático, e, consequentemente, influenciam a biota aquática e os processos ecossistêmicos. Este trabalho teve como objetivo analisar a estrutura e composição da comunidade de invertebrados aquáticos e o papel desses organismos no processo de decomposição de detritos foliares em riachos com diferentes usos do solo. As coletas foram realizadas no período de setembro a dezembro de 2013 em cinco riachos da região oeste do Paraná. Em cada riacho foram colocadas 18 bolsas contendo folhiço para a colonização por invertebrados aquáticos durante os tempos de exposição de 15, 30, 45, 60, 75 e 90 dias. Foram registradas diferenças espaciais significativas na estrutura e composição da comunidade de invertebrados aquáticos entre os riachos estudados. Não houve diferenças significativas na atividade de invertebrados aquáticos durante o processo de decomposição foliar em riachos com diferentes usos do solo. Porém houve diferenças na variabilidade da decomposição entre os riachos, sendo que o riacho de referência apresentou menor variabilidade no processo de decomposição. Esse resultado pode ter sido influenciado pela qualidade do hábitat, disponibilidade de matéria orgânica, e pela estrutura e composição da comunidade bentônica presente no riacho de referência, a qual difere significativamente entre os locais com diferentes tipos de ocupação do solo. Os resultados deste estudo demonstram que a interferência humana no ambiente aquático, por meio do uso do solo, pode influenciar negatividade nos processos ecossistêmicos, em especial na atividade de invertebrados durante o processamento de material alóctone, além de modificar a estrutura e composição da biota.

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Nin, Cecília Schüler. "Quebra foliar e colonização de macroinvertebrados em riachos do bioma pampa." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2010. http://hdl.handle.net/10183/78155.

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Dois estudos envolvendo processos ecológicos de decomposição foliar e colonização por macroinvertebrados foram realizados em três nascentes do bioma Pampa. O primeiro deles questionou se as folhas podem ter processos diferenciados quando estão misturadas, ou seja, se há efeito aditivo de uma folha sobre as outras e se a fauna decompositora seleciona recursos na forma desse composto heterogêneo. Para tanto, quatro espécies mais comuns da mata de galeria desses riachos foram coletadas e incubadas em bolsas-de-folhiço. A taxa de decomposição das folhas quando misturadas não é diferente da média de todas as espécies isoladas, indicando que não existe efeito de uma espécie sobre as outras. A colonização de macroinvertebrados não respondeu a diferenças dos detritos, tanto para abundância quanto para composição da fauna, indicando que as morfoespécies não têm preferência por tipos de folhas. Em relação aos grupos tróficos funcionais, não existe seleção entre os diferentes detritos - mesmo quando misturados - mas sim um forte padrão de sucessão no tempo. Herbívoros e omnívoros possuem maior freqüência nas primeiras etapas do processo, seguidos de detritívoros e carnívoros mais nas etapas finais. Já o segundo estudo se propõe a investigar se a presença de folhas de Eucalyptus saligna (exótica) junto às de nativas tem efeito na taxa de decomposição total da mistura em resposta as suas diferentes pressões de seleção, como por exemplo, seus metabólitos secundários. A taxa de decomposição tanto de E. saligna, quanto dessas folhas misturadas às nativas, é considerada lenta, sendo que folhas de E. saligna isoladas foi a mais rápida, ficando no limite ente lenta a intermediária. A taxa de decomposição do tratamento nativas + E. saligna foi diferente daquela esperada pela média de todas as espécies isoladas (nativas + exótica). A densidade de macroinvertebrados foi diferente entre folhas de E. saligna e desta misturada às nativas, sendo a maior riqueza de morfoespécies associada às folhas da espécie exótica. Não há padrões quanto à estrutura da assembléia de macroinvertebrados associados às diferentes folhas, e nem entre os tempos. A mesma falta de agrupamento ocorre para os grupos funcionais. E. saligna obteve uma taxa de decomposição mais acelerada provavelmente por apresentar baixo teor de lignina e, ainda, pela rapidez com que geralmente os polifenóis são lixiviados. O esperado para a decomposição do tratamento nativas + E. saligna foi uma taxa maior daquela observada, possivelmente porque as folhas nativas apresentam uma estrutura tecidual mais íntegra, providenciando uma desaceleração da taxa de decomposição das folhas de eucalipto na mistura. Portanto, tanto o processo de decomposição quanto a colonização de macroinvertebrados do tratamento de nativas sob influência da exótica se deu mais em função das espécies nativas ali presentes.
Two studies involving ecological processes of leaf decomposition and macroinvertebrate colonization were performed on three headwater streams of the Pampa biome. The first verified if the leaves may have different decomposition process when they are mixed, in other words, if there is additive effect of a film on the other, and if the fauna selects resources in the form of this heterogeneous compound. To achieve that, the four most common species of the gallery forest of these streams were collected and placed in litter-bags. The leaf breakdown rate when mixed is not different from the average of all species isolated, indicating that there is no effect of one species over the others. The colonization of macroinvertebrates did not respond to differences of detritus, both to the abundance and for fauna composition, indicating that the morphospecies have no preference for the leaves kind. Regarding the functional feed groups, there is no selection among the different debris - even when mixed - but a strong pattern of temporal succession. Herbivores and omnivores have higher frequency in the early stages of the decomposition followed by detritivores and carnivores in the final stages. The second study aims to investigate whether the presence of Eucalyptus saligna (exotic) plus native leaves affect the decomposition rate of the mixture since these leaves have experienced different selection pressures and therefore have different mechanisms of decomposition, for example, have developed different secondary metabolites. The decomposition rate of both E. saligna, and these leaves mixed with native, were considered slow, but the E. saligna leaves alone had the fastest decomposition rate, being in the limit between slow and intermediate. The leaf breakdown rate of native + E. saligna was different from that expected by the average of the isolated species (native + exotic). The density of macroinvertebrates was different between of E. saligna and native plus eucalypt leaves, with the greatest richness of morphospecies associated with the leaves of the exotic one. There were no standards in the assembly of macroinvertebrates associated with the different leaves, or between times. The same lack of clustering occurs for the functional feed groups. E. saligna obtained a faster decay rate probably because of its low lignin content, and also the speed with which the polyphenols are generally leached. The expected for the decomposition rate of native + E. saligna was higher than the observed, possibly because the leaves have a native tissue structure more fully, providing a deceleration in the decomposition rate of eucalyptus leaves in the mix. Therefore, both the process of decomposition and colonization by macroinvertebrates under the influence of the exotic, were more associated with the presence of the native species.

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Ruhí, i. Vidal Albert. "Primary succession in man-made wetlands: biodiversity, structure and dynamics of macrofaunal assemblages." Doctoral thesis, Universitat de Girona, 2012. http://hdl.handle.net/10803/77638.

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Man-made wetlands are often created to compensate for the loss or degradation of natural wetlands, but little is known about the processes taking place in these artificial environments, especially at the community level. Throughout this thesis, we have assessed the phenomena of primary succession over different time (short-, mid- and long-term) and spatial scales (local, regional, interregional levels), applying different approaches (taxonomic and functional) and subject groups (invertebrates and amphibians). Our main findings regarding time scales show a 3-phase successional pattern in Mediterranean man-made wetlands’ communities, where at the short term (1 year) colonization processes dominate; at mid term perspectives (2 to 7 years) succession signs begin to be conspicuous, and later on (≥ 10 years) parameters such as species richness reach an asymptote. At that moment, some biological strategies dominate, and biodiversity surrogates indicate that communities are indistinct between man-made and natural wetlands. Regarding spatial effects, we corroborated that both local and regional factors affect the establishing communities. Particularly, the low hydrological stability of the Mediterranean region has enhanced biological traits favoring resilience and resistance to disturbances when comparing Mediterranean and cold temperate aquatic communities. Even within the Mediterranean region, low levels of hydrological stability have significant effects on the successional dynamics. In these cases, local communities are highly nested within regional natural ones, and so are not able to make net contributions to regional richness. We also showed the influence of the regional pool of recruiters over local communities, both in the case of invertebrates and amphibians. Especially for the latter group, man-made Mediterranean temporary ponds (MTPs) can play an important role in their conservation.
Les zones humides de nova creació són sovint concebudes per compensar la pèrdua i degradació de les naturals, però el coneixement dels processos que tenen lloc en aquests ambients artificials encara és superficial, especialment a nivell de comunitat. Al llarg d’aquesta tesi, hem analitzat el fenomen de la successió primària a diferents escales temporals (a curt, mitjà i llarg termini) i a diferents escales espacials (a nivell local, regional i interregional), mitjançant diverses aproximacions (taxonòmiques i funcionals) i subjectes (invertebrats i amfibis). Les nostres aportacions pel que fa a les escales temporals mostren un patró de successió basat en 3 fases, on a curt termini (1 any) dominen els processos de colonització; en perspectives de mitjà termini (2 a 7 anys) els signes de successió comencen a ser conspicus, i més tard (≥ 10 anys) paràmetres com la riquesa d’espècies arriben a una asímptota. En aquesta fase avançada, algunes estratègies biològiques dominen, i els índexs de biodiversitat indiquen que les comunitats poden ser indistintes entre les llacunes naturals i les de nova creació. Pel que fa als efectes espacials, hem corroborat que tant factors locals com regionals afecten les comunitats que s’hi estableixen. En particular, la baixa estabilitat hidrològica de la regió Mediterrània ha afavorit trets biològics que proveeixen resiliència i resistència enfront de pertorbacions, sobretot quan es comparen amb les comunitats pròpies del clima temperat fred. Fins i tot dins la mateixa regió Mediterrània, nivells baixos d’estabilitat hidrològica poden tenir efectes importants en la dinàmica de la successió. En aquests casos, les comunitats locals estan altament aniuades en les naturals a nivell regional, i per tant difícilment poden fer contribucions netes a la riquesa regional. També hem mostrat la influència del pool regional de colonitzadors sobre les comunitats locals, tant en el cas dels invertebrats com en el dels amfibis. Especialment per aquest darrer grup, les Basses Temporànies Mediterrànies (BTMs) de nova creació poden jugar un paper important per a la seva conservació.

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Sandin, Leonard. "Spatial and temporal variability of stream benthic macroinvertebrates : implications for environmental assessment /." Uppsala : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 2000. http://epsilon.slu.se/avh/2000/91-576-6056-5.pdf.

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Dissertations / Theses on the topic 'Macroinvertebrates'

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