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1
Holland, Robert Alan. "Temporal variability of lotic macroinvertebrate communities." Thesis, University of Sheffield, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.713528.
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Sabine, Mary E. J. "Macroinvertebrate communities of different-aged beaver ponds." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ38407.pdf.
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Wilson, Sarah Jane. "Freshwater macroinvertebrate communities on exotic and native plants." Thesis, McGill University, 2007. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=101665.
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Aquatic plants play an important role in the survival and proliferation of invertebrates in freshwater ecosystems. Exotic plants are now common in North American lakes and rivers, where they may displace native plants, thereby potentially altering epiphytic invertebrate communities. Differences in aquatic invertebrate communities on native and exotic plants are examined here through (1) a meta-analysis of published data, and (2) two field surveys in northeastern North America that compared invertebrates on the exotic Myriophyllum spicatum and Potamogeton crispus to those on their native congeners. The meta-analysis revealed that exotic plants generally support lower invertebrate abundance than do natives, while invertebrate taxa richness tends to be similar on exotic and native plants. The field surveys demonstrated that M. spicatum and P. crispus support significantly different invertebrate densities and lower taxa richness than their structurally similar native congeners. These results suggest that the replacement of native plants by exotics---even those with similar morphology---may cause concomitant changes to aquatic ecosystems.
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Aspray, Katie Louise. "Macroinvertebrate communities and ecosystem functioning in peatland streams." Thesis, University of Leeds, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.590494.
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Headwater streams are important habitats, unique in their heterogeneity and biodiversity. they are considered significant for the functioning of whole river systems. Many headwater systems. such as those in the temperate and sub arctic northern hemisphere, drain peat dominated catchments, a habitat that is increasingly threatened by climate change, acidification and pressures from an array of land management practices. Together these impacts are resulting in the widespread degradation of peatlands and it is hypothesised that stressors could severely impact streams draining these systems, causing shifts in macro invertebrate community composition and alterations to functional process rates. However, there is a lack of information on the exact impacts of these stressors to peatland streams and, furthermore, limited knowledge of these ecosystems in their intact state. Thus, the overarching aim of this work is to improve understanding surrounding the impacts of stressors to peatland streams and to contextualise this research with an improved knowledge of the dynamics of intact peatland streams. This work focused on streams originating from blanket peats in the UK, which form important headwaters of many major UK rivers, and had four main objectives. 1) Develop a holistic understanding of an intact peatland stream through intensive assessment of physico chemistry, macroinvertebrate communities and three functional processes (algae accrual, plant litter decomposition and whole stream metabolism) using both a longitudinal survey and intense seasonal monitoring. 2) Assess the impacts of two catchment-scale drivers of change in peatland habitats (rotational heather burning and erosion) on stream ecosystems, examining physicochemistry, macroinvertebrates and ecosystem functioning across fifteen streams. 3) Examine gradients of sedimentation associated with environmental change and land management using streamside mesocosm and reach experiments. 4) Consider the mechanisms that elicit a change in physicochemisty, macroinvertebrates and ecosystem function by considering interrelationships and advancement of conceptual models. The interdisciplinary approach used in this thesis allowed a novel assessment of the spatiotemporal variability of peatland stream ecosystems and for the first time hig~lighted alterations in both macroinvertebrate communities and ecosystem functioning along the stream length and across seasons in an intact peatland stream. Increases in macroinvertebrate abundance, primary production and community vi j b respiration were observed with increasing distance downstream and with increasing catchment size. These parameters, along with algae accrual and leaf litter decomposition rates, also showed strong seasonal patterns, decreasing in winter and amplifying in summer. Variations in these parameters were driven predominantly by increases in temperature, photosynthetically active radiation (PAR), suspended sediment concentrations (SSC), discharge and dissolved organic carbon (DOC). Erosion, and to some degree rotational heather burning, were found to impact physicochemical variables, with total oxidised nitrogen (TON) and SSC displaying increased concentration.s in impacted catchments. Associated shifts were found in macroinvertebrate communities, with amplified abundance in eroded catchments driven by increases in ' more sediment tolerate taxa, such as Chironomidae and Oligo chaeta. Streams draining eroded and burnt catchments also displayed lower numbers of sensitive Ephemeroptera, Plecoptera and Trichoptera taxa. Functional parameters did not reflect these changes in chemistry and biota, but there were clear differences between the fifteen individual streams. Experiments undertaken in streamside mesocosms and stream reaches showed impacts of organic sedimentation across several levels of ecological organisation. Increased benthic sedimentation led to declines in macroinvertebrate abundance, shifts in - species composition and increased sediment respiration rates. Short term influx of organic sediment in reach based experiments caused significant increases in the downstream drift of macroinvertebrates during nocturnal periods, however, these streams were quick to recover to pre-experiment drift rates and benthic communities were not affected over the period of the experiment. These influx events produced a rapid and severe decline in GPP measured though whole stream metabolism rates, This body of research highlights peatland streams as unique and heterogenic systems but also as systems that are sensitive to anthropogenic stressors at both the catchment and reach scale, These habitats have intrinsic importance, supporting diverse macroinvertebrate communities, are significant for the modulation of carbon and are good indicators of the condition of the surrounding catchment. Thus, this work emphasises the need for restorative measures and sustainable management in peatland habitats that considers the streams they support. In addition, this work furthers knowledge of the baseline conditions in these systems and increases understanding of the use of functional processes as ecological indicators in peatland..streams.
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Moore, Aaron A. "Stream macroinvertebrate communities in urbanizing watersheds in Maryland, USA." College Park, Md. : University of Maryland, 2003. http://hdl.handle.net/1903/333.
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Thesis (M.S.) -- University of Maryland, College Park, 2003.Thesis research directed by: Dept. of Entomology. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
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Watson, Troy Norton. "The structuring of aquatic macroinvertebrate communities within cave streams." Thesis, University of Canterbury. Biological Sciences, 2010. http://hdl.handle.net/10092/6513.
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The unusual environmental conditions within caves provided unique opportunities for developing an understanding of ecosystem processes. However, relatively few studies have been conducted on the ecology of New Zealand cave systems. The primary aim of this research was to investigate changes in aquatic invertebrate communities along a longitudinal gradient from the surface into caves and investigate the fundamental drivers of cave communities. This study was carried out in three streams (two in pasture catchments and one in a forested catchment) flowing into caves in the Waitomo region, North Island, New Zealand. In order to address these aims I carried out a longitudinal survey of 12 sites in each stream, an experimental manipulation of food, and an isotopic study of a single stream. The longitudinal survey of the three cave streams revealed light intensity as well as algal and CPOM biomass all decreased significantly from outside the caves into caves. In contrast, water temperature, dissolved oxygen, stream width, depth, and velocity did not vary significantly with distance into caves. Benthic aquatic macroinvertebrate communities within the caves were a depauperate subset of surface communities, appearing to be structured by gradients in resources and colonisation through drift. However, some invertebrate taxa (primarily predators) were rarely found within caves, further suggesting that resource gradients were structuring cave communities. Surprisingly, the densities of some collector-browsers (primarily mayflies) increased within cave streams relative to surface densities. This may be due to a decrease in competition and predation, flexible feeding strategies, and high drift propensity. However, the benthic densities of most taxa within the caves appeared to be related to drift densities. Although surface forest and pastoral stream communities differed in community composition and density 32 meters within the caves invertebrate community diversity and density became similar, although specific taxa within communities varied. This convergence was attributed to similar environmental gradients within the caves. The resource addition experiment (adding leaf packs) indicated that cave streams were resource limited; the addition of leaves produced communities of similar richness and density across the environmental gradient. The isotopic survey suggested cave stream invertebrate communities were reliant upon similar basal resources to surface streams. However, within the cave epilithon appeared to be increasingly important while filamentous algae were absent. Cave
aquatic invertebrates were also found to support terrestrial predators (spiders, harvestmen, and glow-worms), presumably increasing the abundance and diversity of terrestrial cave communities. In conclusion, aquatic cave communities were reliant upon surface derived resources and consequently strongly linked to surface land-use and managerial practices.
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Chan, King-tung, and 陳勁東. "Multivariate analysis of benthic macroinvertebrate communities of HongKong streams." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1996. http://hub.hku.hk/bib/B31213911.
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Reynolds, Christopher David. "The effects of coal mine closure on macroinvertebrate communities." Thesis, Nottingham Trent University, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.341279.
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Hilton-Jones, David. "Macroinvertebrate communities inhabiting surface mine wetlands of southwestern Virginia." Thesis, Virginia Tech, 1994. http://hdl.handle.net/10919/42083.
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Wetland acreage in Southwest Virginia has increased because of formation of
wetlands on relic surface mine benches. Prior to the Surface Mining Control and
Reclamation Act of 1977 (PL 95-87) once mining operations were completed the sites
were abandoned. These areas presented novel landscapes in the rugged Allegheny
Plateau physiographic region. Specifically, flat, compacted areas were created. In
microdepression of these sites wetlands have formed. This study investigates the
macroinvertebrate community associated wetlands of relic surface mining operations.
Surveys were conducted to identify what macroinvertebrates utilize these
wetlands, to determine how this community was influenced by the physio-chemical
characteristics of surface mine wetlands, and to develop design specifications for
creating wetlands for current restoration efforts. Nine wetlands were sampled four
times between July 1993 and May 1994. Seventy genera of macroinvertebrates were
identified. The wetlands represented a range of physical and chemical parameters.
The taxa richness appears to be related to these differences. Canonical
Correspondence Analysis suggests that for the nine wetlands, the macro invertebrate
taxa distribution is best explained by physical features of depth and duration of
flooding, chemical parameters of iron, manganese, and sulfate concentration,
and a biotic measure of plant litter biomass.
The findings of this study can be applied to ecological restoration. Wetland
creation can be incorporated into current surface mine reclamation projects. To
maximize the macro invertebrate community of reclamation wetlands, sites must be
positioned to avoid water quality problems, excavated to have a deeper portion which
will remain inundated during all or most of the year, and have a gradually sloping
substrate from the deepest area to the land surface. The final criteria being indirectly
related to the macroinvertebrate community by influencing the macrophyte production,
richness, and litter.
Master of Science
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Ewald, Naomi Claire. "The impact of climate change on temporary pond macroinvertebrate communities." Thesis, University of Sussex, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.494945.
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Long-term changes in climatic conditions resulting from greenhouse gas emissions have been shown to have a marked effect on many species. Less well studied are the impacts of climate change on whole communities and in particular the consequences of these changes on the interactions between species within a community. This thesis aimed to test the following hypotheses: (i) the composition of temporary pond macroinvertebrate communities will be influenced by climatic conditions affecting variables such as water depth and temperature, but these impacts will differ according to pond geology and habitat type, (ii) the impact of temperature on life history traits will be modified by the interactions between species within the community and (iii) it is possible to predict the point at which future climatic conditions will become unsuitable for temporary pond specialist species.
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Chan, King-tung. "Multivariate analysis of benthic macroinvertebrate communities of Hong Kong streams /." Hong Kong : University of Hong Kong, 1996. http://sunzi.lib.hku.hk/hkuto/record.jsp?B18037045.
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Stamp, Jennifer D. "Associations between stream macroinvertebrate communities and surface substrate size distributions." Ohio : Ohio University, 2004. http://www.ohiolink.edu/etd/view.cgi?ohiou1103232587.
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Edmonds-Brown, Veronica Roberta. "Spatial and temporal patterns in the macroinvertebrate communities in streams." Thesis, Queen Mary, University of London, 1995. http://qmro.qmul.ac.uk/xmlui/handle/123456789/1558.
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My research looked for evidence of community persistence in two suites of sites. Twenty-nine stream sites were in the Ashdown Forest of southern England and twelve streams which form part of the United Kingdom Acid Waters Monitoring Network. Benthic macroinvertebrates were collected using different methods and the species and physico-chemical data analysed. The Ashdown sites were sampled in 1989 and 1990, and the data collected was compared with previous studies and an analysis made of community persistence over a period of thirteen years. Persistence was assessed using measures of similarity and rank correlation coefficients. The data showed that several physico-chemical factors, in particular stream pH, were related to the structure of the benthic communities. Summer temperatures and stream discharge were also significantly associated with the patterns obtained. Using multivariate methods, TWINSPAN, DECORANA and CANOCO, spatial patterns were discerned. Comparisons of the two previous surveys and my own data showed that sites with low pH, low summer temperatures and low discharge had consistent spatial patterns. The United Kingdom Acid Waters Network stream sites were originally chosen for their susceptibility to acidification and are located in different geological and geographical parts of the UK. The same persistence measures were used as for the Ashdown data and, although there was greater variability, similar underlying patterns were found. Using the same methods the Ashdown and UKAWMN sites were then analysed together.
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Machado, Ana Luísa Felgueiras de Brito. "The effects of wildfire on lotic macroinvertebrate communities in Portugal." Doctoral thesis, Universidade de Aveiro, 2015. http://hdl.handle.net/10773/14539.
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Doutoramento em BiologiaThe effects of wildfires in Mediterranean lotic communities are still poorly documented. Despite some progress in recent years, the published data refer mainly to studies conducted in North America, with little information on European rivers. Given the importance of regional geographic context, both on the effects of fire and on the resilience of the communities, the gap in the biogeographical knowledge represent a limitation to the implementation of appropriate management measures. This thesis consists in a systematic study of the effects of fire on the macroinvertebrate communities of streams of North and Central Portugal. A chronosequence survey was conducted in order to analyze long-term effects of wildfires (1-18 years) and provide chronological information on the ecological recovery of macroinvertebrate communities. The results indicated that the macroinvertebrate communities recover in abundance and taxa richness and in terms of community structure about two years after the fire impact. A short-term survey was also carried out, where the initial response of macroinvertebrates to fire disturbance was documented, in streams recently affected by wildfires. The parameters analyzed were compared with reference sites without fire impact for the last 20 years. In all sampling periods, lower abundance and lower species richness were recorded in impacted streams, and differences in community structure were found between burnt sites and reference sites. In our study, both on long -term and short-term surveys, the environmental features that conditioned the response of biological communities were evaluated. River size, the extent of the burnt area, conductivity, along with channel characteristics and riparian vegetation, were considered determinant in the response of macroinvertebrates communities to fire impact, and can influence the susceptibility of stream ecosystems. We also analyzed the data of the short-term survey on a trait approach. Differences on functional diversity and on frequency of several trait modalities were analyzed. Specific differences in the food group and reproductive strategies between burned and not burned sites were recorded. Despite the unequivocal negative impact of wildfire on macroinvertebrate communities of Portuguese streams, the recovery seems to be rapid, demonstrating their resilience to this type of disturbance.
Os efeitos dos fogos nas comunidades lóticas mediterrânicas estão ainda mal documentados. Apesar do progresso verificado nos últimos anos, os dados publicados referem-se principalmente a estudos efetuados na América do Norte, sendo escassa a informação relativa aos rios Europeus. Dada a importância do contexto geográfico regional, quer nos efeitos do fogo no meio ambiente quer na resiliência das comunidades, a lacuna no conhecimento biogeográfico representa uma limitação à implementação de medidas de gestão adequadas. A presente tese consiste um estudo sistemático dos efeitos do fogo nas comunidades de macroinvertebrados dos ribeiros do Norte e Centro de Portugal. Foi analisada uma cronosequência para averiguar o efeito do fogo numa escala temporal mais alargada (1 a 18 anos) providenciando informação cronológica sobre a recuperação ecológica das comunidades de macroinvertebrados a longo prazo. Os resultados indicaram que as comunidades de macroinvertebrados recuperam em abundância, riqueza taxonómica e em termos de estrutura das comunidades cerca de dois anos após o impacto Num estudo a curto prazo, em ribeiros recentemente afetados por fogos florestais, foi documentada a resposta inicial dos macroinvertebrados à perturbação pelo fogo e os parâmetros analisados foram comparados com locais de referência onde não ocorreram fogos nos últimos 20 anos. Em todos os períodos amostrados registou-se menor abundância e menor riqueza específica nos ribeiros impactados, bem como diferenças ao nível da estrutura das comunidades entre locais ardidos e os locais de referência. Tanto no estudo a longo prazo como no estudo a curto prazo, foram avaliados os fatores ambientais que condicionaram a resposta das comunidades biológicas. O tamanho do rio, a extensão da área ardida, condutividade, bem como as características do canal e da vegetação ripária, são determinantes na resposta dos macroinvertebrados ao impacto do fogo, e podem influenciar o grau de susceptibilidade dos ecossistemas lóticos. Foram ainda analisados os resultados dos levantamentos a curto prazo numa abordagem do ponto de vista funcional. Foram analisadas as diferenças ao nível da diversidade funcional e ao nível da frequência das várias características funcionais dos organismos. Foram registadas diferenças pontuais em termos do grupo alimentar e estratégias de reprodução, entre locais ardidos e não ardidos. Apesar do inequívoco impacto negativo do fogo nas comunidades de macroinvertebrados aquáticos, a recuperação parece ser rápida, demonstrando a sua resiliência perante este tipo de perturbação.
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Stamp, Jennifer. "Associations between stream macroinvertebrate communities and surface substrate size distributions." Ohio University / OhioLINK, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1103232587.
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Tolonen, K. (Katri). "Taxonomic and functional organization of macroinvertebrate communities in subarctic streams." Doctoral thesis, Oulun yliopisto, 2018. http://urn.fi/urn:isbn:9789526217673.
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Abstract Ecological research based on both species and their traits help us to understand the main mechanisms and environmental factors structuring biological communities. In general, variation in community composition is thought to be a consequence of both stochastic and deterministic factors. In stream ecology, the traditional view has been that the local habitat conditions pose a strong environmental filter that selects only species with the right functional traits into the local communities. However, recent studies on streams have also suggested that the responses of species to environmental gradients may be independent of those of other species due to stochastic factors, such as species dispersal, which then result in more continuous communities along environmental gradients. The aim of this thesis was to explore the relative importance of the deterministic and stochastic factors in the structuring of taxonomic and functional trait-based macroinvertebrate communities in streams in a high-latitude catchment by comparing the variation in these community facets along environmental and spatial gradients. Also, the relationship between environment and the functionally-defined communities was explored closely. The results indicated how the taxonomic composition of the communities may be more closely related to the stochastic and dispersal-related factors, whereas the functional composition of the communities may be more closely related to the deterministic environmental filtering processes. However, the overall structure of the communities seems to be strongly controlled by the variation in environment, although the heterogeneous and harsh conditions of the streams may preclude the formation of predictable community types. Nonetheless, some noticeable responses of different traits to different environmental factors were found, suggesting that definable functional trait-environment relationships may be discovered if key traits of the species can be identified. Overall, these findings underline the benefits of describing both taxonomic and functional-based communities when exploring the mechanisms behind the structuring of macroinvertebrate communities. The results also have applications for conservation practices. Conservation efforts should focus on varying environmental conditions in order to cover all aspects of macroinvertebrate community variationTiivistelmä Lajeihin ja lajien toiminnallisiin lajiominaisuuksiin pohjautuva ekologinen tutkimus tuo uutta tietoa biologisten yhteisöjen taustalla vaikuttavista tekijöistä. Yleisesti yhteisöjen rakentumiseen vaikuttavat niin deterministiset kuin stokastiset ympäristössä vaikuttavat tekijät. Virtavesiyhteisöjen on perinteisesti ajateltu rakentuneen niin sanottujen ympäristösuodattimien mukaisesti, jolloin ympäristön vaihtelu suodattaa tietynlaisiin ympäristöihin vain lajit, joilla on tarvittavat ominaisuudet paikalla selviytyäkseen. Useat viimeaikaiset tutkimukset ovat kuitenkin osoittaneet virtavesiyhteisöissä elävien lajien esiintymisen vaihtelevan ympäristössä myös itsenäisesti erilaisista stokastisista, kuten lajien dispersaaliin vaikuttavista, tekijöistä johtuen. Tässä väitöstutkimuksessa tutkin näiden determinististen ja stokastisten ympäristötekijöiden suhteellisia vaikutuksia taksonomisesti ja toiminnallisesti luokiteltujen pohjaeläinyhteisöjen rakentumiseen pohjoisissa virtavesissä. Myös yksittäisten lajiominaisuuksien ja toiminnallisten yhteisöjen suhde pohjoisten virtavesien ympäristöolosuhteisiin oli tarkastelun alla. Tutkimuksen tulokset antoivat viitteitä siitä, että ympäristössä toimivat stokastiset ja lajien dispersaaliin liittyvät tekijät vaikuttaisivat voimakkaammin taksonomisesti luokiteltujen yhteisöjen vaihteluun, kun taas toiminnallisesti luokitellut yhteisöt vaikuttaisivat rakentuneen enemmän determinististen ympäristöprosessien mukaisesti. Kokonaisuudessaan yhteisöt vaikuttaisivat kuitenkin rakentuneen voimakkaasti vaihtelevien ympäristöolosuhteiden ohjaamana, ja tämä vaihtelu voi estää selkeästi ennustettavien yhteisörakenteiden synnyn. Muutamia selkeitä lajiominaisuusvasteita kuitenkin löytyi, mikä antaa viitteitä ennustettavissa olevien toiminnallisten yhteisöjen olemassaolosta, mikäli yhteisöjen menestymisen kannalta merkittävimmät lajiominaisuudet vain osataan määrittää. Nämä tulokset osoittavat, miten sekä taksonomisesti että toiminnallisesti luokiteltujen yhteisöjen käyttäminen rinnakkain yhteisöekologisissa tutkimuksissa voi auttaa selventämään yhteisöjen synnyn taustalla vaikuttavia tekijöitä. Tuloksilla on merkitystä myös virtavesiyhteisöjen suojelun kannalta. Suojelutoimenpiteet tulisi kohdistaa kattamaan ympäristöolosuhteita laajasti, jotta ympäristöolosuhteiden mukaan vaihtelevat yhteisöt tulisivat parhaalla mahdollisella tavalla katetuiksi
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Carlson, William E. "Evaluating hydrologic controls on fish and macroinvertebrate communities in Ohio's western Allegheny Plateau." Ohio : Ohio University, 2006. http://www.ohiolink.edu/etd/view.cgi?ohiou1149193823.
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Arthur, Jarred Bradley. "The influence of upstream forest on macroinvertebrate communities in pastoral landscapes." Thesis, University of Canterbury. School of Biological Sciences, 2010. http://hdl.handle.net/10092/4925.
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The conversion of native forest to agricultural land has been an on-going issue threatening the health of New Zealand’s freshwater systems. However, despite the fact that this has been occurring since early European settlement, our understanding of the mechanistic relationships between riparian vegetation and stream condition are poorly developed. This research investigated: (i) how forests affect downstream benthic macroinvertebrate communities in pasture and the environmental factors driving community change; (ii) how upstream forest size impacted the rate of change in downstream environmental drivers and associated macroinvertebrate community structure; and (iii) whether the addition of coarse particulate organic matter (a single potential driver of forest community structure) can reset community structure to that of a forested state. Physico-chemical conditions, basal energy resources, and macroinvertebrates were surveyed in several New Zealand headwater streams.
At Mount Egmont National Park, 10-12 sites were surveyed across a longitudinal forest-pasture gradient in each of five streams flowing from continuous forest to dairy farmland. My results showed that forests can have marked effects downstream. From the forest edge, water temperatures increased consistently, with a rise of approximately 0.2ºC per 100 m of downstream distance. By contrast, coarse particulate organic matter (CPOM) decreased rapidly downstream of the forest, however, low levels of “forest-derived” CPOM were still present 300m downstream from the forest edge. These environmental changes drove significant shifts in macroinvertebrate community structure. Moreover, pasture communities were
markedly different from those in forest, despite being only 100 m from the forest edge. In particular, total macroinvertebrate and EPT richness and densities decreased,
and communities shifted from evenly distributed allochthonous-based communities to autochthonous-based communities, highly dominated by molluscs (e.g., Potamopyrgus spp.)
Subsequent surveys of 6-8 sites across a longitudinal forest-pasture gradient in each of eleven streams flowing from forest fragments of different sizes into grazed
pastures throughout the Canterbury region, indicated that stream temperature increased more rapidly downstream of small- and medium-sized fragments, than larger fragments. A Berger-Parker dominance index also indicated that macroinvertebrates responded principally to water temperature, with communities being more highly dominated by temperature-tolerant molluscs in streams flowing from small-sized forest fragments.
Several headwater streams in Canterbury were also highly retentive, with marked CPOM rarely exported beyond 50 m downstream of the forest. Experimental additions of leaf litter to the pasture reaches of the same streams dramatically increased amounts of stored benthic CPOM. Although non-significant, trends indicated that EPT and shredder densities increased at litter addition sites, providing promise that CPOM can function as a mechanism directly enhancing healthy stream communities. My findings support the contention that when the replanting of entire
stream reaches is infeasible, the use of riparian management strategies which focus on the planting of intermittent patches along stream banks can potentially improve stream habitat and community health downstream.
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Verkaik, Iraima. "Wildfire effects on macroinvertebrate communities in Mediterranean streams / Efectes dels incendis forestals sobre las comunitats de macroinvertebrats en rius Mediterranis." Doctoral thesis, Universitat de Barcelona, 2010. http://hdl.handle.net/10803/1450.
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Wildfire effects on macroinvertebrate communities have not been intensively studied in other areas than the Western US, and the results in fire prone areas like NE Mediterranean and SE Australia are scarce. In this study, Mediterranean streams (both fire affected and control) presented the highest dominance of r-strategy taxa, which are characterized by their high resilience. However, three years after fire, the indirect effects of the riparian canopy removal was still significant in these streams. Located in the same burned catchment, severely canopy affected area of the Vall d'Horta stream showed high aquatic vegetation cover compared to intact canopy cover, which showed, in turn, a high leaf litter cover percentage. Although differences in organic cover were significant in the macroinvertebrate community structure and turnover, hydrology was also a very important factor that marked the succession of communities along the year in both reaches. In the Mediterranean region, our studies conclude that midterm effects of fire on macroinvertebrate communities (up to 5 years) showed the importance of yearly precipitation in their response, and important differences in macroinvertebrate community dynamics were found depending if the year was wet or dry. We conclude that macroinvertebrate communities that live in Mediterranean climate streams showed in general high resilience to fire, because they usually have to cope with other severe disturbances like flooding and drought.The results obtained in this study indicate that other disturbances like droughts and floods can modulate the severity of the responses of the macroinvertebrate communities. In general, as in other biomes, post-fire precipitations are the most severe indirect effects where a large input of nutrients and dramatic habitat change takes place. In the Mediterranean catchments usually the big flood occurs few weeks after the wildfire, while in the other studied biomes the effects could be delayed by drought (SE Australia) or by the hydrologic characteristics from the stream itself (NW USA). Furthermore, if all these disturbances will come more often and together in the future, the presence of many species may be compromised, especially those that now are not found or found in low numbers in the dry years.
Los efectos de los incendios forestales en las comunidades de macroinvertebrados han sido intensamente estudiados en el oeste de los Estados Unidos. Otras áreas donde el fuego es también un factor recurrente, como por ejemplo en el noreste del Mediterráneo y sureste de Australia, los estudios son muy escasos. En este contexto, el principal objetivo de este trabajo fue estudiar los efectos a mediano plazo de los incendios forestales sobre las comunidades de macroinvertebrados de los ríos mediterráneos y comparar los resultados con los de otros biomas.
Después del incendio del 2003 que afectó el Parque Natural de Sant Llorenç en Cataluña se estudiaron las respuestas a corto y mediano plazo de las comunidades de macroinvertebrados de ríos en cuencas quemadas y cuencas establecidas como control. En general, las comunidades de macroinvertebrados (tanto de los ríos afectados por el fuego como los ríos control) presentaron un dominio de los taxones de estrategia "r", que caracteriza la frecuencia de perturbaciones de estos ríos y asimismo su alta resiliencia. Tres años después del incendio, los efectos indirectos del fuego se compararon en dos localidades de la Vall d'Horta afectadas de manera diferente en la cobertura de ribera. La eliminación del bosque de ribera generó diferencias significativas en la cobertura orgánica que a su vez fueron importantes para la estructura y temporalidad de la comunidad de macroinvertebrados. Sin embargo, la hidrología también fue un factor muy importante que marcó la sucesión de comunidades a lo largo del año. En este sentido, los efectos a mediano plazo después de un incendio forestal en las comunidades de macroinvertebrados (hasta 5 años) mostraron la importancia de la precipitación anual en su respuesta, y las mayores diferencias en la dinámica de la comunidad de macroinvertebrados se encontraron dependiendo de si el año había sido húmedo o seco. En conclusión, las comunidades de macroinvertebrados que estos ríos mediterráneos mostraron en general una alta resistencia al fuego, ya que por lo general tienen que hacer frente a otras perturbaciones comunes como las inundaciones y las sequías.
La comparación de estos resultados con otros biomas indica que otras alteraciones como las sequías y las inundaciones pueden modular la severidad de las respuestas de las comunidades de macroinvertebrados. En general, como en otros biomas, las precipitaciones después de un incendio son los efectos indirectos más graves en un gran aporte de nutrientes y con el aumento de la erosión se genera un cambio dramático del hábitat. En las cuencas del mediterráneo por lo general la gran inundación post-incendio se produce pocas semanas después del incendio, mientras que en comparación con los otros biomas estudiados los respuestas podrían ser retrasadas por la sequía (sureste Australia) o por las características hidrológicas de los ríos (noroeste de los Estados Unidos). Se prevé que estas perturbaciones incrementarán tanto la recurrencia como la intensidad ya que ocurrirán al mismo tiempo, en este contexto la presencia de muchas especies y la resiliencia puede verse comprometida, sobre todo las que ahora no se encuentran o se encuentran en baja abundancia en los años secos.
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Veenstra-Quah, Anneke Alison, and mikewood@deakin edu au. "The impact of stresses imposed on macroinvertebrate communities in two urban streams." Deakin University. School of Biological and Chemical Sciences, 1999. http://tux.lib.deakin.edu.au./adt-VDU/public/adt-VDU20050815.102219.
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The aim of the project was to determine factors which explain the distribution of macroinvertebrates in two Melbourne streams both drastically affected by urbanisation. A detailed description is given of Dandenong Creek, flowing through the south-eastern suburbs, and Darebin Creek, in the northern suburbs, emphasising stream features likely, or known, to influence the drift and benthic fauna.
Faunal sampling was carried out in Dandenong Creek from June 1992 until July 1993, and in Darebin Creek from February 1995 until March 1998. Physicochemical parameters were also recorded. The collected data, together with previously existing data, were analysed using multivariate analyses: non-metric multi-dimensional scaling (NMDS); analysis of similarities (ANOSIM); matching biotic and abiotic variables using BIOENV, and principal component analysis (PCA). Various biotic and diversity indices were calculated in an attempt to identify the major factors responsible for the failure of the fauna to recover from previously more seriously degraded water quality.
The contribution of drift to the colonisation potential in Dandenong Creek appeared to be impacted by retarding basins, underground barrel-draining and channelization. Results also indicated that increased conductivity adversely affected the fauna in the lower reaches of Dandenong Creek. It was concluded that in Darebin Creek, high nutrient levels, as well as other pollutants, had resulted in low macroinvertebrate diversity in both the drift and benthos.
If, as this study suggests, faunal diversity is a valid measure of stream health, the following factors need to be addressed for catchment-wide, stream management: lack of riparian zone vegetation (increasing bank erosion and making the benthic habitat unstable, with greater temperature variability); control of stormwater runoff (flow variability, increased conductivity, nutrient levels, sediment loads, sewage effluent, industrial discharges and heavy metals), and to modify retarding basins to increase stream continuity.
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Fletcher, Rachael. "Diagnostic capacity of laboratory mesocosms, response of macroinvertebrate communities to sediment contamination." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq38239.pdf.
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Gallacher, D. "The use of benthic macroinvertebrate communities as biomonitors in Hong Kong streams." Thesis, Hong Kong : University of Hong Kong, 2000. http://sunzi.lib.hku.hk/hkuto/record.jsp?B22227349.
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Chambers, Catherine P. "Potential impacts of transgenic crop residues on macroinvertebrate communities in agricultural streams /." Available to subscribers only, 2008. http://proquest.umi.com/pqdweb?did=1650504151&sid=1&Fmt=2&clientId=1509&RQT=309&VName=PQD.
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Culler, Lauren Elizabeth. "Macroinvertebrate predators and their role in shaping freshwater communities in constructed wetlands." College Park, Md.: University of Maryland, 2008. http://hdl.handle.net/1903/8543.
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Thesis (M.S.) -- University of Maryland, College Park, 2008.Thesis research directed by: Dept. of Entomology. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
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Bonjour, Sophia. "Influence of Fishes on Macroinvertebrate Communities in Prairie Stream Permanent Water Refugia." OpenSIUC, 2018. https://opensiuc.lib.siu.edu/theses/2348.
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Physical factors, such as hydrologic variability, are major structuring forces of prairie stream communities. Macroinvertebrate and algae densities can both decrease sharply in response to floods and drying. Less is known about the influences of biological factors, such as fishes. The influence of fishes on macroinvertebrate communities varies with environmental factors and other biologic interactions, ranging from neutral to strong negative effects on some populations, and the strength of these interactions sometimes appear linked to hydrology. Drying intermittent streams leave permanent water refugia that may be hotspots for interactions between fishes and invertebrates. Effects of fishes on macroinvertebrate communities may vary with invertebrate life cycle stages (e.g., larvae, emerging adults, colonizing adults). I examined macroinvertebrate communities (benthic and emerging) and algal biomass across a range of permanent stream pool sites at Konza Prairie Biological Station with naturally varying densities of fishes. I also manipulated fish densities in a mesocosm experiment to address how fishes may also be effecting colonization during recovery from hydrologic disturbance. Fish biomass had a negative impact on invertebrate abundance, but not biomass or taxa richness, in natural pools. Total fish biomass was not correlated with total insect emergence in natural pools, but orangethroat darter (Etheostoma spectabile) biomass was inversely correlated with emerging Chironomidae biomass (r2 = 0.43, p = 0.047) and individual midge body size (r2 = 0.61, p = 0.014). Predatory fish biomass and a date interaction appeared in top linear models, indicating fish may also delay insect emergence from natural pools. Fish presence reduced abundance of colonizing insects (p < 0.001) and total invertebrate biomass (p = 0.001) in mesocosms. Mesocosm insect communities in pools without fishes were characterized by more Chironomidae, Culicidae, and Corduliidae (p < 0.001 for all). Chlorophyll-a increased between sampling dates in mesocosms, but did not differ between treatments. Not all life stages showed the same response to fishes, illustrating the need for understanding life histories in order to interpret the influence of fishes. Understanding how fishes in prairie streams affect ecosystem structure and function is critical for conservation and management of remaining grassland streams. Results suggest fishes can influence colonization and community structure in prairie stream pools, which serve as important refugia during hydrologic disturbance and source areas for colonists during recovery.
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Rantala, Heidi Marie. "Glacial legacy effects on tundra stream processes and macroinvertebrate communities, North Slope, Alaska." Thesis, [Tuscaloosa, Ala. : University of Alabama Libraries], 2009. http://purl.lib.ua.edu/53.
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Mullen, Caroline. "An investigation into the effects of drought and drought recovery on macroinvertebrate communities." Thesis, University of Birmingham, 2016. http://etheses.bham.ac.uk//id/eprint/7137/.
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The effect of drought on freshwater ecosystems is a growing environmental concern. This study aimed to determine the effect of the supra-seasonal 2010-2012 drought on the macroinvertebrate communities and functional feeding groups (FFG) of chalk streams. Three rivers were sampled during and after the drought, three sites were analysed on each river, a perennial control site, a dewatering site (shallow during drought) and a rewetted site (dry during drought). All wetted sites were sampled for macroinvertebrates, algae, velocity and depth monthly. In addition an in-situ experiment investigated grazing rates in dewatering, rewetted and perennial sites and a mesocosm experiment investigated the effect of reduced water velocity and temporary drying on grazing function and macroinvertebrate mortality. Macroinvertebrate data were analysed for structural and functional changes in communities and algal data were analysed for changes of biomass both during drought and recovery. Both found rapid recovery post-drought with high incidence of resilience in the macroinvertebrate communities. Functional recovery was determined by investigating grazing rates in dewatering, rewetted and perennial sites. Algal and macroinvertebrate biomass, and grazing function recovered within a month of rewetting. Despite a rapid recovery of overall biomass and grazing function, FFG results showed delayed effects, and four months following drought differences were still present. Mesocosm experiments showed that macroinvertebrate mortality increased due to dewatering for some species, however slower velocity had little effect. Thus, this study showed that ecological function can return despite changes to macroinvertebrate community structure, indicating that functional redundancy promotes the resilience of chalk stream communities to drought.
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Washko, Susan. "The Macroinvertebrate and Fish Communities of In-Stream Beaver Ponds in Northeastern Utah." DigitalCommons@USU, 2018. https://digitalcommons.usu.edu/etd/7395.
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Beavers were virtually extirpated from North America during the fur trade, but populations have since recovered. Dams built by recolonizing beaver alter stream habitat by forming deep, slow ponds within the streams. Such changes to the habitat is likely to have consequences for organisms such as macroinvertebrates and fish. The objective of this study was to identify the differences in the macroinvertebrate and trout community in beaver ponds and lotic (e.g. flowing reaches of a stream) reaches in tributaries to the Logan River in northeastern Utah. The macroinvertebrate community of beaver ponds had fewer species, fewer numbers, and lower biomass of macroinvertebrates compared to lotic reaches. Macroinvertebrates that consume leaf litter and predators that prey on other macroinvertebrates characterized beaver pond macroinvertebrate communities. In contrast, lotic reaches contained macroinvertebrates that consume algae and feed on particles floating through the water column. Macroinvertebrates in lotic reaches were morphologically adapted to cling to rocks in the streamflow, while those in beaver ponds were adapted to living within the fine sediment.
Bonneville cutthroat trout collected from lotic reaches were larger than those collected from beaver ponds, while the opposite was true for brown trout collected from lotic reaches. I also found that short-term and long-term diets of both brown trout and Bonneville cutthroat trout were similar between trout caught in beaver pond and lotic reaches. Finally, I found that growth rates of trout were also similar between the two habitats. In conclusion, the structure and function of macroinvertebrates, which are dependent on small-scale habitat features, were more affected by inclusion of beaver ponds to the stream network. Conversely, trout collected from beaver ponds and lotic regions were similar in growth and diet. Considering that beavers are used as a common restoration tool, further studies on the effects of beaver on stream communities is essential.
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Bernard, Aaron Michael. "Geospatial Modeling of Forest Road Networks and Their Effect on Stream Macroinvertebrate Communities." Thesis, Virginia Tech, 2006. http://hdl.handle.net/10919/33338.
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Road construction and maintenance throughout the country continues to be one of the largest contributors of sediment pollution to aquatic systems. Though impacts of road networks on aquatic systems can be potentially severe, little work has been performed to evaluate the effect that road spatial location within a watershed has on water quality. To address this issue from a quantitative perspective, a â Road Impact Factorâ protocol was designed to identify potential erosion-prone segments of road networks based on road gradient, spatial location based on hydrologic flow length, surface composition, and water control installations. The protocol was developed for two regions in Central Idaho and Eastern Oregon. We then used the hydrologic travel time procedure, developed for use in the Hydrologic Engineering Center Hydrologic Modeling System (HEC-HMS) runoff and routing model, in order to characterize the spatial distribution of potential road runoff impacts within the study areas. Ten macroinvertebrate metrics sensitive to sedimentation (i.e. % Intolerant Taxa, Hilsenhoff Biotic Index, etc.) were analyzed to test the significance of the spatial distribution of Road Impact Factors. These 10 metrics were analyzed under the hypothesis that values will be lower for those study areas that have a higher degree of road impact and a lower distance between the road segments and stream reaches. Results of a quadrant analysis and hierarchical clustering analysis showed hypothesized trends for several metrics in Idaho, though the trends were not strong. No trends were observed in Oregon. The variability in results is likely due to limitations of the input datasets.Master of Science
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Weaver, Meghan C. "Effects of Copper Sulfate Application on Zooplankton and Macroinvertebrate Communities in Upground Reservoirs." Bowling Green State University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1339094079.
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Carlson, William E. "Evaluating Hydrologic Controls on Fish and Macroinvertebrate Communities in Ohio’s Western Allegheny Plateau." Ohio University / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1149193823.
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Thrush, Hood Mariah A. "Seasonal Variation of Chemistry, Hydrology, and Macroinvertebrate Communities within Acid Mine Drainage Streams." Ohio University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1545254097494315.
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Thomas, Stephen Michael. "Consequences of riparian land use for macroinvertebrate communities and trout in upland streams." Thesis, Cardiff University, 2013. http://orca.cf.ac.uk/57732/.
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1. Climate change is predicted to negatively impact ecosystems globally. Freshwaters are particularly susceptible, due to thermal and hydrological sensitivity and poikilothermic fauna. Such change may ultimately imperil ecosystems service provision. Adaptation schemes that limit ecological and economic impacts are therefore widely advocated. The major management action recommended for rivers is restoration of “buffer strips” of riparian tree cover, which can lower stream water temperatures, and should therefore protect thermally sensitive species, including economically important salmonid fish (Family: Salmonidae). 2. Despite thermal consequences being well-quantified, community-wide biotic responses to restoration remain unexplored. Such ecological consequences may ultimately govern the efficacy of this measure in protecting focal species, but there is limited evidence available from which to predict restoration outcomes and inform management efforts. 3. Using 24 upland streams, this thesis assessed ecological consequences of differential catchment tree cover on stream communities. Using surveys and experimentation, the project assessed the role catchment afforestation in mediating the importance of terrestrial resource subsidies to stream food webs, structuring macroinvertebrate communities, and supporting salmonid fish. 4. Several lines of evidence indicated that wider catchment tree cover controls the functional composition of stream communities, by mediating availability of terrestrial resources. However, buffer strips did not approximate the effects of wider broadleaf forest, and supported communities that were functionally indistinguishable from streams draining unafforested moorland. Unexpectedly, catchment broadleaf cover did not ultimately affect salmonid populations, contrary to expectations. 5. In combination, these results contribute to the understanding of land use effects on stream communities, and provide clear evidence needed to guide future management efforts. These findings suggest two distinct adaptation options: restoration of buffer strips should be able to confer benefits to fish populations, by offsetting thermal impacts without jeopardising food availability. However, re-instatement of wider broadleaf forest could potentially re-establish woodland stream communities.
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O'Connor, Eve. "Long-term Spatial and Temporal Variability of Benthic Macroinvertebrate Communities: Implications for Bioassessment of Lotic Systems." VCU Scholars Compass, 2010. http://scholarscompass.vcu.edu/etd/2064.
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The structure and composition of benthic macroinvertebrate communities can vary spatially and over time. Spatial and temporal variation along a stream has many implications for population and community dynamics, which may influence bioassessment programs. I examined variability in the benthic community of eight streams within the Polecat Creek, Virginia watershed. These streams vary in size from 1st to 4th order. The streams were sampled once every season for eleven years using standard bioassessment protocols. Macroinvertebrates were sampled from both sediment and submerged wood habitats at each site. The coefficient of variation (CV) was used to quantify among season, among year and among site variability of eight community metrics from both the sediment and wood samples. ANOVAs were calculated using Tukey post-hoc test to determine if there were statistically significant differences in taxonomic richness and mean CV values across seasons, years and sites for both sediment and wood samples. Sorenson’s Quotient of Similarity was used to examine the extent of differences in the taxonomic composition of the macroinvertebrate communities among the four seasons over the 11 years of the study and among the 8 sampling sites. A high amount of variability was observed among seasons, sites and years. A wide range of CV values was observed among community metrics, with certain metrics exhibiting low overall mean CV values and others exhibiting very high overall mean CV values. It is important to understand the temporal and spatial variability of macroinvertebrates when planning biomonitoring programs.
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Kipp, Rebekah. "Impacts of an invasive benthic predator on macroinvertebrate communities in the St. Lawrence River." Thesis, McGill University, 2010. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=94911.
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Introduced exotic predators can restructure biotic communities and alter the functioning of ecosystems. The round goby Neogobius melanostomus, a Eurasian fish, has spread throughout the lower Great Lakes and, in recent years, has colonized the upper St. Lawrence River. A few studies have recorded the impacts of this predator on benthic communities in the Great Lakes, highlighting its negative effects on zebra mussels and other macroinvertebrates. In this thesis, I investigate the direct and indirect effects of the round goby on benthic macroinvertebrate communities and algae in the upper St. Lawrence River. Through an analysis of the goby's diet, I link its prey selection to observed changes in mollusc size structure and the composition of macroinvertebrates on rocky substrates. I also quantify post-invasion changes in macroinvertebrate functional feeding groups, body size of dominant taxa, and community richness, evenness and abundance. Finally, I present evidence of a trophic cascade an increase in algal biomass driven by the negative impacts of gobies on algivorous macroinvertebrates. These changes have significant implications for benthic community stability, ecosystem functioning, and native fishes that rely on benthic macroinvertebrates in the upper St. Lawrence River.Les prédateurs exotiques introduits peuvent restructurer les communautés biotiques et modifier le fonctionnement des écosystèmes. Le gobie à taches noires Neogobius melanostomus, un poisson eurasien, s'est répandu à travers les Grands Lacs inférieurs et, plus récemment, a colonisé la partie supérieure du Fleuve Saint-Laurent. Quelques études ont décrit les impacts de ce prédateur sur les communautés benthiques dans les Grands Lacs, en mettant l'accent sur ses effets néfastes sur les moules zébrées et les autres macroinvertébrés. Dans ce mémoire, j'étudie les effets directs et indirects du gobie à taches noires sur les communautés benthiques de macroinvertébrés et sur les algues dans la partie supérieure du Fleuve Saint-Laurent. À travers d'une analyse du régime alimentaire du gobie, je relie sa sélectivité de proies aux changements observés à la structure de taille corporelle des mollusques et à la composition des macroinvertébrés associés aux substrats rocheux. Je quantifie aussi les changements après l'invasion aux guildes alimentaires de macroinvertébrés, à la taille corporelle des taxons de macroinvertébrés dominantes, et à la richesse taxonomique, à l'égalité taxonomique et à l'abondance des communautés, suite à l'invasion du gobie. Finalement, je présente des preuves d'une cascade trophique une augmentation de la biomasse des algues causée par les impacts néfastes des gobies sur les macroinvertébrés algivores. Ces changements ont des implications importantes pour la stabilité des communautés benthiques, le fonctionnement de l'écosystème, et pour les poissons indigènes qui dépendent des macroinvertébrés benthiques dans la partie supérieure du Fleuve Saint-Laurent.
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Bonada, i. Caparrós Núria. "Ecology of the macroinvertebrate communities in Mediterranean rivers at different scales and organization levels." Doctoral thesis, Universitat de Barcelona, 2003. http://hdl.handle.net/10803/1420.
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The main objective of this work has been to determine the structure of the macroinvertebrate communities in mediterranean rivers at different scales, organization and taxonomical levels. To achieve that, an appropriated sampling methodology for macroinvertebrate studies has been developed. Physical and chemical data and riparian and habitat characteristics have been also recorded in each sampling site. At regional scale it has been studied the macroinvertebrate composition at family level in all mediterranean regions around the world: California, Mediterranean Basin, Chile, South Africa and South and South-western Australia. Convergences and divergences between regions have been established pointing out the influence of the historical and ecological factors.
At local scale the effect of the temporality (differences between permanent and temporary rivers) and habitat (differences between riffles and pools) over the macroinvertebrate community in mediterranean rivers of the world have been studied. The results demonstrate a degree the convergence in the responses to temporality and habitat, being this last factor more convergent that the former. Moreover, the effects of the temporality over habitat and vice versa have been analyzed, indicating that both are strong correlated: temporality change the habitat and habitat influence over the temporality of the reach. Both aspects have an important effect over the macroinvertebrate community at different levels of observations from richness or composition to biological traits.
Moreover, at a lower taxonomical level, caddisfly community from Spanish mediterranean rivers has been studied. A total of 91 species have been identified using larvae, pupae and adults. The distribution patters displayed by these organisms indicate that historical factors may be important for some species, although most of them have a distribution limited by ecological variables. In that sense, ecological factors associated to large (basin) or small (reach or habitat) scale are important in the caddisfly distribution. Finally, because the importance of the caddisfly as bioindicators, optimums and tolerances to several chemical variables have been obtained for all species. Moreover, a study of the effect of the pollution over the fluctuating asymmetry of Hydropscyhe exocellata populations have demonstrated that at this level, there is a strong relatio.
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Snook, Deborah Louise. "Macroinvertebrate communities in alpine glacier-fed streams : the Taillon catchment in the French Pyrenees." Thesis, University of Birmingham, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.343507.
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Brauns, Mario. "Human impacts on the structure and ecological function of littoral macroinvertebrate communities in lakes." Doctoral thesis, Humboldt-Universität zu Berlin, Landwirtschaftlich-Gärtnerische Fakultät, 2009. http://dx.doi.org/10.18452/15947.
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Das litorale Makrozoobenthos ist eine bedeutende biotische Komponente in Seen und trägt substantiell zur Biodiversität und Funktion von Seeökosystemen bei. Allerdings unterliegt das Litoral zunehmenden anthropogenen Nutzungen, deren ökologische Auswirkungen jedoch kaum quantifiziert wurden. In dieser Doktorarbeit wurde untersucht, welche Bedeutung maßgebliche Umweltfaktoren auf die Zusammensetzung des litoralen Makrozoobenthos haben, und wie sich anthropogene Nutzungen auf die Zusammensetzung und Funktion des Makrozoobenthos auswirken. Die Zusammensetzung des Makrozoobenthos wurde durch die Uferstruktur, Trophie und das hydrodynamische Regime bestimmt. Die faunistische Ähnlichkeit zwischen Habitaten war jedoch signifikant geringer als zwischen Trophiestufen, so dass die Uferstruktur, und nicht die Trophie, einen größeren Einfluss auf das Makrozoobenthos hat. Strukturelle Degradation führte zu einer Reduktion der Habitatheterogenität, was eine signifikante Verringerung der Diversität und eine signifikant veränderte Artenzusammensetzung verursachte. Infolgedessen war die Komplexität der Makrozoobenthos-Nahrungsnetze an degradierten Ufern signifikant geringer als an natürlichen Ufern. Erhöhte Wasserstandsschwankungen führten zum Ausfall von Wurzelhabitaten und der damit assoziierten Makrozoobenthos-Gemeinschaft. Schiffsinduzierter Wellenschlag führte zur Verdriftung des Makrozoobenthos von ihren Habitaten bereits bei geringen Sohlschubspannungen. Die Effekte von Wasserstandsschwankungen und schiffsinduziertem Wellenschlag wurden jedoch durch Habitate mit hoher struktureller Komplexität verringert. Mit dieser Doktorarbeit konnte ich ein mechanistisches Verständnis darüber erarbeiten, wie anthropogene Nutzungen die Wirkungsbeziehungen zwischen Umweltfaktoren und Artengemeinschaften verändern und welche ökologischen Auswirkungen dies hat. Diese Kenntnisse können als wissenschaftliche Basis zur Bewertung von anthropogenen Beeinträchtigungen des Litorals dienen.Littoral macroinvertebrates are an important biotic component of lakes by contributing substantially to the biodiversity and functioning of lake ecosystems. Humans alter the littoral and riparian areas for various purposes, but the resulting ecological impacts on littoral macroinvertebrates have not been quantified. In this thesis, I investigated the significance of key environmental factors for littoral macroinvertebrate communities and how human alterations of these environmental factors impact the structure and function of macroinvertebrate communities. Macroinvertebrate community composition was significantly related to littoral structure, trophic state and the hydrodynamic regime. The significantly higher compositional dissimilarities among habitats than among trophic state suggested that littoral structure was the more important driver of community composition. Structural degradation caused a significant reduction of habitat heterogeneity and resulted in a significant reduction of species diversity and a significant altered community composition. This caused a significant reduction of macroinvertebrate food web complexity and substantial alterations of the trophic base of the food webs. Climate-change induced water level fluctuations resulted in the loss of root habitats and the specific community associated with this habitat. Ship-induced waves had substantial direct effects, since macroinvertebrates were detached from their habitats by waves even at moderate shear stress levels. However, the impacts of water level fluctuations and ship-induced waves were mitigated by the presence of habitats with high structural complexities. This thesis provided a mechanistic understanding of how human activities alter relationships between environmental factors and biotic communities. This knowledge can be used to develop scientifically sound approaches to assess the persistent human impacts on lake ecosystems.
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Last, Jennifer L. "Impact of Specific Acid Mine Drainage Contaminants on Macroinvertebrate Communities in Southeastern Ohio Streams." Ohio University / OhioLINK, 2001. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1005080233.
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Mathers, Kate L. "The influence of signal crayfish on fine sediment dynamics and macroinvertebrate communities in lowland rivers." Thesis, Loughborough University, 2017. https://dspace.lboro.ac.uk/2134/25493.
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The spread of non-native species is a global threat and the rate at which biological invasions occur is likely to increase in the future. This thesis examines the implications of the invasive signal crayfish, Pacifastacus leniusculus (Dana), for instream communities and abiotic processes within lowland rivers in England. The potential effects on lotic macroinvertebrate communities and fine sediment dynamics are investigated at a range of spatial and temporal scales, from the examination of national long-term datasets through to short-term detailed mesocosm experiments. Interrogation of macroinvertebrate community data from three English regions was undertaken to understand the temporal and spatial extent of signal crayfish effects. Invasive crayfish had significant long-term and persistent effects on resident macroinvertebrate communities regardless of the lithology or other environmental characteristics of the region. The resultant modifications to community composition had repercussions for several widely employed freshwater biomonitoring tools which employ faunal abundance in their derivation. A reach-scale field study was undertaken at two sites, one invaded by crayfish and one which did not support populations of crayfish (control), to assess the potential contribution of signal crayfish for fine sediment dynamics (ingress, fluxes and ultimately the overall implications for sediment budgets). Reach-scale field experiments examining the effect of crayfish invasion on resident macroinvertebrate communities over a 126-day period indicated that once crayfish populations are well-established their effects are persistent. However, separating the effects of crayfish from wider macroinvertebrate community dynamics and life-history characteristics of the invader and resident taxa means that attributing the effects is far from clear. The thesis presents the results of a series of novel mesocosm experiments which examined the dynamic and two-way interactions of predator-prey relationships and potential zoogeomorphological effects of signal crayfish and the freshwater shrimp, Gammarus pulex. Signal crayfish had a significant effect on the mass of fine sediment infiltrating into the gravel matrix associated with foraging and predatory activity; however this was strongly controlled by prey availability. Finally, through the development of conceptual models, the thesis illustrates the need for greater integration of ecological and geomorphological theories, at relevant environmental scales (temporal and spatial) to achieve truly interdisciplinary research.
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Hill, Andrew C. "Assessing Linkages Among Landscape Characteristics, Stream Habitat, and Macroinvertebrate Communities in the Idaho Batholith Ecoregion." DigitalCommons@USU, 2010. https://digitalcommons.usu.edu/etd/774.
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Understanding the composition of lotic communities and the landscape processes and habitat characteristics that shape them is one of the main challenges confronting stream ecologists. In order to better understand the linkages among landscape processes, stream habitat, and biological communities and to understand how accurately our measurements represent important factors influencing biological communities, it is important to test explicit hypotheses regarding these linkages. Increasing our understanding of aquatic communities in a hierarchical context and recognizing how well our measurements represent factors structuring aquatic communities will help managers better evaluate the influence of land management practices on aquatic ecosystems, direct conservation strategies, and lead to better assessments of ecological condition.
In Chapter 2, we used spatial data, field-based habitat measurements, and macroinvertebrate community data to 1) examine the influence of landscape processes on two factors of stream habitat; maximum stream temperatures and fine sediment, and to 2) examine how well these landscape and habitat characteristics represent factors influencing gradients in macroinvertebrate community structure. The results of this study showed that spatially derived measurements may be effectively used to test hypotheses regarding landscape influences on stream habitat and that spatial data, used in conjunction with field measurements can provide important information regarding factors influencing gradients in biological communities. In addition, spatially derived measurements may provide the same or additional information regarding influences on community structure as field-based measurements, which suggests that further research should be done to assess how well our field measurements represent factors that are important in shaping stream communities.
The objective of Chapter 3 was to compare how well single field measurements and a combination of indicator variables hypothesized to be components of a single ecological processes or concept, known as a latent variable, represent thermal stress and fine sediment influences on macroinvertebrate communities. Results from this study showed that both single and latent variables explained relatively the same amount of variation in macroinvertebrate community structure. This suggests that while latent variables may have a potential to better refine how we represent ecological factors, a better basis for defining a priori hypotheses is needed before these variables can provide any additional information compared to single habitat measurements.
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Tornwall, Brett Matthew. "The role of dispersal networks in structuring biotic communities: A tale of streams and metacommunity theory." Diss., Virginia Tech, 2016. http://hdl.handle.net/10919/75004.
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Identifying the processes and mechanisms that govern communities of organisms is the main goal of community ecology. Locally operating mechanisms such as environmental filtering, in which the environment determines what species are found in a given location, as well as regional processes such as dispersal have all been identified as potential drivers of community processes. However, the relative importance of these drivers may vary temporally and spatially. In dendritic stream networks, headwater streams are isolated when compared to more centrally located mainstem stream sections. I investigated the potential for stream networks to influence the relative influence of local and regional processes via a survey and field experiment based approaches. I found that headwater streams can influence mainstem stream communities, potentially as a result of the dispersal of organisms or abiotic materials. Additionally, I demonstrated that macroinvertebrate communities in headwater streams respond more strongly to manipulations of local environment than do mainstem streams, both in terms of community composition as determined taxonomically and as functional traits. These results indicate that headwater streams may be affected differently than mainstem streams by anthropogenic activity and as such, management strategies and restorations may need to be specifically tailored to address the relative influences of local and regional processes at varying points within a stream network.Ph. D.
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Kitto, Justin. "The application of ecological theory to the remediation of macroinvertebrate communities impacted by acid mine drainage." Thesis, University of Canterbury. School of Biological Science, 2009. http://hdl.handle.net/10092/4619.
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Numerous streams on the West Coast drain catchments impacted by active or abandoned coal mining areas. Acid mine drainage (AMD) from coal mining can have significant negative effects on stream communities. Changing environmental ethics and regulations mean that mining companies are now encouraged to treat acid mine drainage to enable streams communities to recover. However, remediation efforts have not always been ecologically successful, and mining companies are seeking methods to enhance macroinvertebrate community recovery. Initially, I conducted an extensive survey of 45 streams draining the Stockton Plateau, which is the site of the largest opencast coal mine in New Zealand. I assessed physical and chemical conditions at each site as well as sampling benthic communities. This spatial survey showed streams impacted by acid mine drainage were comprised of chironomids and AMD-tolerant caddisflies such as Psilochorema and stoneflies such as Spaniocercoides. Un-impacted streams typically had a pH of ~5 and were dominated by mayflies (Deleatidium or Zephlebia). Analysis revealed that stream location within the landscape also had a significant influence on macroinvertebrate community composition. Another aspect of stream recovery is the ability of species to recolonise a stream. Therefore, I investigated the flight direction of adult aquatic insects in order to determine longitudinal and lateral flight preferences. No significant differences in flight direction were observed. I also investigated the influence of riparian habitat on lateral dispersal and found that a number of patterns were evident. Scrub vegetation supported higher densities of adult aquatic insects dispersing further from the stream, in contrast to the rapid decline in open bedrock and forest. Furthermore, a comparison between downstream drift and aerial flight showed significantly more individuals where drifting downstream, and this method is liable to provide rapid recolonisation of macroinvertebrates within connected stream networks. At the local scale, organic matter (comprising leaves bags and timber) and artificial moss cover were added to six streams to determine if organic matter and habitat availability would improve macroinvertebrate communities in manipulated streams. A series of floods during the experiment reduced taxonomic richness and density in manipulated streams. Overall, this study has shown that after AMD has been treated, the geographic position of streams within the landscape and lateral dispersal barriers may prevent streams being rapidly re-colonised. Therefore, to promote rapid re-colonisation of macroinvertebrates, stream remediation projects should be targeted at streams that either have un-impacted headwaters or tributaries. This will allow macroinvertebrates to drift in and re-colonise faster. In my experiment I did not find that organic matter significantly enhanced the macroinvertebrate community, but moss additions did provide additional habitat for macroinvertebrates. These results highlight the importance that disturbance events can have on remediation projects.
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Bunzel, Katja [Verfasser]. "Pesticide sources and landscape elements driving aquatic pesticide exposure and effects on macroinvertebrate communities / Katja Bunzel." Landau : Universitätsbibliothek Landau, 2014. http://d-nb.info/1057976210/34.
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Williams, Kristi. "Macroinvertebrate and crayfish communities in the Meramec River drainage basin an investigation at multiple spatial scales /." Diss., Columbia, Mo. : University of Missouri-Columbia, 2006. http://hdl.handle.net/10355/4580.
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Thesis (M.S.) University of Missouri-Columbia, 2006.The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file viewed on (June 27, 2007) Includes bibliographical references.
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Leung, Sze-lun. "Scale-dependent effects of spatial and temporal variability on benthic macroinvertebrate communities in Hong Kong streams /." Hong Kong : University of Hong Kong, 2002. http://sunzi.lib.hku.hk/hkuto/record.jsp?B25334542.
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Hansen, Jonathan Ford. "Long-term implications of dam removal for mesohabitat and macroinvertebrate communities in Michigan and Wisconsin rivers." Diss., Connect to online resource - MSU authorized users, 2008.
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Blackman, Rosetta Charlotte. "Environmental DNA : from detection of priority invasive species to monitoring entire macroinvertebrate communities in freshwater ecosystems." Thesis, University of Hull, 2017. http://hydra.hull.ac.uk/resources/hull:16527.
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Freshwater ecosystems are among the most threatened habitats on Earth, facing challenges from a range of anthropogenic pressures. Accurate biodiversity assessment is essential to identify these pressures prior to irreversible damage. Current monitoring techniques for freshwater systems rely heavily on capture methods to infer the status of an ecosystem. However, these methods are often inefficient at detecting and identifying all species at a site and often miss those in low abundance. Emerging molecular methods such as environmental DNA (eDNA) could be a “game changer” for freshwater biodiversity monitoring. This thesis focuses on the application of eDNA for detection of invasive non-native species (INNS) and whole macroinvertebrate community assessment. Firstly, targeted eDNA PCR assays were developed for four priority freshwater INNS, and validated in mesocosm experiments and field trials. Targeted (PCR and qPCR) and passive (metabarcoding) eDNA approaches were then compared to traditional methods for detecting quagga mussels, Dreissena rostriformis bugensis. The targeted approaches were the most sensitive for detection of quagga mussels at low densities and both qPCR and metabarcoding showed correlations with mussel density. The power and utility of eDNA metabarcoding for detecting rare or unexpected taxa was then demonstrated by passive detection of a new INNS, Gammarus fossarum, in UK rivers. Finally, metabarcoding of both bulk DNA and eDNA from water and sediment was compared to the traditional method of macroinvertebrate sampling, to evaluate the potential of emerging molecular methods for ecological assessment. The results show metabarcoding approaches are not suitable to retrofit or replace existing methods of assessment, but provide an exciting opportunity for greater taxonomic identification and have the ability to detect a combination of taxa across groups, some of which are not utilised in current ecological assessment methods. This work has demonstrated a huge potential for eDNA methods to be applied to INNS monitoring and further our ability to carry out complete biodiversity assessment of waterbodies.
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Thomas, Rhodri James. "The form and stability of alluvial riverbeds, and their effects on macroinvertebrate communities across Great Britain." Thesis, Cardiff University, 2018. http://orca.cf.ac.uk/111456/.
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The sustainable functioning of macroinvertebrate communities forms the basis of many of the vital ecosystem services provided by rivers, yet these communities are amongst the most stressed on the planet and predictions show these stresses increasing in the future. At a conceptual level, macroinvertebrate community composition is inextricably linked to the riverbed sediment in which they reside, although evidence of these links is largely confined to descriptive or small-scale studies. Robust predictions of the response of these communities to future change are urgently needed but this first requires a better understanding of the interaction between physical and ecological processes across larger spatial and temporal scales. Using national scale monitoring data for rivers across Great Britain, this study tested the ability of simple process-based models to predict physical habitat features (e.g. bars), before investigating their ability to describe spatial and temporal trends of invertebrate community function, composition and response to physical perturbation. The simple nature of the approaches used in this study, which combine basic geomorphological models with traditional ecological metrics and functional traits, presents an opportunity to develop tools that allow river managers to base decisions on quantifiable measures of physical process instead of expert opinion. Overall, the results provided evidence of an implicit link between freshwater community composition, function, and the spatial variation in physical processes. Traditional and functional measures of community diversity showed a response to changing bed material calibre and stability across large spatial scales, consistent with other studies of habitat stability in rivers and other ecosystems. Despite this, there was limited evidence of temporal variability in communities due to riverbed disturbance, perhaps because water quality continued to suppress the physical habitat signal. Further work is required to isolate the effect of riverbed disturbance from other controlling mechanisms.
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Haan, Tara Jo. "Effects of Wildfire on Water Quality and Benthic Macroinvertebrate Communities of a Chihuahuan Desert Spring System." Miami University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=miami1345836591.
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