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1
Coman, Francis Edmund, i n/a. "The Role of Epibenthic and Planktonic Fauna in Subtropical Prawn Grow Out Ponds". Griffith University. School of Environmental and Applied Science, 2003. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20030926.091736.
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The assemblage composition, biomass and dynamics of zooplankton and epibenthos were examined in a commercial prawn pond in southeast Queensland over two seasons. Physico-chemical characteristics of the pond water were measured concurrently. Numbers and biomass of zooplankton in the surface tows (140 micrometre mesh) varied from 8 ind. L-1 (44 micrograms L-1) to 112 ind. L-1 (324 micrograms L-1) in the first season, with peaks in biomass corresponding to peaks in numbers. In the second season the zooplankton numbers varied from 12 to 590 ind. L-1, but peaks in numbers did not correspond with peaks in biomass, which varied from 28 to 465 micrograms L-1. This was due to differences in the size of the dominant taxa across the season. Although this occurred in both seasons, the effect on biomass was more pronounced in the second season. In both seasons, immediately after the ponds were stocked with prawn postlarvae there was a rapid decline in zooplankton numbers, particularly of the dominant larger copepods. This was probably due to predation by the postlarvae. Subsequent peaks in zooplankton numbers were principally due to barnacle nauplii. The largest peaks in zooplankton numbers occurred before stocking in the first season, but the largest peaks were in the middle of the second season. While changes in abundance and biomass of the zooplankton assemblage were not correlated with physico-chemical characteristics in the first season, there were correlations between zooplankton numbers and temperature, dissolved oxygen, pH and secchi disk readings in the second season. No correlations were found with zooplankton biomass and physico-chemical characteristics in the second season. The correlations in the second season were mainly due to the high prevalence of barnacle nauplii through the middle part of the season, and may reflect suitable conditions for barnacle reproduction. Epibenthic faunal abundance in the beam trawls (1 mm mesh) peaked at 14 ind. m-2 and 7 ind. m-2 in the first and second seasons respectively and the biomasses at 0.8 g m-2 and 0.7 g m-2. Peaks in abundance of epibenthos did not correspond to peaks in biomass. This was due to large differences in the size of the taxa across the seasons. Sergestids (Acetes sibogae) and amphipods were the most abundant taxa in beam trawl samples. Amphipods were only abundant in the first season, with their numbers increasing towards the end of the grow out period. Acetes were abundant in both seasons, but were dominant in the second season. Correlations between physico-chemical parameters and epibenthos numbers were found to be strongly influenced by the dominant taxa in each season. In the first season, negative correlations were found between epibenthos abundance and pH and temperature. These relationships may reflect an effect on the growth of macroalgae in the pond, with which the amphipods were strongly associated, rather than a direct effect on the epibenthos. In the second season, a positive correlation existed between temperature and epibenthos abundance, however this was strongly influenced by the very high abundance of Acetes in the last sampling period. No correlations were found between epibenthic fauna biomass and physico-chemical parameters. Abundances of epibenthic fauna were not related to zooplankton densities indicating this source of food was not likely to be a limiting factor. Neither the pond water exchange regime nor moon phase could explain changes observed in abundances of zooplankton or epibenthos assemblages in the first season, however the sampling regime was not designed to specifically investigate these effects. In the second season water exchanges were sampled more rigorously. The density of zooplankton in the outlet water was from 2 to 59% of the density of zooplankton in the pond, and the zooplankton density of the inlet water was from 9 to 50% of the outlet water. The number of zooplankton recruited into the pond from the inlet water, after the prawns were stocked, was negligible and contributed little to changes observed in zooplankton assemblages. Reproduction of barnacles within the pond appeared to play the most important role in changes in the assemblage. Water exchange did, however, appear to play a greater role in the changes observed in epibenthic fauna assemblages. In the last season of sampling the feeding of the dominant epibenthic species, Acetes sibogae, was examined using a combination of gut content and stable isotope analysis. Acetes gained little nutrition directly from the pelleted feed, probably relying primarily on zooplankton as their direct food source. Other dietary items such as macroalgae also played a role in the nutrition of the Acetes. If Acetes numbers were high at the beginning of a season they may compete with the newly stocked prawns for the zooplankton resource. However, they will not compete with the prawns later in the season when the prawns are gaining most of their nutrition from the pelleted feed. Overall it appears that zooplankton are important to the nutrition of the prawns at the beginning of the season when the assemblage is usually dominated by copepods. Later in the season the assemblage is dominated by barnacle nauplii which are recruited from within the pond. The establishment of an abundant assemblage of suitable zooplankton species before stocking prawn postlarvae would appear to be beneficial, if not essential. The assemblage of epibenthic fauna changes throughout the season as new recruits are brought in from outside the pond. Epibenthic faunal assemblages in ponds from southeast Queensland are dominated by Acetes which are not likely to adversely affect the production of prawns unless they are particularly abundant early in the grow out season when the prawns would be utilising the same food resources as Acetes.
2
Coman, Francis Edmund. "The Role of Epibenthic and Planktonic Fauna in Subtropical Prawn Grow Out Ponds". Thesis, Griffith University, 2003. http://hdl.handle.net/10072/367812.
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The assemblage composition, biomass and dynamics of zooplankton and epibenthos were examined in a commercial prawn pond in southeast Queensland over two seasons. Physico-chemical characteristics of the pond water were measured concurrently. Numbers and biomass of zooplankton in the surface tows (140 micrometre mesh) varied from 8 ind. L-1 (44 micrograms L-1) to 112 ind. L-1 (324 micrograms L-1) in the first season, with peaks in biomass corresponding to peaks in numbers. In the second season the zooplankton numbers varied from 12 to 590 ind. L-1, but peaks in numbers did not correspond with peaks in biomass, which varied from 28 to 465 micrograms L-1. This was due to differences in the size of the dominant taxa across the season. Although this occurred in both seasons, the effect on biomass was more pronounced in the second season. In both seasons, immediately after the ponds were stocked with prawn postlarvae there was a rapid decline in zooplankton numbers, particularly of the dominant larger copepods. This was probably due to predation by the postlarvae. Subsequent peaks in zooplankton numbers were principally due to barnacle nauplii. The largest peaks in zooplankton numbers occurred before stocking in the first season, but the largest peaks were in the middle of the second season. While changes in abundance and biomass of the zooplankton assemblage were not correlated with physico-chemical characteristics in the first season, there were correlations between zooplankton numbers and temperature, dissolved oxygen, pH and secchi disk readings in the second season. No correlations were found with zooplankton biomass and physico-chemical characteristics in the second season. The correlations in the second season were mainly due to the high prevalence of barnacle nauplii through the middle part of the season, and may reflect suitable conditions for barnacle reproduction. Epibenthic faunal abundance in the beam trawls (1 mm mesh) peaked at 14 ind. m-2 and 7 ind. m-2 in the first and second seasons respectively and the biomasses at 0.8 g m-2 and 0.7 g m-2. Peaks in abundance of epibenthos did not correspond to peaks in biomass. This was due to large differences in the size of the taxa across the seasons. Sergestids (Acetes sibogae) and amphipods were the most abundant taxa in beam trawl samples. Amphipods were only abundant in the first season, with their numbers increasing towards the end of the grow out period. Acetes were abundant in both seasons, but were dominant in the second season. Correlations between physico-chemical parameters and epibenthos numbers were found to be strongly influenced by the dominant taxa in each season. In the first season, negative correlations were found between epibenthos abundance and pH and temperature. These relationships may reflect an effect on the growth of macroalgae in the pond, with which the amphipods were strongly associated, rather than a direct effect on the epibenthos. In the second season, a positive correlation existed between temperature and epibenthos abundance, however this was strongly influenced by the very high abundance of Acetes in the last sampling period. No correlations were found between epibenthic fauna biomass and physico-chemical parameters. Abundances of epibenthic fauna were not related to zooplankton densities indicating this source of food was not likely to be a limiting factor. Neither the pond water exchange regime nor moon phase could explain changes observed in abundances of zooplankton or epibenthos assemblages in the first season, however the sampling regime was not designed to specifically investigate these effects. In the second season water exchanges were sampled more rigorously. The density of zooplankton in the outlet water was from 2 to 59% of the density of zooplankton in the pond, and the zooplankton density of the inlet water was from 9 to 50% of the outlet water. The number of zooplankton recruited into the pond from the inlet water, after the prawns were stocked, was negligible and contributed little to changes observed in zooplankton assemblages. Reproduction of barnacles within the pond appeared to play the most important role in changes in the assemblage. Water exchange did, however, appear to play a greater role in the changes observed in epibenthic fauna assemblages. In the last season of sampling the feeding of the dominant epibenthic species, Acetes sibogae, was examined using a combination of gut content and stable isotope analysis. Acetes gained little nutrition directly from the pelleted feed, probably relying primarily on zooplankton as their direct food source. Other dietary items such as macroalgae also played a role in the nutrition of the Acetes. If Acetes numbers were high at the beginning of a season they may compete with the newly stocked prawns for the zooplankton resource. However, they will not compete with the prawns later in the season when the prawns are gaining most of their nutrition from the pelleted feed. Overall it appears that zooplankton are important to the nutrition of the prawns at the beginning of the season when the assemblage is usually dominated by copepods. Later in the season the assemblage is dominated by barnacle nauplii which are recruited from within the pond. The establishment of an abundant assemblage of suitable zooplankton species before stocking prawn postlarvae would appear to be beneficial, if not essential. The assemblage of epibenthic fauna changes throughout the season as new recruits are brought in from outside the pond. Epibenthic faunal assemblages in ponds from southeast Queensland are dominated by Acetes which are not likely to adversely affect the production of prawns unless they are particularly abundant early in the grow out season when the prawns would be utilising the same food resources as Acetes.Thesis (Masters)
Master of Philosophy (MPhil)
School of Environmental and Applied Science
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3
Starmans, Andreas. "Vergleichende Untersuchungen zur Ökologie und Biodiversität des Mega-Epibenthos der Arktis und Antarktis = Comparative studies on the ecology and biodiversity of the Arctic and Antarctic Mega-Epibenthos /". Bremerhaven : Alfred-Wegener-Inst. für Polar- und Meeresforschung, 1997. http://www.gbv.de/dms/bs/toc/238435679.pdf.
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4
Polte, Patrick. "Ecological functions of intertidal seagrass beds for fishes and mobile epibenthos in the northern Wadden Sea". [S.l.] : [s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=979700191.
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5
Dupont, Jennifer Maria. "Ecological dynamics of livebottom ledges and artificial reefs on the inner central West Florida Shelf". [Tampa, Fla] : University of South Florida, 2009. http://purl.fcla.edu/usf/dc/et/SFE0002841.
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6
Rubin, J. A. "Spatial and temporal interactions in sublittoral epibenthic communities". Thesis, University of Reading, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.354095.
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7
Boström, Minna. "Epibenthic predators and their prey : interactions in a coastal food web /". Åbo : Department of biology/environmental and marine biology, Åbo akademi university, 2002. http://catalogue.bnf.fr/ark:/12148/cb39933839r.
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8
Netchy, Kristin. "Epibenthic Mobile Invertebrates along the Florida Reef Tract: Diversity and Community Structure". Scholar Commons, 2014. https://scholarcommons.usf.edu/etd/5085.
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Benthic mobile invertebrates are important components of coral-reef diversity and community structure, though, in most cases, their ecological contributions are poorly known. Baseline information on their diversity, prevalence, assemblages, and ecological roles is needed to aid in the conservation of coral-reef habitats. The objectives of this study are to 1) describe diversity and assemblages of epibenthic, mobile invertebrates in shallow water coral-reef communities in Florida, 2) evaluate their ecological roles by reviewing published literature on diet, and 3) measure the degree of linear dependence between mobile invertebrates and scleractinian corals. Underwater surveys were conducted in the summer of 2013 at 40 sites distributed along the Florida Reef Tract from Broward County to the Dry Tortugas. The presence/absence of all mobile, epibenthic invertebrate fauna observed were recorded and identified to the lowest level possible. The survey data include 618 records of 116 unique taxa, 83 species, 61 genera, 46 families, 19 orders, seven classes, and four phyla of mobile invertebrates, comprising herbivores, detritivores, carnivores, omnivores, and suspension feeders. These taxa represent 22% of the comparable taxa in a historical dataset that spans 60 years, plus an additional 18 taxa. The survey data also show that the percent composition of major phyla is similar to the historical dataset, despite taxonomic bias evident in the historical dataset. During the survey, novel unique taxa were encountered frequently, but were seldom recurrent, which highlights their cryptic nature. While regional patterns were not identified in the study, assemblages of dominant taxa were characteristic of reef type: echinoderms were the most diverse on patch reefs and southeast Florida reef complexes, mollusks were most diverse on shallow bank reefs, and arthropods were diverse on deep bank reefs, Southeast Florida reef complexes, and shallow bank reefs. Herbivorous mobile invertebrate diversity was negatively correlated with scleractinian coral diversity, underlining competition between corals and macroalgae, and association of herbivores with macroalgae. All of these results suggest that reef types are distinct, but interrelated communities of fauna having specific habitat requirements and important roles. This study also reinforces the challenges in assessing the diverse and often cryptic mobile invertebrate fauna and emphasizes the need for further research and monitoring to detect changes in their communities for the conservation of Florida reef systems.
9
Hawkins, Susan Terry. "The epibenthic colonization of artificial subtidal habitats at the Cape d'Aguilar Marine Reserve, Hong Kong". Thesis, Hong Kong : University of Hong Kong, 1998. http://sunzi.lib.hku.hk/hkuto/record.jsp?B20357801.
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10
Seitz, Rochelle D. "The role of epibenthic predators in structuring marine soft-bottom communities along an estuarine gradient". W&M ScholarWorks, 1996. https://scholarworks.wm.edu/etd/1539616850.
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A unifying theory of community regulation in soft-bottom systems remains elusive, despite extensive field studies on factors controlling community structure. Here, I have (1) reviewed models of community regulation, (2) examined the role of predation in controlling benthic diversity along a salinity gradient, (3) examined effects of predation upon an abundant bivalve, Macoma balthica, and (4) revised a model of community regulation in an estuarine soft-bottom system. The Menge and Sutherland (MS) "consumer stress model" posits that consumers feed ineffectively in harsh environments, and the importance of physical disturbance, competition and predation varies with recruitment, environmental conditions, and trophic position. In this model, competition for resources depends directly upon the level of recruitment. I have revised the model to fit soft-bottom systems by changing the recruitment axis to a "recruitment: resource ratio." Hence, the impact of a given level of recruitment depends upon resource availability. According to the MS model, predation is most important in determining community structure when environmental conditions are not severe. I investigated the applicability of the MS model in a soft-bottom estuarine community. I quantified predator abundance, prey abundance and diversity, and the differential effect of predation on species diversity and survival of an abundant prey species, Macoma balthica, along an estuarine gradient in two tributaries of Chesapeake Bay. Benthic diversity was lower in upriver high-stress habitats than downriver low-stress habitats, in agreement with predictions of the MS model. However, the following findings are inconsistent with model predictions: (1) predator abundance was greater upriver, (2) predation intensity and its impact on benthic diversity were greater upriver, and (3) predation-induced mortality of transplanted Macoma balthica clams, and natural mortality of clams were higher upriver. An alternative community regulation model applies to this system because higher predator abundance and predation intensity in higher environmental stress is contrary to the MS model predictions. Predators aggregated upriver where carbon production was increased, and prey were abundant. Hence, a more suitable model for this soft-bottom system is one that incorporates the effects of production and predation along with recruitment, competition and environmental stress.
11
Ferro, Francesca. "Ruolo della gorgonia Paramuricea clavata (Risso 1826) nei popolamenti epibentonici coralligeni dell'Isola d'Elba". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amslaurea.unibo.it/10054/.
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The red gorgonian Paramuricea clavata is considered a key species in Mediterranean coralligenous habitats and, when present at high density, its colonies may develop “gorgonian forests”, which are three-dimensional structures that increase habitat complexity. Mediterranean coralligenous habitats support high biodiversity but the structure and heterogeneity of communities can be strongly modified by several kinds of human-derived impacts. The global environmental change and human activity could threaten the coralligenous habitats and during the last few decades, Mediterranean suspension feeders have been involved in mass mortality events, in which P. clavata was one of the most affected. Without the complex three-dimensional structures formed by P. clavata, many benthic species may have not adequate sheltering and feeding opportunities. The aim of the present study was to investigate the ecological role of Paramuricea clavata in coralligenous habitats by comparing epibenthic assemblages established inside and outside gorgonian forests. This study was carried out in four sites randomly chosen, along the south-east coast of Elba island (north-western Mediterranean). The structure of the epibenthic assemblages were significantly different between area with and without gorgonians. Main differences concern very important taxa in the coralligenous bioconstruction processes like the encrusting red algae, Peyssonnelia spp. and Halimeda tuna, which were more abundant in presence of gorgonians. On the contrary, algal turf, mucilaginous algae and the invasive seaweed Caulerpa cylindracea were more abundant in areas without P. clavata. The presence of gorgonians may have a positive effect also on species diversity. The results of this study highlight the ecological role of P. clavata in the coralligenous habitats.
12
Bellon, Marianna. "Variabilità spaziale e temporale dei popolamenti epibentonici sommersi delle Isole Tremiti". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017.
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The present study aimed at estimating the spatial distribution and temporal variation of epibenthic assemblages Tremiti Islands (42° 07’ North 15° 30’ East) by photographic sampling from 2012 to 2015 at 2 randomly selected areas within 2 sites and at 2 depths (6 and 18 m depth).
Overall, 65 taxa were identified. The dominant taxa were Peyssonnelia spp., Dyctiotales, Codium bursa, Codium effusum, Halimeda tuna, Pseudochlorodesmis furcellata, algal turf, Ircinia spp., Chondrosia reniformis and Rocellaria dubia. Composition of the assemblages varied through years and among sites. As a general pattern, shallower assemblages were more variable in time. Although the study was limited to the euphotic zone, these observations support the general tendency, already described in deeper investigations, toward greater stability and less dynamism with increasing depth.
Result indicated that patterns of distribution and abundance of organisms differed between the two depths for all the years. The assemblages showed a high diversity, especially in relation to the smaller spatial scale examined. Sites clearly differed in the abundance of the main taxa and some taxa showed site-specific trend.
Coralligenous outcrops rank among the most important ecosystems in the Mediterranean Sea, primarily because of their biodiversity. Information on the spatial and temporal variability of the composition and structure of coralligenous assemblages is essential for the management and conservation of these unique biogenic habitat.
13
Fava, Federica <1978>. "Spatial and temporal variability and ecological processes in the epibenthic assemblages of the northern Adriatic Sea". Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2011. http://amsdottorato.unibo.it/3677/.
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Several coralligenous reefs occur in the soft bottoms of the northern Adriatic continental shelf. Mediterranean coralligenous habitats are characterised by high species diversity and are intrinsically valuable for their biological diversity and for the ecological processes they support. The conservation and management of these habitats require quantifying spatial and temporal variability of their benthic assemblages. This PhD thesis aims to give a relevant contribution to the knowledge of the structure and dynamics of the epibenthic assemblages on the coralligenous subtidal reefs occurring in the northern Adriatic Sea.
The epibenthic assemblages showed a spatial variation larger compared to temporal changes, with a temporal persistence of reef-forming organisms. Assemblages spatial heterogeneity has been related to morphological features and geographical location of the reefs, together with variation in the hydrological conditions.
Manipulative experiments help to understand the ecological processes structuring the benthic assemblages and maintaining their diversity. In this regards a short and long term experiment on colonization patterns of artificial substrata over a 3-year period has been performed in three reefs, corresponding to the three main types of assemblages detected in the previous study. The first colonisers, largely depending by the different larval supply, played a key role in determining the heterogeneity of the assemblages in the early stage of colonisation. Lateral invasion, from the surrounding assemblages, was the driver in structuring the mature assemblages. These complex colonisation dynamics explained the high heterogeneity of the assemblages dwelling on the northern Adriatic biogenic reefs.
The buildup of these coralligenous reefs mainly depends by the bioconstruction-erosion processes that has been analysed through a field experiment. Bioconstruction, largely due to serpulid polychaetes, prevailed on erosion processes and occurred at similar rates in all sites. Similarly, the total energy contents in the benthic communities do not differ among sites, despite being provided by different species. Therefore, we can hypothesise that both bioconstruction processes and energetic storage may be limited by the availability of resources. Finally the major contribution of the zoobenthos compared to the phytobenthos to the total energetic content of assemblages suggests that the energy flow in these benthic habitats is primarily supported by planktonic food web trough the filter feeding invertebrates.
14
Linse, Katrin. "Die Verbreitung epibenthischer Mollusken im chilenischen Beagle-Kanal = Distribution of epibenthic mollusca from the Chilean Beagle Channel /". Bremerhaven : Alfred-Wegener-Institut für Polar- und Meeresforschung, 1997. http://www.gbv.de/dms/bs/toc/226600386.pdf.
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Miller, Dianna Rose Szedlmayer Stephen T. "A comparison of fish and epibenthic assemblages on artificial reefs with and without copper-based anti-fouling paint". Auburn, Ala, 2008. http://repo.lib.auburn.edu/EtdRoot/2008/SPRING/Fisheries_and_Allied_Aquacultures/Thesis/Miller_Dianna_26.pdf.
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16
Ruhl, Henry A. "Climate and food supply influences on mobile epibenthic megafauna populations in the abyssal NE Pacific from 1989 to 2004". Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2006. http://wwwlib.umi.com/cr/ucsd/fullcit?p3213081.
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Thesis (Ph. D.)--University of California, San Diego, 2006.Title from first page of PDF file (viewed June 27, 2006). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references.
17
Nickell, Thomas Diedrich. "Behavioural ecology of epibenthic scavenging invertebrates in the Clyde Sea area : laboratory experiments on attractions to bait in static water". Thesis, University of London, 1989. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.551284.
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Lauerman, Lynn M. L. "Deep-sea epibenthic echinoderms and a temporally varying food supply : results from a long time-series study in the abyssal N.E. Pacific /". Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 1998. http://wwwlib.umi.com/cr/ucsd/fullcit?p3035417.
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Dias, Maria Inês Rocha Maia. "Epifaunal biodiversity of gorgonians from the South of Portugal". Master's thesis, Universidade de Aveiro, 2012. http://hdl.handle.net/10773/12501.
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Mestrado em Biologia Aplicada - ramo Biologia MarinhaGorgonians are sessile cnidarians with a three-dimensional and complex structure that plays a relevant ecological role in coastal ecosystems, providing physical habitat, refuge and food sources for other small organisms. Despite their relevance as foundation species, very few studies have addressed the ecological patterns of hosts (gorgonians) and their attendant fauna. The present study aims to analyse the temporal variability of the epifaunal assemblages associated with two of the most abundant gorgonian species from southern Portugal, Eunicella gazella and Leptogorgia lusitanica. As gorgonian populations comprise colonies of different sizes, ecological patterns of attendant assemblages were also analysed with regards to colony size (3 size classes). Replicate samples were collected in July and November 2010, March, June and August 2011 in Pedra da Greta (Algarve, Portugal). The results suggest that the gorgonian host exert a significant effect on the composition and structure of the attendant epifaunal assemblages, although most taxa were common to both hosts. Time, more than size, was found to be a main driver of the ecological patterns of these assemblages, where amphipods, molluscs and polychaetes were the more abundant and richest groups. The temporal patterns were characterized by high densities and diversity in the attendant epifaunal assemblages during spring-summer, followed by a high mortality or emigration of rare and occasional taxa, leading to a sharp decrease in the values of biodiversity and abundance indicators. During the autumnwinter period, the assemblages were mainly dominated by the resident taxa (i.e. taxa present in all sampling dates). After the peak of phytoplankton observed during this period and as the seawater temperature increased, the spring recolonization contributed to the re-establishing of rich and abundant assemblages that persisted during the summer. Therefore, temporal variability must be taken into account for the design of future biodiversity assessment studies, as different patterns may be observed depending on the sampling time.
As gorgónias são organismos sésseis que devido à sua estrutura complexa e tridimensional desempenham um papel ecológico importante nos ecossistemas costeiros, proporcionando substrato físico, local de refúgio e fonte de alimento a outros organismos. No entanto, apesar da sua importância como espécies estruturantes, poucos estudos têm tido em consideração os padrões ecológicos, tanto das gorgónias como da sua fauna associada. Este estudo tem como principal objectivo analisar os padrões temporais da fauna epibentónica de duas das gorgónias mais abundantes do sul de Portugal, Eunicella gazella e Leptogorgia lusitanica. Devido à diferença no tamanho das colónias de gorgónias presentes, os padrões ecológicos da sua fauna associada foram analisados considerando 3 classes de tamanho. Tendo como objectivo averiguar flutuações temporais, as amostras foram recolhidas em Julho e Novembro de 2010, Março, Junho e Agosto de 2011 na Pedra da Greta (Algarve). Os resultados observados, indicam que o organismo hospedeiro exerce um efeito importante na composição e estrutura da comunidade associada, ainda que a maioria dos taxa seja comum às duas gorgónias. Não obstante, com maior influência que o tamanho da colónia, a variabilidade temporal, foi considerada o principal contribuinte para a explicação dos padrões ecológicos observados na fauna associada, na qual anfípodes, moluscos e poliquetas foram os grupos mais ricos e comuns. Os padrões temporais foram caracterizados por uma elevada densidade e diversidade da epifauna no período Primavera-Verão, seguida de uma elevada mortalidade ou emigração de taxa raros ou ocasionais, resultando num decréscimo dos valores das variáveis biológicas. Durante o período Outono-Inverno, a comunidade foi maioritariamente dominada por taxa residentes (ou seja, taxa presentes em todos os períodos de amostragem). Após o aumento da abundância de fitoplâncton observado neste período e à medida que a temperatura da água aumenta, a recolonização durante a Primavera contribui para o restabelecimento da comunidade rica e abundante do Verão. Assim, a variabilidade temporal é um factor a ter em conta na elaboração de estudos de biodiversidade, visto ser provável a ocorrência de diferenças significativas durante o período de amostragem.
20
Stocks, Holly Stephanie. "A Survey of the Taxonomy of the Cyanobacteria from Northeast Florida, Descriptions of Novel Taxa, and an Investigation into the Factors Which Influence the Epibenthic Cyanobacterial Community". UNF Digital Commons, 2013. http://digitalcommons.unf.edu/etd/480.
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Cyanobacteria are important components of the aquatic system, valued for their oxygen production, nitrogen fixation, and as the base of many aquatic food webs. This study investigated several aspects of cyanobacteria such as the diversity and response to nutrient enrichments. A survey of Northeast Florida was conducted between the years of 2010 and 2012; a total of 145 taxa were identified in freshwater habitats, such as springs, lakes, rivers, and retention ponds. While surveying the St. Johns River in Jacksonville, Florida, a novel Stigonematalean taxon was isolated and cultured. Subsequent morphological and genetic analyses indicate that this taxon is related to Fischerella, Nostochopsis, and Westelliopsis, though with poor bootstrap support. Thus, a new genus and species (Reptodigitus chapmanii gen. et sp. nov.) is proposed. Cyanobacterial community shifts are increasingly being employed as an indicator of ecosystem health. The last part of this study is an experimental manipulation of nutrients and subsequent community analyses. Chlorophyll a, total number of cells, and Dmax were significantly different between control groups and nutrient enriched groups. Phosphate was not strongly correlated to species richness, chlorophyll a, evenness, total number of cells, species richness, or diversity in either the control or the nutrient enriched groups. Nitrogen displayed similar results, though it was slightly more strongly correlated to evenness and diversity in the nutrient enriched group than the control group. The results of the survey and nutrient enrichment experiment are important parts of the investigation into how cyanobacterial communities respond to changes in nutrient concentrations, which can then be used to devise a standard metric against which water management agencies can compare to determine the health of a given aquatic system.
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Feldman, Kristine Ladyka. "Contrasting patterns of habitat-specific recruitment success in sympatric species of thalassinidean shrimp : effects of epibenthic bivalve shell with implications for population control in areas with commercial oyster culture /". Thesis, Connect to this title online; UW restricted, 2001. http://hdl.handle.net/1773/5321.
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Suck, Inken [Verfasser]. "Spatial and temporal variability of North Sea mega-epibenthos assessed by seabed photography. / Inken Suck". 2008. http://d-nb.info/990361942/34.
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Polte, Patrick [Verfasser]. "Ecological functions of intertidal seagrass beds for fishes and mobile epibenthos in the northern Wadden Sea / Patrick Polte". 2004. http://d-nb.info/979700191/34.
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Chen, Hsu-sen, i 陳煦森. "Assemblages of epibenthic shrimps in coastal waters off Southwestern Taiwan". Thesis, 2006. http://ndltd.ncl.edu.tw/handle/61271430098879990399.
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碩士國立中山大學
海洋生物科技暨資源學系研究所
94
This study is aiming to investigate the distribution of epibenthic shrimp communities in relation to the environmental factors of their habitats in the coastal sandy bottom of southwestern Taiwan. Shrimp samples were collected from April 2002 to July 2003, with a beam trawl operated at seven stations along the coasts. Simultaneously, water temperature, salinity, dissolved oxygen were measured and sediments were collected. Particle size and organic matter of the sediments were then analyzed in the laboratory. The results of PCA analyses on these environmental factors revealed that the observations could be segregated into two groups along the PC1, representing rainy season with high temperature, low salinity and dry season with low temperature, high salinity, respectively. The observations with coarse particle (>0.125 mm), representing samples from north sites, were found to distribute in the upper part of the PC2; while those with fine particle (<0.125 mm), representing samples from south sites, distributed in the lower part. In total, 15,591 individuals of shrimp were collected, including 20 genus, 39 species. Metapenaeopsis palmensis (88.2%), Trachysalambria curvirostris (3.6%), M. barbata (3.5%) and Parapenaeopsis cornuta (1.4%) were the four dominant species. Significant differences in the spatial distribution were due to the different composition of the dominant species. Although M. palmensis was the most abundant species in most stations, its percentage abundance was the lowest at Fangliao and Jiading, where the dominant species were T. curvirostris for the former and M. barbata and P. cornuta for the latter. Species preferences for various combinations of environmental variables are responsible for shifts in the structure and overall abundance of assemblages and dictated some patterns. Higher abundances of T. curvirostris, Trachypenaeus granulosus, and Solenocera koelbeli were associated with the appearance of high temperature, low salinity and very fine sand, representing the environmental features of Fangliao and Linbian during the rainy season. Stenopus hispidus, Metapenaeus moyebi, Metapenaeus ensis and M. palmensis were abundant coinciding with low temperature, high salinity and high silt and clay that reflecting the dry season of Linyuan and Linbian waters. Metapenaeopsis dalei and M. barbata appeared in large numbers at habitats with high temperature, low salinity and coarse sand, which mainly occurred in Zouying to Jhongjhou during the rainy season. Moreover, Scyllarus rugosus and Parapenaeopsis cornuta seemed to prefer coarse sandy bottom mainly distributed from Jiading to Linyuan. Temporal fluctuations were associated with the population dynamic of the dominant species. The abundance was reduced while the M. palmensis migrated to open sea in late summer and early autumn. As the juveniles of M. palmensis and M. barbata back to the inshore waters, the abundance were increased and reached the peak in spring. Because of the limited distribution, T. curvirostris and P. cornuta were not influence the overall temporal fluctuations but the local fluctuations. Overall, temporal fluctuations act more at a specific level even structural one, and may be linked to some particular stages of the benthic shrimp life cycle, but do not significantly influence the spatial organization.
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Chen, Hsu-Sen, i 陳煦森. "The ecology of epibenthic shrimps in the coastal waters offWestern Taiwan". Thesis, 2015. http://ndltd.ncl.edu.tw/handle/28104537269835620762.
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博士國立中山大學
海洋生物科技暨資源學系研究所
103
The aims of this study is to (1) establish the baseline information of the shrimp assemblages in the coastal area in order to map the biotopes, (2) elucidate how the environmental factors act on shrimp assemblages, (3) realize the reproductive season and information on the dominant species reproductive ecology and (4) combine the information on reproductive biology and hydrology to investigate the habitat usage during the life cycle history. Shrimp samples were collected twice per season from April 2002 to August 2010, with a beam trawl operated by R/V Ocean Researcher No. 3 at 10 stations, Wanggong, Taisi, Cigu, Jiading, Zouying, Jhongjhou, Linyuan, Dapeng, Linbian and Fangliao, in the western waters off Taiwan. Simultaneously, various environmental factors were also recorded by CTD. Meanwhile, we also collected the samples from fish market for reproductive biology study since January 2009 to December 2011. In total, 54,671 individual shrimp were obtained, including 12 families, 27 genera, and 53 species. Among the families, Penaeidae consisted of the most numerous species (25 species,), followed by Alpheidae (9 species) and Scyllaridae (5 species). Metapenaeopsis palmensis (49.1%), Parapenaeopsis hardwickii (29.8%), Parapeaneopsi cornuta (5.7%), Trachysalambria curvirostris (5.1%), and M. barbata (2.0%), were the numerically dominant species, contributing 91.7% of the total catches. There is significant spatial distribution in the waters off western Taiwan. The north group and south group were dominant by M. palmensis and P. hardwickii, respectively. This phenomena might be related to the year round current and water mass seasonal oscillation in the Taiwan Strait. The reproductive season of the dominant shrimp were all occur before rainy season when the water temperature exceeds 25˚C, and the juveniles were recruit after rainy season, only the larvae born in the late spawning season will successfully recruit in the dry season in September-November when the water salinity is higher than 33.5 psu, due to the low salinity and turbid water during the rainy season.
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Lin, Jen-Chieh, i 林仁杰. "A Study of Epibenthic Invertebrate Community in the Shelf Break Region off Southwestern Taiwan". Thesis, 2014. http://ndltd.ncl.edu.tw/handle/06882585772382820943.
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碩士國立中山大學
海洋生物科技暨資源學系研究所
102
To understand the epibenthic invertebrate community on the contential shelf break of southwestern Taiwan, we had sampled along the shelf break from Yongan to southern Penghu with beam trawl. Sampling was more intensively around nature gas drill site planed by China Petroleum Corporation. Dominant species were Cnidaria and Arthropoda in this area. The distribution of dominant species was different from inshore to offshore. The composition of dominant species group of offshore area were more homogeneous than that of inshore area. The abundance of Cnidaria was positively correlated to the number of species, abundance, diversity, and richness of the sampling site. Cnidaria appeared mostly on offshore, which including Bellonella sp., Epizoanthus ramosus, Actiniaria sp., Tropidocyathus lessonii, Flabellum distinctum and Flabellum sp.. Furthermore, Parapagurus Diogenes, Actumnus sp. and Polychae sp.2 showed high co-occurrence with Cnidaria in spatial distribution. Results of multivariate analysis showed heterogeneity in community structure among inshore and offshore. Community composition of offshore can be seperated into 3 subgroups, which were western Penghu Channel, eastern Penghu Channel, and area around nature gas drill. These findings revealed a significant influence of environment condition and topography on the composition of benthic community. The dominant species of inshore area were Portunus spp. and Parapenaeopsis spp.. The dominant species of western Penghu Channel were Portunus spp., Metapenaeopsis spp., Sepia sp., and Philine sp.. The dominant species of eastern Penghu Channel were Flabellum spp., T. lessonii, Alcyonacea spp., and E. ramosus. The dominant species of area around nature gas drill were E. ramosus, Actiniaria sp., T. lessonii, and Parapagurus Diogenes.
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Chu, Jackson Wing Four. "Influence of seasonally variable hypoxia on epibenthic communities in a coastal ecosystem, British Columbia, Canada". Thesis, 2016. http://hdl.handle.net/1828/7182.
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Natural cycles of environmental variability and long-term deoxygenation in the ocean impose oxygen deficiency (hypoxia) on marine communities. My research exploits a naturally occurring hypoxia cycle in Saanich Inlet, British Columbia, Canada where I combined spatial surveys with remotely operated vehicles, ecological time-series from the subsea cabled observatory VENUS, and lab-based respirometry experiments to examine the influence of seasonally variable oxygen conditions on epibenthic communities.
In situ oxygen thresholds established for dozens of fish and invertebrate species in this system show they naturally occur in lower oxygen levels than what general lethal and sublethal thresholds would predict. Expansion of hypoxic waters induced a loss of community structure which was previously characterized by disjunct distributions among species. Communities in variable hypoxia also have scale-dependent structure across a range of time scales but are primarily synchronized to a seasonal oscillation between two phases. Time-series revealed timing of diurnal movement in the slender sole Lyopsetta exilis and reproductive behavior of squat lobster Munida quadrispina in the hypoxia cycle. Hypoxia-induced mortality of sessile species slowed the rate of community recovery after deoxygenation. The 10-year oxygen time-series from VENUS, revealed a significant increase in the annual low-oxygen period in Saanich Inlet and that deoxygenation has occurred in this system since 2006. Differences in the critical oxygen thresholds (O2crit) and standard metabolic rates of key species (spot prawn Pandalus platyceros, slender sole, and squat lobster) determined the lowest in situ oxygen at which populations occurred and explained disproportionate shifts in distributions and community respiration. Finally, a meta-analysis on global O2crit reported for crustaceans showed that hypoxia tolerance differs among major ocean basins.
Long-term trends of deoxygenation suggest a future regime shift may occur when the duration at which a system remains below critical oxygen levels exceeds the time needed for communities to recover. Species-specific traits will determine the critical threshold and the nature of the community response in systems influenced by variable states of oxygen deficiency. However, oceanographic and evolutionary history provides context when determining the regional response of benthic communities influenced by rapidly changing environments.Graduate
0329
0416
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jwfchu@gmail.com
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Chen, Tzu-Chun, i 陳姿君. "Assemblages of epibenthic crabs and spatiotemporal distribution of dominant species in coastal waters off southwestern Taiwan". Thesis, 2010. http://ndltd.ncl.edu.tw/handle/45546805877218284872.
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碩士國立中山大學
海洋生物科技暨資源學系研究所
98
The present study used beam trawl net to collect crabs by Ocean Researcher III at four sites, Wanggong, Taisi, Cigu and Jiading, in western waters off Taiwan from July 2006 to October 2008. In total, 3205 crabs were obtained, including 11 families, 22 genus, 41 species and 6 unknown species. Among these families, Portunidae contained the most species (21 species, 45％), followed by families Majidae (4 species, 9%), Leucosiidae (3 species, 6%) and Dorippidae (3 species, 6%). Six dominant species were Portunus hastatoides (60.1%), Portunus argentatus (13.7%), Portunus sanguinolentus (7.2%), Matuta victor (3.8%), Charybdis truncata (3.0%) and Portunus pelagicus (2.1%) contributing 89.8% of the total catch. P. sanguinolentus (35.6%), P. pelagicus (16.3%), P. hastatoides (12.0%), Calappa philargius (11.5%), P. argentatus (8.0%) and Charybdis feriatus (3.1 %) were the six dominant species (86.5%) by biomass. Spatial distributions of the benthic crabs by number were significantly different. P. argentatus was the most dominant species in Cigu, whereas in the other three stations was P. hastatoide. Among the six species, P. sanguinolentus, P. pelagicus and C. feriatus are the most important species in terms of economic value. The former appeared in large numbers in Jiading and composed 35.6% in weight of the total catch from all sites, while the latter frequently occurred in the other three sites and contributed 16.3% to the overall sample weight. Moreover, P. sanguinolentus was the dominant species in terms of weight in Jiading, but the rest of three sites dominated by P. pelagicus. P. hastatoides occurred mostly in the substrate with very fine sand. P. sanguinolentus increased in number and weight with decreasing of salinity and water depth. P. argentatus had a narrowest optimum temperature range from 24.3 to 28.3℃.
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Raguá, Gil Juana Marianne [Verfasser]. "Shallow water mega epibenthic communities in the high Antarctic (Weddell Sea) and the west coast of the Antarctic Peninsula (Bellingshausen Sea) / Juana Marianne Raguá Gil". 2004. http://d-nb.info/975492969/34.
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Wei, Chih-Lin. "Standing Stocks and Faunal Zonation of Deep-Sea Benthos: Patterns and Predictions across Scales". Thesis, 2011. http://hdl.handle.net/1969.1/ETD-TAMU-2011-05-9423.
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The deep ocean (> 200-m depth) covers more than 65 percent of earth's surface and is known as the largest active carbon sink of the planet. Photosynthesis fixes inorganic carbon into organic rich-compounds to fuel the biological production in the upper ocean. A small portion of the photosynthetic carbon eventually sinks to the seafloor to support diverse deep-sea life. In this dissertation, the phytoplankton production and export flux of particulate organic carbon (POC) to the seafloor were linked to standing stocks and compositional changes of the deep-sea soft bottom assemblages. The pattern and processes of energy transfer from the surface ocean to the deep sea was examined by modeling the global benthic bacteria, meiofauna, macrofauna, and megafauna biomass from remotely sensed ocean color images and the seafloor relief. The analysis was then scaled down to the macrofauna of the Gulf of Mexico (GoM) to examine the global pattern on regional oceanic features with contrasting productivity regimes. These results suggested a universal decline of benthic standing stocks down the continental margins that is caused by an exponential decrease of export POC flux with depth. A revisit of historical epibenthic invertebrate sampling in the North Atlantic showed that both individual species and multi-species assemblages occurred in narrow depth bands that hugged the topography from the upper continental slope out to the Hatteras Abyssal Plain. The continuum compositional change suggested that the continuous decline of benthic food supply with depth was the potential driving force for the pattern of bathymetric faunal zonation. A broad, systematic survey across multiple depth transects in the northern GoM suggested that macrofauna zonation is not only taking place across isobaths, but also form the northeast to the northwest GoM due to a horizontal productivity gradient created by the nutrient-laden Mississippi River. Analyses of long-term demersal fish data from 1964 to 2002 in the northern GoM showed no evidence of large-scale faunal change across different sampling times. Base on the pooled data, a shift in rate of fish species replacement may be caused by complex biological interactions or changes in environmental heterogeneity along depth or productivity gradients.