Dissertations / Theses on the topic 'Benthic fish'
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DeBlois, Elisabeth M. "Invertebrate predation on the benthic eggs of marine fish." Thesis, McGill University, 1992. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=39387.
Full textEnsign, William E. "Multiple-scale habitat models of benthic fish abundance in riffles." Diss., Virginia Tech, 1995. http://hdl.handle.net/10919/38204.
Full textPh. D.
Glaholt, Stephen P. Jr. "ECOSYSTEM RESPONSE TO BENTHIC DERIVED NUTRIENT SUBSIDIES FROM OMNIVOROUS FISH." Miami University / OhioLINK, 2003. http://rave.ohiolink.edu/etdc/view?acc_num=miami1057084183.
Full textRosenfeld, Jordan Stuart. "The effect of fish predation on benthic community structure in streams." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ34619.pdf.
Full textLiess, Antonia. "Nutrient Stoichiometry in Benthic Food Webs – Interactions Between Algae, Herbivores and Fish." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Universitetsbiblioteket [distributör], 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-6933.
Full textBryson, J. Glen. "Aspects of the ecology of the intertidal fish fauna of the Forth Estuary, Scotland." Thesis, Heriot-Watt University, 1997. http://hdl.handle.net/10399/664.
Full textSullivan, Joseph C. "Contemporary assessment of benthic macroinvertebrates and fish interactions in the Truckee River, NV." abstract and full text PDF (UNR users only), 2009. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1472981.
Full textMartínez, Gómez Concepción. "Sublethal effects of chemical pollution in benthic fish species from marine Spanish waters." Doctoral thesis, Universidad de Alicante, 2013. http://hdl.handle.net/10045/36264.
Full textFisco, Dana. "Reef Fish Spatial Distribution and Benthic Habitat Associations on the Southeast Florida Reef Tract." NSUWorks, 2016. http://nsuworks.nova.edu/occ_stuetd/408.
Full textJarving, Ohlsson Julius, and Linus Welander. "Hasslebäcken En studie av vattenkvalitet,vandringshinder och potentiellareproduktionsbiotoper för öring." Thesis, Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-32374.
Full textSchuchert, Pia Christiane. "Modelling Large Scale Coral Reef Fish and Benthic Community Structures in a Subsistence Fishing Environment." Thesis, University of Newcastle upon Tyne, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.519443.
Full textSchwinnen, Chad Robert. "Impacts of a Herbivorous Fish, Campostoma anomalum (central stoneroller), on Nitrogen Fixation by Benthic Algae." Wright State University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=wright1284993489.
Full textDorrien, Christian F. von. "Ökologie und Respiration ausgewählter arktischer Bodenfischarten = Ecology and respiration of selected Arctic benthic fish species /." Bremerhaven : Alfred-Wegener-Inst. für Polar- und Meeresforschung, 1993. http://www.gbv.de/dms/bs/toc/127460144.pdf.
Full textBowling, Anna Marie. "The impact of a benthic omnivore on the biomagnification of mercury in top-predator fish." Oxford, Ohio : Miami University, 2009. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=miami1250890267.
Full textWorischka, Susanne. "Selective predators in complex communities – mechanisms and consequences of benthic fish predation in small temperate streams." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-170972.
Full textCotterell, Stephen Paul. "Fish landings, discards and benthic material from demersal trawling in the western English Channel (ICES VIIe)." Thesis, University of Plymouth, 2006. http://hdl.handle.net/10026.1/2751.
Full textWasserman, Ryan J., Tim J. F. Vink, Tatenda Dalu, and Pierre William Froneman. "Fish predation regimes modify benthic diatom community structures: experimental evidence from an in situ mesocosm study." Ecological Society of Australia, 2015. http://hdl.handle.net/10962/68052.
Full textDiatoms are important primary producers in shallow water environments. Few studies have assessed the importance of biological interactions in structuring these communities. In the present study, benthic diatom community structure in relation to manipulated food webs was assessed using in situ mesocosms, whereby predator-free environments and environments comprising two different fish species were assessed. Zooplankton abundance, settled algal biomass and the diatom community were monitored over a 12‐day period across each of the three trophic scenarios. Differences among treatments over time were observed in zooplankton abundances, particularly copepods. Similarly, the benthic diatom community structure changed significantly over time across the three trophic treatments. However, no differences in total algal biomass were found among treatments. This was likely the result of non‐diatom phytoplankton contributions. We propose that the benthic diatom community structure within the mesocosms was influenced by trophic cascades and potentially through direct consumption by the fish. The study highlights that not only are organisms at the base of the food web affected by predators at the top of the food web, but that predator identity is potentially an important consideration for predator–prey interaction outcomes with consequences for multiple trophic levels.
Wahab, Md Abdul. "The ecology of benthic macro-invertebrates in earthen trout ponds at Howietoun, central Scotland." Thesis, University of Stirling, 1986. http://hdl.handle.net/1893/28840.
Full textLuecke, Chris M. "The effect of the introduction of cutthroat trout on the benthic community of Lake Lenore, Washington /." Thesis, Connect to this title online; UW restricted, 1986. http://hdl.handle.net/1773/5249.
Full textSantos, Rolando O. "Linkage Between Mangrove Fish Community and Nearshore Benthic Habitats in Biscayne Bay, Florida, USA: A Seascape Approach." NSUWorks, 2010. http://nsuworks.nova.edu/occ_stuetd/214.
Full textKim, Gene Wook. "Trophic transfer of energy and polychlorinated biphenyls by native and exotic fish in Lake Erie." Columbus, Ohio : Ohio State University, 2007. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1174664048.
Full textBailey, John L. "Evaluation of fish and benthic invertebrate bioassessments and the effects of placer mining on Yukon River Basin streams." Restricted access (UM), 2008. http://libraries.maine.edu/gateway/oroauth.asp?file=orono/etheses/37803141.pdf.
Full textIncludes Vita. Title from PDF title page (viewed on May 25, 2010) Available through UMI ProQuest Digital Dissertations. Includes bibliographical references (leaves 86-89). Also issued in print.
Siwabessy, Paulus Justiananda Wisatadjaja. "An investigation of the relationship between seabed type and benthic and bentho-pelagic biota using acoustic techniques." Thesis, Curtin University, 2001. http://hdl.handle.net/20.500.11937/1678.
Full textSiwabessy, Paulus Justiananda Wisatadjaja. "An investigation of the relationship between seabed type and benthic and bentho-pelagic biota using acoustic techniques." Curtin University of Technology, Department of Applied Physics, 2001. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=12197.
Full textThe approach used in this study is similar to,~ used in the commercial RoxAnn system. In grouping bottom types however, Multivariate analysis (Principal Component Analysis and Cluster Analysis) was adopted instead of the allocation system normally used in the RoxAnn system, called RoxAnn squares. In addition, the adopted approach allowed for quality control over acoustic data before further analysis was undertaken. As a working hypothesis, it was assumed that on average 0 and aE2 = 0 where E1 and E2 are the roughness and hardness indices, respectively, and RO is the depth. For roughness index (E1), this was achieved by introducing a constant angular integration interval to the tail of the first OM returns whereas for hardness index (E2), this was achieved by introducing a constant depth integration interval. Since three different frequencies, i.e. 12, 38 and kHz, were operated, Principal Component Analysis was used here to reduce the dimensionality of roughness and hardness indices, formed from the three operated qu frequencies separately. The k-means technique was applied to the first principal component of roughness index and the first principal comp component of hardness index to produce separable seabed types. This produced four separable seabed types, namely soft-smooth, soft-rough, hard-smooth and hard-rough seabeds.
Principal Component Analysis was also used to reduce the dimensionality of the area backscattering coefficient sA, a relative measure of biomass of benthic mobile biota. The bottom classification results reported here appear to be robust in that, where independent ground truthing was available, acoustic classification was generally congruent with ground truth results. When investigating the relationship between derived bottom type and acoustically assessed total biomass of benthic mobile biota, no trend linking the two parameters, however, appears. Nevertheless, using the hierarchical agglomerative technique applied to a set of variables containing average first principal component of the area backscattering coefficient sA, the average first principal component of roughness and hardness indices, the centroids of first principal component of roughness and hardness indices associated with the four seabed types and species composition of fish group of the common species in trawl stations available, two main groups of quasi acoustic population are observed in the North West Shelf (NWS) study area and three groups are observed in the South East Fisheries (SEF) study area. The two main groups of quasi acoustic population in the NWS study area and the three main groups of quasi acoustic population in the study area are associated with the derived seabed types and fish groups of the common species.
Molin, Johan. "Predation på evertebrater under tidig vår i sjön Tåkern." Thesis, Linköpings universitet, Biologi, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-79044.
Full textYang, Yao, and 楊瑤. "The ecology of a herbivorous fish (Pseudogastromyzon myersi: balitoridae) and its influence on benthic algal dynamics in four HongKong streams." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2008. http://hub.hku.hk/bib/B41508646.
Full textGonçalves, Cátia Vanessa Caetano. "Can the complex mixture of sediment contaminants cause endocrine disruption on a benthic fish? A case study with Solea senegalensis." Master's thesis, Faculdade de Ciências e Tecnologia, 2013. http://hdl.handle.net/10362/10811.
Full textProjecto HERA (PTDC/SAU-ESA/100107/2008)
Kirk, Andrew J. "Seasonal Variation of Fish and Macroinvertebrate Biomass Spectra in Southern West Virginia Streams." VCU Scholars Compass, 2016. http://scholarscompass.vcu.edu/etd/4228.
Full textAigbavbiere, Ernest. "How does predation from fish influence the benthic invertebrates’ species composition in the Phragmites australis and Chara vegetation of Lake Takern?" Thesis, Linköpings universitet, Ekologi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-72643.
Full textMSc Ecology and Environmental Science
Yang, Yao. "The ecology of a herbivorous fish (Pseudogastromyzon myersi: balitoridae) and its influence on benthic algal dynamics in four Hong Kong streams." Click to view the E-thesis via HKUTO, 2008. http://sunzi.lib.hku.hk/hkuto/record/B41508646.
Full textIlich, Alexander Ross. "Integrating Towed Underwater Video with Multibeam Acoustics for Mapping Benthic Habitat and Assessing Reef Fish Communities on the West Florida Shelf." Scholar Commons, 2018. https://scholarcommons.usf.edu/etd/7525.
Full textKim, Gene W. "Trophic transfer of energy and polychlorinated biphenyls by native and exotic fish in Lake Erie." The Ohio State University, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=osu1174664048.
Full textAndré, Emidio Raul. "Benthic nutrient cycling, the role of fish in nitrogen and phosphorus regeneration in the rocky littoral zone of Lake Malawi/Nyasa/Niassa, Africa." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0023/MQ51625.pdf.
Full textAndr??, Emidio Raul. "Benthic nutrient cycling, the role of fish in nitrogen and phosphorus regeneration in the rocky littoral zone of Lake Malawi/Nyasa/Niassa, Africa." Thesis, National Library of Canada = Biblioth??que nationale du Canada, 2000. http://hdl.handle.net/10012/49.
Full textDunnigan, Shannon K. "Habitat Value of Restored Intertidal Shoreline for Fish and Macrobenthic Communities in Northeast Florida." UNF Digital Commons, 2015. http://digitalcommons.unf.edu/etd/597.
Full textWorischka, Susanne [Verfasser], Thomas [Akademischer Betreuer] Berendonk, Markus [Akademischer Betreuer] Weitere, and Jürgen [Akademischer Betreuer] Geist. "Selective predators in complex communities – mechanisms and consequences of benthic fish predation in small temperate streams / Susanne Worischka. Gutachter: Thomas Berendonk ; Markus Weitere ; Jürgen Geist. Betreuer: Thomas Berendonk." Dresden : Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2015. http://d-nb.info/1073207021/34.
Full textKapusinski, Douglas John. "Factors Affecting Invertebrate and Fish Communities in Coastal Wetlands of the Great Lakes." Kent State University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=kent1353202400.
Full textPasquini, Giulia. "Assessment of marine litter in the Western Adriatic Sea and its impact on marine biota." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amslaurea.unibo.it/10043/.
Full textWhitney, James E. "Spatiotemporal response of aquatic native and nonnative taxa to wildfire disturbance in a desert stream network." Diss., Kansas State University, 2014. http://hdl.handle.net/2097/18217.
Full textDepartment of Biology
Keith B. Gido
Many native freshwater animals are imperiled as a result of habitat alteration, species introductions and climate-moderated changes in disturbance regimes. Native conservation and nonnative species management could benefit from greater understanding of critical factors promoting or inhibiting native and nonnative success in the absence of human-caused ecosystem change. The objectives of this dissertation were to (1) explain spatiotemporal patterns of native and nonnative success, (2) describe native and nonnative response to uncharacteristic wildfire disturbance, and (3) test the hypothesis that wildfire disturbance has differential effects on native and nonnative species. This research was conducted across six sites in three reaches (tributary, canyon, and valley) of the unfragmented and largely-unmodified upper Gila River Basin of southwestern New Mexico. Secondary production was measured to quantify success of native and nonnative fishes prior to wildfires during 2008-2011. Native fish production was greater than nonnatives across a range of environmental conditions, although nonnative fish, tadpole, and crayfish production could approach or exceed that of native macroinvertebrates and fishes in canyon habitats, a warmwater tributary, or in valley sites, respectively. The second objective was accomplished by measuring biomass changes of a warmwater native and nonnative community during 2010-2013 before and after consecutive, uncharacteristic wildfires. Several native insect and fish taxa decreased after both wildfires, whereas nonnative decreases were most pronounced for salmonids and more limited for other taxa. Finally, effects of uncharacteristic wildfires followed by extreme flooding on metapopulations of native and nonnative fishes were contrasted during 2008-2013. Wildfire and flood disturbances increased extinction probabilities of all native fishes while leaving many nonnative fishes unaffected. These findings revealed a swinging pendulum of native and nonnative success, wherein wildfire disturbance resulted in a pendulum swing in favor of nonnatives. Ensuring the pendulum swings back in favor of natives will be facilitated by management activities that decrease wildfire size and intensity and maintain inherent ecosystem resilience.
Ashley, Matthew. "The implications of co-locating marine protected areas around offshore wind farms." Thesis, University of Plymouth, 2014. http://hdl.handle.net/10026.1/3202.
Full textGrant, Bridie. "Development of broodstock management and husbandry tools for improved hatchery performance of ballan wrasse (Labrus bergylta)." Thesis, University of Stirling, 2016. http://hdl.handle.net/1893/24416.
Full textKilgour, Bruce William. "Fish-benthos correlations and effects on benthos that reflect significant effects on fish communities in southern Ontario streams." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq22213.pdf.
Full textRosa, Marcos Rogerio. "Reef communities of the Saint Peter and Saint Paul\'s Archipelago across an euphotic-mesophotic depth gradient (0-90 m)." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/21/21134/tde-10042015-135758/.
Full textO tema central desta tese é estudar a ecologia de comunidades recifais ao longo do gradiente de profundidade no Arquipélago São Pedro e São Paulo (ASPSP), com ênfase nos Ecossistemas Recifais Mesofóticos (ERMs). As amostragens foram realizadas da superfície até a zona mesofótica (0 a 90 m de profundidade), utilizando SCUBA e Veículos Submersíveis de Operação Remota (VSORs). Esta tese é composta por quatro capítulos. No Capítulo 1 foi realizado uma avaliação quantitativa das comunidades de peixes, as quais formaram três comunidades distintas associadas aos diferentes estratos de profundidade e ao uso de diferentes hábitats de acordo com mudanças ontogenéticas (tamanho do corpo). Corais-negros e profundidade foram os fatores mais importantes na estruturação das comunidades de peixes, com uso intenso dos corais-negros por peixes na zona mesofótica. O Capítulo 2 apresenta a primeira avaliação qualitativa das comunidades bentônicas do ASPSP, além de uma avaliação da influência de variáveis bióticas e abióticas na estruturação das comunidades. Foram registrados 77 táxons bentônicos pertencentes a seis grupos. Macroalgas foi o grupo mais rico (41 táxons), com 17 novos registros para o ASPSP. Algas formadoras de tufos (turf) constituíram o grupo mais abundante em ambos os ambientes, eufótico e mesofótico. Foram observadas duas comunidades distintas: uma superficial composta principalmente pelo zoantídeo Palythoa caribaeorum, a pela alga Caulerpa racemosa carnuda, algas calcárias incrustantes (CCA) e Bryopsis spp, e outra mais profunda dominada por CCA, briozoários e corais escleractíneos. As variáveis abióticas, particularmente profundidade e luz, foram mais importantes na estrutura da comunidade bentônica. O Capítulo 3 traz informações sobre a abundância, distribuição, tamanho e vitalidade de corais-negros. Duas espécies de corais-negros, Tanacetipathes hirta (Gray, 1857) e T. thamnea (Warner, 1981), foram identificadas. Epibiose por zoantídeos e estrangulamento por monofilamentos afetaram negativamente as colônias de coral negro, uma delas monitorada durante dez anos. Esta última apresentou uma diminuição da vitalidade devido principalmente à presença de algas e estrangulamento por monofilamento. Corais-negros formam um grupo-chave na zona mesofótica do ASPSP, sendo intensamente utilizados como hábitat por diversos peixes recifais, principalmente espécies endêmicas (e.g., o peixe-borboleta Prognathodes obliquus). O Capítulo 4 aborda a ecologia do principal predador de invertebrados bentônicos na zona mesofótica do ASPSP, o verme-de-fogo Hermodice carunculata, descrevendo sua abundância e distribuição batimétrica e discutindo seu potencial em impactar as comunidades bentônicas, especialmente os corais escleractínios e os corais-negros na zona mesofótica do ASPSP. Observou-se um total de 278 indivíduos, com diferença significativa na abundância entre as zonas eufótica e mesofótica. Foi encontrada uma associação direta entre H. carunculata e 1) corais-negros (Tanacetipathes spp), 2) o coral escleractíneo Madracis decactis e 3) profundidade. Sugere-se aqui que os ecossistemas mesofóticos são essenciais para a estabilidade para as comunidades recifais eufóticas do ASPSP, tornando urgente a necessidade de novos estudos, principalmente com foco no potencial impacto da pesca e mudanças climáticas.
Fielding, Nicola Jane. "Fish and benthos communities in regenerated dock systems on Merseyside." Thesis, University of Liverpool, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.482788.
Full textCuvillier, Alexis. "Dynamique et fonctionnement des herbiers marins dans un complexe récifal anthropisé (île de la Réunion, océan Indien)." Thesis, La Réunion, 2016. http://www.theses.fr/2016LARE0037/document.
Full textLocated at the benthos-pelagos interface, seagrass beds have many ecosystemic roles such as coastal protection or biodiversity. Historically, scientists and decision-makers at Reunion Island have been focusing on reef ecosystems. However, for several decades, monospecific (Syringodium isoetifolium) seagrass beds have been observed (3 hectares – 2013) within Ermitage / La Saline reef (West coast). The main objective of this study was to give the first data on seagrass ecology at Reunion Island. Therefore, a multi-disciplinary study was developed. First, seascape ecology of seagrasses is analyzed at decadal (since 1950) and seasonal scales (2013-2015). Physical settings (swell) and eutrophication were driving factors on the spatial dynamics of seagrass beds. Second, seagrass community metabolism and response to nutrient loads (nitrate and phosphate) show variations in metabolic budget (autotrophy to heterotrophy) and make seagrass beds a nutrient sink following the environmental conditions. Third, stable isotope analysis (δ13C and δ15N) identified sources of particulate matter entering the ecosystem and fueling food webs. The trophic roles of seagrass beds are assessed for echinoderm and herbivorous fish communities. This study highlighted a trophic link between seagrass and Holothuria leucospilota, and proved some species to be heavily dependent on seagrass ecosystem (Leptoscarus vaigiensis, Siganus sutor). Finally, interviews showed a lack of knowledge about this ecosystem despite crucial economic and ecologic roles. Considering their major functions, seagrass beds have to be considered in future management of the coastal marine systems at Reunion Island
Sanz, Lázaro Carlos. "Consecuencias ecológicas del enriquecimiento por materia orgánica procedente de la acuicultura y de vertidos de petróleo en ecosistemas costeros." Doctoral thesis, Universidad de Murcia, 2009. http://hdl.handle.net/10803/10776.
Full textThe aim of this thesis is to study the effect of organic matter enrichment produced by marinefinfish farming and oil spills on the marine environment. This work is focused on elucidating theecological consequences of the impact generated by this type of pollution, and on designingtoxictity tests to evaluate pollution for southern European coasts. Specifically, related with aquaculture impact, it studies benthic recovery during open sea fish farming abatement, the role of predation in the benthic system and links horizontal and vertical waste dispersion with benthic impact.
Gaspar, Margarida Veríssimo. "Implicações da sazonalidade na avaliação do estado ecológico em rios de tipo mediterrâneo: será a amostragem adequada?" Master's thesis, Universidade de Évora, 2013. http://hdl.handle.net/10174/16095.
Full textMarzin, Anahita. "Indicateurs biologiques de la qualité écologique des cours d’eau : variabilités et incertitudes associées." Thesis, Paris, AgroParisTech, 2013. http://www.theses.fr/2013AGPT0002/document.
Full textSensitive biological measures of ecosystem quality are needed to assess, maintain or restore the ecological conditions of rivers. Since our understanding of these complex systems is imperfect, river management requires recognizing variability and uncertainty of bio-assessment for decision-making. Based on the analysis of national data sets (~ 1654 sites), the main goals of this work were (1) to test some of the assumptions that shape bio-indicators and (2) address the temporal variability and the uncertainty associated to prediction of reference conditions.(1) This thesis highlights (i) the predominant role of physiographic factors in shaping biological communities in comparison to human pressures (defined at catchment, riparian corridor and reach scales), (ii) the differences in the responses of biological indicators to the different types of human pressures (water quality, hydrological, morphological degradations) and (iii) more generally, the greatest biological impacts of water quality alterations and impoundments. (2) A Bayesian method was developed to estimate the uncertainty associated with reference condition predictions of a fish-based bio-indicator (IPR+). IPR+ predictive uncertainty was site-dependent but showed no clear trend related to the environmental gradient. By comparison, IPR+ temporal variability was lower and sensitive to an increase of human pressure intensity. This work confirmed the advantages of multi-metric indexes based on functional metrics in comparison to compositional metrics. The different sensitivities of macrophytes, fish, diatoms and macroinvertebrates to human pressures emphasize their complementarity in assessing river ecosystems. Nevertheless, future research is needed to better understand the effects of interactions between pressures and between pressures and the environment
Langhamer, Olivia. "Wave energy conversion and the marine environment : Colonization patterns and habitat dynamics." Doctoral thesis, Uppsala universitet, Elektricitetslära, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-107193.
Full textTableau, Adrien. "Interactions trophiques au sein des communautés bentho-demersales : Influence de la disponibilité alimentaire sur la capacité d’accueil des nourriceries côtières de juvéniles de poissons." Thesis, Rennes, Agrocampus Ouest, 2015. http://www.theses.fr/2015NSARH095/document.
Full textSoft sediment coastal habitats are essential in the life cycle of numerous fishes. These habitats are spatially-limited but very productive, and play a key role of nursery for the juveniles of benthic and demersal fishes. High abundance of prey seems to be one of the main reasons of the presence of juvenile fish within these habitats. Although widely studied, the limiting aspect of the feeding factor is still debated in the scientific community. One of the main reasons is that studying coastalhabitats is complex because numerous factors influence the development of the first life stages of fish. From the study case of the Bay of Vilaine, one of the most productive nurseries of the Bay of Biscay, research conducted in this thesis aims to define the role of the feeding factor in the organisation of the nursery and in its capacity to support the development of juvenile fish. The common thread of this thesis is thus to determine if the feeding factor limits the juvenile fish production. The results show a strong exploitation of the food production by the juvenile fish community and a spatial match between the densities of juvenile fish and their prey. The consistency of these results tends to support that the hypothesis that the carrying capacity of the Bay of Vilaine is reached, and that the feeding factor is limiting. The consequences of this regulation process on the dynamics of nursery-dependent fish populations are discussed