Dissertations / Theses on the topic 'Intertidal ecology'
To see the other types of publications on this topic, follow the link: Intertidal ecology.
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 dissertations / theses for your research on the topic 'Intertidal ecology.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
1
Chavanich, Suchana. "Rocky intertidal zonation and habitat ecology of gammaridean Amphipods in Long Island Sound /." Click for abstract, 1997. http://library.ctstateu.edu/ccsu%5Ftheses/1484.html.
Full textAbstract:
Thesis (M.A.)--Central Connecticut State University, 1997.Thesis advisor: Dr. Kim A. Wilson. " ... in partial fulfillment of the requirements for the degree of Master of Arts in Biology." Includes bibliographical references (leaves 47-56).
2
Ramon, Marina L. "Molecular ecology and evolution of intertidal sculpins /." Diss., Digital Dissertations Database. Restricted to UC campuses, 2007. http://uclibs.org/PID/11984.
Full text
3
Murias, dos Santos Antonio E. Ferrand de Almeida. "Intertidal ecology of northern Portuguese rocky shores." Thesis, University of Southampton, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.326590.
Full text
4
McGary, Cara L. "A long term comparison of rocky intertidal communities in Redwood National and State Parks /." California : Humboldt State University, 2005. http://hdl.handle.net/2148/22.
Full text
5
Tong, Lily K. Y. (Lily Kit Ying). "The population ecology of the intertidal bivalve Lasaea australis." Phd thesis, Faculty of Arts, 1990. http://hdl.handle.net/2123/9035.
Full text
6
Dunmore, Robyn Ann. "Demography of early life stages of habitat-forming intertidal fucoid algae." Thesis, University of Canterbury. Biological Sciences, 2006. http://hdl.handle.net/10092/1364.
Full textAbstract:
The intertidal zone is finely partitioned in species distributions and abundances. The demographies of key species over varying spatial and temporal scales are fundamental to understanding the population structure and overall dynamics of habitats and assemblages. In this thesis, settlement, dispersal and early life stage survival and growth were examined in several habitat-forming intertidal fucoid algae in New Zealand and Oregon, U.S.A. Natural settlement patterns of Hormosira banksii, Cystophora torulosa and Cystophora scalaris were quantified for over three years at a semi-protected shore in southern New Zealand. Settlement was monitored in four tidal zones, within bare rock and algal habitats. Settlement was synchronous between tidal zones but the density of settlement varied spatially and temporally. There were significant differences between tidal zones, habitats and times of the year. For H. banksii, small pulses of settlement occurred year-round with greatest densities during spring and early summer. Greatest settlement occurred at low tidal zones and under adult canopies. Both Cystophora species also reproduced year-round, but had much lower settlement densities than H. banksii. Most settlement occurred during spring and summer, while only small pulses occurred in autumn and winter months. Most settlement was in the lowest tidal zone (0.4 m above chart datum), with only a few zygotes settling at higher shore zones. Canopy cover had no significant effect on settlement densities. Dispersal was examined in Durvillaea spp., H. banksii, C. torulosa and Fucus gardneri. For all species, settlement densities declined with distance from the source populations, but densities were variable between species. Durvillaea spp. dispersal was more extensive than expected, with significant settlement occurring 32 m from the source population, the maximum sample range of the study. However, settlement densities were much higher within 8 m from the source. The extensive dispersal of Durvillaea spp. is a result of the combination of small, slowly sinking eggs and the presence of buoyant mucilage. The other species studied showed far more restrictive dispersal, and much lower settlement densities. Settlement occurred 2 m from the source, but most settlement occurred under or near the canopy. The eggs of these species are much larger and sink faster than the eggs of Durvillaea spp. The consequences of settling at different shore heights and seasons were examined in H. banksii and D. antarctica in New Zealand, and F. gardneri and Pelvetiopsis limitata in Oregon. Transplant experiments tested the effects of grazing and heat/desiccation stress on survival and growth of germlings at different shore heights, during different seasons. High germling mortality was a feature of all species, but rate of mortality depended on conditions and species. There is a trade-off for settling at different times of the year; overall, growth was faster in warmer seasons, but survival was better in cooler seasons. During cooler seasons, germlings are exposed to less heat/desiccation stress, but their slow growth exposes them to grazing and competitive interactions for longer periods. For New Zealand species, shore height had large effects, with better survival and growth in the low shore. Grazers were very effective in the low shore, and heat/desiccation stress had strong effects in the mid and high shores. For Oregon species, effects of grazing and heat/desiccation stress were generally weaker than for New Zealand species. Shore height had weak effects, but ultimately low shore germlings had poor survival, primarily because of overgrowth by ephemeral algae. This is in contrast to the generalisation that survival and growth in the low shore should be better due to a more benign environment. In this study, species had specific demographies that related to their life history characteristics and responses to the local environment. Differences in settlement, dispersal abilities, survival and growth over small spatial and temporal scales clearly underpinned large scale differences in recruitment and adult distribution and abundances.
7
Ragnarsson, Stefan Aki. "Successional patterns and biotic interactions in intertidal sediments." Thesis, University of Aberdeen, 1996. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU078135.
Full textAbstract:
The main objective of this thesis was to investigate the role of biotic interactions, biogenic structures and successional patterns in several invertebrate soft bottom assemblages in the Ythan estuary, Aberdeenshire, Scotland. The seasonal dynamics of the fauna found within a dense tube-field of Lanice conchilega were investigated. The abundance and composition of this fauna differed from that in the adjacent sediments and from that in the nearby sandflat at Red Inches. No consistent differences in abundance could be detected for any species throughout the tube-field, and the mussel (Mytilus edulis) was the only species significantly positively correlated with Lanice tube density. Pygospio elegans was found in significantly reduced numbers in tube-field areas affected by weed. Accumulation of weed and subsequent settlement of mussels in summer and periodical intense sediment movement during winter may have partly accounted for the large seasonal fluctuations seen in the abundance and composition of the tube-field fauna. The size of distributed patches is thought to influence the rate of colonization, but there have been few experimental tests of this proposition. The hypothesis was therefore tested by a field experiment where the rates and modes of colonization of azoic patches of different size (1600cm2 vs. 55cm2) were compared. The results of this experiment were also considered when designing subsequent experiments (see below). None of the invertebrates recorded differed significantly in abundance between patch size on any sampling occasion. The total number of species and individuals rapidly attained control (natural sediment) values. However, the patterns of colonization of individual species could be categorised into three types. The abundances of Type I species mirrored closely those in control sediments. Type II species were opportunists, such as the polychaete Capitella spp., which exceeded the control density rapidly but then showed a decline. Type III species, such as the polychaete Pygospio elegans, showed a very slow increase in azoic areas and never attained control densities, although size distributions were markedly different between the two patch sizes. This experiment showed that over the range studied, size of patch was not important in determining overall colonization patterns on sandflats.
8
Hurd, Catriona L. "The physiological ecology of nutrient uptake by intertidal fucoid algae." Thesis, Queen's University Belfast, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.332658.
Full text
9
Soares, Alexandre Goulart. "Sandy beach morphodynamics and macrobenthic communities in temperate, subtropical and tropical regions : a macroecological approach." Thesis, University of Port Elizabeth, 2003. http://hdl.handle.net/10948/293.
Full textAbstract:
A comprehensive study involving 52 microtidal beaches spanning from reflective to dissipative states and located in tropical, subtropical and temperate regions in the Atlantic, Pacific and Indian oceans was carried out to unravel the relative roles of latitude and beach morphodynamics in determining beach macrobenthic species richness, abundance, biomass and mean individual body sizes. Since beach slope is one of the most important factors controlling beach fauna, a model based on beach geometry was applied to the sub-aerial beach deposit to understand the role of physical factors in predicting equilibrium beach slopes. Additionally, it was tested if the occurrence of beach types is related to latitude, and how physical factors change with morphodynamics and latitude. The beach morphometric model makes three assumptions: 1) that the cross-section of a beach deposit is equivalent to a right-angled triangle, 2) that the physical hydrodynamic factors (wave height and spring tide amplitude) and the beach deposit characteristics (sand grain size, beach slope and width) are interchangeable with their geometric counterparts producing an equation to explain beach geometry, and 3) that the predicted beach slope is in equilibrium with the hydrodynamic and sedimentological forces. The equation for predicting beach slope was derived and then tested against field data collected over 52 beaches. The predicted slopes were not significantly different from the observed slopes of the studied natural beaches. However some estimated slopes were different than observed ones. Possible sources of deviation between calculated and observed slopes may be the systematic sampling errors associated with field data. Alternatively, observed slopes could be the result of past hydrodynamic conditions, explaining the differences with the slopes calculated by the beach morphometric model, which assumes a state of equilibrium between beach slope and hydrodynamic conditions. A higher correlation of beach faunal structure with observed slopes rather than with present hydrodynamic conditions could then be indicative of faunal responses to previous hydrodynamic conditions in the same way was the observed slopes. The beach morphometric model could therefore be also useful in predicting faunal responses to changing hydrodynamic conditions. Since the model does not consider wave period, it is concluded that further tests should be done using laboratory and time-series field data and incorporating the role of wave period and beach permeability to ascertain its predictive value. Tropical regions had significantly more beaches in a reflective state than temperate and subtropical regions. Some tropical beaches were fronted by coral reefs, which not only provided coarse carbonate particles, but also additionally dissipated the low wave energy present in these climatic areas. Only one dissipative beach with high energy was found in the tropics, in southeast Madagascar. Temperate and subtropical regions, on the other hand, were dominated by dissipative beaches with medium to fine sands. Open oceanic reflective beaches were non-existent in the subtropics and rare in temperate regions, only occurring in estuaries, enclosed bays or on islands facing the continent. Intermediate beaches were more common in the subtropics but also occurred frequently in the other two regions, having higher energy in temperate regions. Reflective beaches had significantly steeper slopes, coarser sands, smaller waves and shorter swash lengths when compared to dissipative beaches. Additionally, reflective beaches were narrower, had deeper water tables and in consequence shorter saturation zones. Wave periods and surfzone widths were on average larger on dissipative than on reflective beaches. The frequency of occurrence of beach types is therefore related to the climatic signature of each latitude. Mid latitudes would be predicted to have more dissipative beaches with large and long waves because of their proximity to the storm generating belt around 50-60° S - these beaches will have a predominantly finer sands because of the input by rivers in rainy areas. Lower latitudes will have more reflective beaches due to a modal low energy wave climate and also because of the presence of inshore and offshore biotic structures such as coral reefs that dissipate even more the energy from the waves. Tropical and subtropical regions had larger marine species pools than temperate regions. After controlling for biogeographical differences in total species pool, dissipative beaches were on average significantly richer than intermediate and reflective beaches. Crustaceans were also more diverse on dissipative beaches, this difference being not significant for either molluscs or polychaetes. Significant relationships were found between total beach species richness (with or without terrestrial species), crustacean and mollusc species richness with beach morphodynamics as represented by the Dean’s index. Indices incorporating the role of tide, such as BSI, were less important in predicting species richness on the microtidal beaches studied here. Several other physical factors were also significantly correlated with species richness, the most important being the Beach Deposit Index, i.e. BDI, a composite index of beach slope and grain size. The highest correlation was between BDI and relative species richness, i.e. local beach species richness / regional species richness. Total regional marine species richness was higher in Madagascar and North Brazil (tropical beaches) than in Southeast Brazil (subtropical), or the West Coast of South Africa and South-Central Chile (temperate beaches). Not only was the pool of species capable of colonizing beaches richer in tropical and subtropical regions, but also local diversity of each morphodynamic beach type was higher among tropical beaches than their temperate counterparts. Although the results of this study agree with the predictions of the swash exclusion hypotheses, several reflective and intermediate beaches had higher species richness than predicted before and this seems to be linked to the presence of finer sediments and a less turbulent flow for larvae to settle. It is concluded that beach species richness is not necessarily controlled by one major morphodynamic parameter; this control is complex and probably involves multiple interacting biotic (biological interactions) and abiotic (e.g. grain size, wave height, beach slope and width, water table) factors. Species richness seems to be controlled on two different scales: on an evolutionary one where tropical and subtropical regions have higher regional and local diversity due to higher speciation rates; and on an ecological scale, where fine grained sand beaches have their carrying capacity enhanced by higher larval settlement rates and survival of recruits towards adulthood. On average dissipative beaches had higher total densities and macrofaunal abundances than reflective ones. Crustaceans, terrestrial species and cirolanid isopods such as Excirolana spp. were also more abundant on dissipative beaches. The difference was not significant for molluscs and polychaetes. Significant relationships were found between total abundance, crustacean species richness and beach morphodynamics as represented by the Dean’s index. Again, BSI was less important than individual physical factors in determining faunal abundance on the studied microtidal beaches. Several other physical factors were also significantly correlated with abundance, the most important being the Beach Deposit Index (BDI). The highest correlation was between BDI and total macrofaunal abundance. Factors related to surf zone processes, and possibly productivity, were highly correlated with total community, crustaceans, Excirolana spp. and terrestrial species abundances. The abundances of polychaetes and molluscs were better correlated with factors related to the beach deposit (BDI, slope, grain size and water table depth). Significant differences were observed between latitudinal regions for the average beach and also for each beach type. In general temperate beaches harboured larger community densities and abundances, and also crustacean, Excirolana spp. and terrestrial abundances. Mollusc and polychaete abundances were larger on subtropical and tropical beaches. The control of abundance on a sandy beach is complex and involves multifactorial processes at evolutionary and ecological scales. At evolutionary scales animals seem to attain higher abundances in the region where they first evolved, e.g. amphipods and isopods in temperate regions. At ecological scales they attain higher abundances where productivity is higher (total macrofaunal, crustaceans, Excirolana spp., terrestrial spp.) or where the settlement environment is more benign (molluscs and polychaetes). Dissipative beaches supported larger average and total community biomass than reflective beaches. Crustaceans, terrestrial species and cirolanid isopods such as Excirolana spp. also had larger biomass on dissipative beaches. The difference was not significant for molluscs and polychaetes. Significant relationships were found between the biomass of community and taxonomic groups with beach morphodynamics as represented by the Dean’s morphodynamic index. On the microtidal beaches studied here, BSI was less important than other morphodynamic indices and single physical factors in determining faunal biomass and mean individual body size. Surf zone characteristics such as wave height, period and surf zone width had the highest correlations with community, crustacean.
10
Dower, Katherine Mary. "Sand inundation on rocky shores : its effects on species richness and the structure of species assemblages." Thesis, Rhodes University, 1990. http://hdl.handle.net/10962/d1007183.
Full textAbstract:
Although sand deposits are present on many intertidal rocky shores, their effects on species richness, zonation and trophic structure have often been overlooked. This study is the first to recognise sand as an important abiotic factor on South African rocky shores. Rocky shores in the eastern Cape Province of South Africa are subject to extensive sand inundation and are composed of two hard substrata of differing topographies. Four sites on one substratum and six on the other were sampled quantitatively using quadrats. The biota were identified, counted and/ or weighed to provide a matrix of species biomass and numbers in separate zones. This matrix was then analysed using ordination and classification. A total of 321 species were identified which is more than local rocky or sandy shores. While the intermediate disturbance hypothesis would predict high species richness on these shores, it does not fully explain this richness nor the distribution of species assemblages. Habitat heterogeneity, including the dynamics of sand deposits, is strongly influenced by substratum topography and is the most important factor generating species richness. Abrasion by sand (sand scour) causes local reductions in richness but the presence of semi-permanent sand deposits allows habitation by psammophilic and sand-dependent species. As a result the biota of a sand inundated rocky shore includes both a full rocky shore and a large sandy beach component. Substratum topography controls patterns of sand deposition and retention and community analysis showed that samples were clustered primarily according to species richness and secondarily according to substratum type. Ordination of species identified an arc of species assemblages of decreasing levels of sand tolerance. These corresponded to sample groupings so that th assemblages found in various habitats were characterised by particular levels of sand tolerance. The presence of sand has a negative effect on the biomass of primary producers and filter feeders but a positive effect on the biomass of deposit feeders. Because sand is retained to different degrees in different zones, trophic structure varies between zones and to a lesser extent, between rock types. In general, however, the trophic structure of sand inundated rocky shores is similar to that of non-inundated shores.
11
Nagarkar, Sanjay. "The ecology of intertidal epilithic biofilms with special reference tocyanobacteria." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1996. http://hub.hku.hk/bib/B31236054.
Full text
12
Pannacciulli, Federica Gabriella. "Population ecology and genetics of European species of intertidal barnacles." Thesis, University of Liverpool, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.295815.
Full text
13
Austin, Heather Anne. "The biology and ecology of benthic foraminifera inhabiting intertidal mudflats." Thesis, University of St Andrews, 2003. http://hdl.handle.net/10023/7099.
Full textAbstract:
Benthic foraminifera inhabiting the mudflats of the Eden Estuary, NE Scotland, exhibited a single annual peak in abundance at both high (270 individuals 10 cm⁻²) and low shore (210 individuals 10 cm⁻²) intertidal sampling stations during June 2000. The increased total abundance coincided with reproduction in the two dominant foraminiferal species Elphidium williamsoni (May) and Haynesina germanica (June) at both sites. Benthic diatom biomass, measured as chlorophyll c, peaked at the high intertidal site during March and April 2001 (36 and 37 mg m cm⁻², respectively) and at the low intertidal site in June2000 (45 mg m cm⁻²). The high intertidal foraminiferal populations appeared to display a lagged response to increases in chlorophyll c. Multivariate statistics suggest that abiotic factors control the abundance of foraminifera at the high intertidal site. At the low intertidal site, total foraminiferal abundance demonstrated an almost immediate response to increased chlorophyll c and multivariate statistics suggested biotic factors are more important in controlling foraminiferal species abundance here. Ingestion rates of ¹³C-Iabelled benthic diatoms over a five-day experimental period were high (e.g. enrichment values for Elphidium were recorded as 687 ± 121 % after 1 day) in intertidal benthic foraminifera. Laboratory observations of E. williamsoni demonstrated rapid asexual reproduction (within 3 days) and growth rates of up to 14 µm day⁻¹ were estimated. Three benthic foraminiferal species E. williamsoni, H germanica and E. oceanensis ingest motile benthic diatoms as a food resource on the intertidal mudflats of the Eden Estuary. Novel application of natural abundance stable isotope (δ¹³C and δ¹⁵N) techniques demonstrated the trophic position of intertidal benthic foraminifera, confirming that they largely ingest and assimilate organic matter derived from benthic diatoms. Foraminifera have largely been overlooked in meiofaunal studies, but play a significant role in the rapid transfer of autotrophic carbon to higher trophic levels within benthic marine food webs.
14
Pfister, Catherine Ann. "The dynamics of fishes in intertidal pools /." Thesis, Connect to this title online; UW restricted, 1993. http://hdl.handle.net/1773/5255.
Full text
15
Hidas, Eszter Zsofia. "The patterns of abundance and demography of rocky intertidal marine invertebrates indicate that recruitment can set geographical range limits." Access electronically, 2007. http://www.library.uow.edu.au/adt-NWU/public/adt-NWU20080917.090811/index.html.
Full text
16
Cressman, Kimberly A. "Effects of intertidal oyster reefs on water quality in a tidal creek ecosystem /." Electronic version (PDF), 2003. http://dl.uncw.edu/etd/2003/cressmank/kimberlycressman.pdf.
Full text
17
in, John Kevin John. "The status and ecology of the intertidal gastropod littorina neglecta bean." Thesis, University of Leeds, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.510013.
Full text
18
Nagarkar, Sanjay. "The ecology of intertidal epilithic biofilms with special reference to cyanobacteria /." Hong Kong : University of Hong Kong, 1996. http://sunzi.lib.hku.hk/hkuto/record.jsp?B19667218.
Full text
19
Holmes, Sebastian Paul. "Interactions between settling organisms and molluscs in the rocky intertidal." Thesis, University of Sunderland, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.285280.
Full text
20
Piller, Leanne M. "An intertidal monitoring program for Mobil, Port Stanvac (Sth. Australia) : anthropogenic versus natural disturbance /." Title page, contents and abstract only, 1998. http://web4.library.adelaide.edu.au/theses/09SM/09smp6407.pdf.
Full text
21
Fletcher, Helen. "The impact and management of visitor pressure on Rocky Shore communities." Thesis, University of Newcastle Upon Tyne, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.363528.
Full text
22
Waung, I.-Hui. "Effect of patch-size and habitat-edges on intertidal distributions of microgastropods." Thesis, The University of Sydney, 2006. https://hdl.handle.net/2123/28116.
Full textAbstract:
With increasing human activity and urban development along coastal areas, much research has recently focussed on examining how fragmentation of habitats affect marine fauna in near-shore environments. This study examines relationships between density of populations and patch-size and the effect of edges of habitat on distributions of minute gastropods (microgastropods) living in patches of coralline algae on intertidal shores in south-eastem Australia.
23
Manley, Nicola Louise. "Polyphenolic compounds in intertidal fuciod algae and their effectiveness as grazing deterrents." Thesis, University of Liverpool, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.333575.
Full text
24
Moschella, Paula Serena. "The role of rock substratum in the ecology of intertidal epilithic biofilms." Thesis, University of Southampton, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.273750.
Full text
25
Cooper, Erin Elaine 1981. "Population biology and reproductive ecology of Chlorostoma (Tegula) funebralis, an intertidal gastropod." Thesis, University of Oregon, 2010. http://hdl.handle.net/1794/10916.
Full textAbstract:
xv, 99 p. : ill. (some col.) A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number.The trochid gastropod Chlorostoma (Tegula) funebralis is found in rocky intertidal habitats along the west coast of North America from Baja California to Vancouver Island. Size-frequency distributions of populations were analyzed along a latitudinal gradient from northern Oregon to Baja California. Populations in California and southern Oregon were dominated by individuals in the juvenile size classes (0.1g-2g). Along the Oregon coast, populations dominated by juveniles were correlated with coastline topography, with protected areas having large numbers of juveniles and exposed areas dominated by larger size classes. The largest size classes (>9g) were rarely present in southern populations. The seasonality of reproduction was investigated in a southern California population and an Oregon population to determine whether continuous reproduction in southern populations increases recruitment success over the year and decreases inter-annual variation in reproductive success. Constant recruitment may cause populations to have a large number of juveniles, the observed pattern in southern populations. Although individuals capable of reproduction were found year-round in both populations, the southern population experienced multiple spawning events over the year, while the northern population experienced only one such event. Constant recruitment may be a strategy to compensate for shorter life spans and smaller sizes of individuals in southern California. To investigate whether variations in predation rates on large adult C. funebralis affect the size structure of populations, the main predators and predation rates for different populations in Oregon were identified. All observed predation events were by the intertidal seastar Pisaster ochraceus . Predation pressure by P. ochraceus varied significantly with site and between sampling dates but did not remove enough C. funebralis from the adult population to have a significant effect on population size structure. To determine the connectivity between populations and the maximum dispersal potential, the mitochondrial gene COI was sequenced from individuals from nine populations ranging from southern California to northern Oregon. Although haplotype diversity was high, no genetic structure was found between populations. Rather than an indication of high dispersal potential and a panmictic species, the lack of isolation by distance may be a result of range expansion following the last glacial maximum.
Committee in charge: Patrick Phillips, Chairperson, Biology; Alan Shanks, Advisor, Biology; Craig Young, Member, Biology; Richard Emlet, Member, Biology; Jon Erlandson, Member, Anthropology; Gregory Retallack, Outside Member, Geological Sciences
26
O'Donnell, M. A. (Margaret Anne). "The ecology and early life history of the intertidal tubeworm Galeolaria caespitosa." Phd thesis, Faculty of Arts, 1986. http://hdl.handle.net/2123/12045.
Full text
27
Lam, Kwok Cheong. "Aspects of the ecology of Musculista senhousia (Benson in Cantor, 1842) and its biological role on intertidal beaches in Hong Kong." HKBU Institutional Repository, 2000. http://repository.hkbu.edu.hk/etd_ra/276.
Full text
28
Smith, Kate. "Biodiversity of the invertebrate communities associated with intertidal mussel beds on rocky shores." Thesis, Bangor University, 2001. https://research.bangor.ac.uk/portal/en/theses/biodiversity-of-the-invertebrate-communities-associated-with-intertidal-mussel-beds-on-rocky-shores(48485c79-2e4c-48d7-93c9-60b67d78e30f).html.
Full textAbstract:
The invertebrate communities associated with intertidal mytilid mussel species were investigated on a variety of wave-exposed rocky shores around the coasts of the British Isles, Irish Republic (Mytilus edulis) and Chile, South America (Perumytilus purpuratus). A total of 192 different taxa were identified in Mytilus edulis beds at various rocky shore sites in the British Isles and Irish Republic, while 35 taxa were identified to higher taxonomic levels in Perumytilus purpuratus beds in Chile, South America. Significant small-scale spatial variations in community structure were observed at two locations in Wales, while significant large-scale spatial variations in community structure were observed within mussel beds both in the British Isles and Irish Republic and in Chile. Additionally, the communities associated with M. edulis and P. purpuratus differed significantly, when compared at the same taxonomic levels. The structure of the invertebrate communities associated with M. edulis populations showed significant intra-annual variation, while those associated with M. edulis and P. putpuratus displayed significant inter-annual variation. The spatial and temporal variation observed in the structure of the invertebrate communities associated with intertidal mussel beds were deemed to be the result of a variety of natural processes, along with stochastic events. Variation in measured environmental factors in the mussel beds did not fully account for the observed variation in community structure, although some factors, such as mussel density were shown to have some structuring effect. It is concluded that the structure of the invertebrate communities associated with intertidal mussel on rocky shores are highly variable, both spatially and temporally. However, a small subset of taxa often display the same multivariate patterns as the entire data set; a phenomenon which could be utilised in any monitoring or impact studies involving mussel communities.
29
Dreyer, Nicolaas Burger. "Within- and between-beach variation in intertidal macrofaunal communities inhabiting two Transkei sandy beaches." Thesis, Nelson Mandela Metropolitan University, 2008. http://hdl.handle.net/10948/1070.
Full textAbstract:
Until recently most sandy beach studies have made use of snapshot samples but the validity of this approach has been widely questioned. In this study we attempt to resolve this issue by repeatedly sampling two beaches using a stratified random design. Three sampling sessions took place, each approximately six months apart. The three sites on the first beach were selected according to the type of beach (reflective, intermediate and dissipative) with each morphological type duplicated on the second beach. Many of the physical variables measured had significant differences between the sampling sessions but only a few were significantly different between the Sites. Very few of the individual physical variables had significant relationships with the sandy beach macrofaunal abundance and density. However, composite indices had a greater number of significant relationships with the macrofaunal abundance and density. Also very few significant relationships were seen between the species richness and the physical variables of the beaches studied. Effluent line crossing frequency was the only physical variable that could predict species richness but it was considered a weak predictor. Changes in the zonation patterns within and between beaches were also investigated. The highest concentration of taxa and individuals was found near the low-water mark with a gradual reduction of both towards the high-water mark. Some of the sandy beach community variables (abundance, density and species richness) showed significant difference between the sampling sessions but no significant differences were seen between the two beaches. The presence of three zones was noted using MDS plots and Cluster diagrams. However, using a SIMPER analyses, four zones with the possibility of a fifth was noted.
30
Dias, Itala Farias. "DistribuiÃÃo espaÃo-temporal e densidade populacional de Holothuria (Halodeima) Grisea (Holothuroidea: Aspidochirotida) na Praia de BitupitÃ, CearÃ, Nordeste do Brasil." Universidade Federal do CearÃ, 2012. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=8916.
Full textAbstract:
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel SuperiorA espÃcie Holothuria grisea, pertencente à FamÃlia Holothuriidae, apesar de ser comum na costa brasileira, ainda apresenta uma lacuna de conhecimento em relaÃÃo aos seus aspectos ecolÃgicos. O objetivo do presente trabalho foi verificar variaÃÃes temporais na abundÃncia, densidade e estrutura populacional de Holothuria grisea, bem como verificar seu padrÃo de distribuiÃÃo espacial. O local de estudo foi a Praia de BitupitÃ, localizada no municÃpio de Barroquinha - CearÃ, distante aproximadamente 420 km de Fortaleza. As coletas ocorreram no perÃodo de janeiro a dezembro de 2011, durante as marÃs diurnas de sizÃgias na zona entremarÃs de um recife de arenito da referida praia. A metodologia baseou-se em um transecto perpendicular à linha da praia com 160 metros de comprimento marcando-se seis pontos distantes entre si dez metros. Foi utilizado um quadrado de 4 m em cada ponto marcado. Os espÃcimes encontrados nestes quadrantes foram contados, medidos e pesados. Foram mensurados os parÃmetros abiÃticos salinidade, temperatura, pH e oxigÃnio dissolvido, com auxÃlio de um refratÃmetro, termÃmetro, pHmetro e oxÃmetro, respectivamente. Foi realizada anÃlise granulomÃtrica do sedimento no perÃodo chuvoso e de estiagem. O padrÃo de distribuiÃÃo espacial encontrado foi do tipo agregado corroborando com a literatura existente. Observou-se um total de 620 indivÃduos de H. grisea no perÃodo estudado. A pluviosidade influenciou na abundÃncia de H. grisea, uma vez que no perÃodo chuvoso obteve-se maior abundÃncia comparada ao perÃodo de estiagem. Houve correlaÃÃo positiva entre a pluviosidade e abundÃncia (r= 0,514). A mÃdia de densidade anual foi de 0.54  0.14 ind/mÂ. NÃo houve diferenÃa entre as mÃdias de densidades ao longo dos meses, nem entre os dados agrupados do perÃodo chuvoso e de estiagem; estes fatos podem ser explicados pelo padrÃo de distribuiÃÃo agregada da populaÃÃo. O tamanho mÃdio observado dos indivÃduos de H. grisea foi 12,89  2,42 cm, com uma distribuiÃÃo de frequÃncia unimodal. O peso mÃdio observado foi 90,28  30,29 g apresentando uma distribuiÃÃo de frequÃncia unimodal. Houve correlaÃÃo positiva entre peso e tamanho dos indivÃduos da populaÃÃo O presente estudo, contribuiu para novos conhecimentos em ecologia dos Holothuroidea presentes em Ãguas tropicais.
The species Holothuria grisea, belonging to the Family Holothuriidae, despite being common in Brazilian coast, still has a big gap in relation to its ecological aspects. The aim of this study was to assess temporal variations in abundance, density and population structure of Holothuria grisea, as well as verify their spatial distribution pattern. The study site was the Bitupità Beach, located in the municipality of Barroquinha - CearÃ, distant about 420 km from Fortaleza. The samples were collected during diurnal spring tides in the intertidal zone on a rock shore of Bitupità Beach during January to December 2011. The methodology was based on a transect perpendicular to the beach with 160 meters long by scoring six points among ten meters. We used a square of 4 m at each marked point and the Holothuria grisea found in this square were counted, measured and weighed. The abiotic parameters were measured such as salinity, temperature, pH and dissolved oxygen. Analyses of sediment were performance in the rainy season and the dry season of 2011. The spatial distribution pattern found for Holothuria grisea was aggregate. We observed a total of 620 individuals of H. grisea during the study period. Rainfall influenced the abundance of H. grisea, since the rainy season yielded greater abundance compared to the dry season. We found a positive correlation between rainfall and abundance (r= 0.514). The average annual density was 0.54  0.14 ind / mÂ. There was no difference between the mean densities over months or between the wet and dry seasons, this fact can be explained by the spatial distribution of the aggregate population. The average size observed was 12.89 cm  2.42 cm frequency unimodal distribution. The average weight was observed  30.29 g 90.28 g showing a frequency distribution unimodal. There was a positive correlation between weight and size of the population. This study has contributed to new knowledge in Holothuroidea ecology in tropical waters.
31
Forster, Simon John. "Aspects of the ecology of free-living nematode assemblages in a temperate intertidal mudflat." Thesis, Queen Mary, University of London, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.322118.
Full text
32
Warburton, Karen M. "Effects of a wastewater outfall in a rocky intertidal community /." California : Humboldt State University, 2005. http://hdl.handle.net/2148/23.
Full text
33
Cushnie, Graeme C. "The patchiness of some intertidal communities on Manx rocky shores." Thesis, University of Liverpool, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.263847.
Full textAbstract:
This study investigated the factors that maintain the patchiness of various rocky shore communities, particularly the roles of physical disturbance and biological interactions. Three communities were studied: a rnidshore red algal turf dominated by Laurencia pinnatifida, a Cladophora rupestris turf that dominated an area of the lowshore'and a fucoidbarnacle mosaic in the rnidshore that was interspersed by limpets. The study of the Laurencia turf showed it to be extremely stable once established and that its primary mode of recolonisation was by vegetative encroachment. Because of its slow growth L. pinnatifida did not recolonise and dominate any gaps that occurred in the turf within the timescale of this study. The Cladophora rupestris community was not only extremely stable, but was also persistent. Cladophora rupestris returned as the dominant alga to disturbed areas irrespective of the size, shape or season of the disturbance and this may have been because of processes involving the inhibition of other species such as Fucus serratus by early successional species which Cladophora rupestris could tolerate. Repeated disturbance events may have broken such inhibitions, enabling other species to colonise the substratum to higher levels of abundance than would normally have occurred. In the Laurencia and Cladophora turfs few limpets were required to maintain gaps in the turf, but these areas were rapidly recolonised by algae if all limpets were removed. The gaps in the Cladophora turf became dominated by Cladophora rupestris, however, in the Laurencia turf Laurencia pinnatifida did not recolonise the gaps that had been kept clear by limpet grazing. In the midshore fucoid, barnacle and limpet community the limpet densities had to be reduced to half of the natural levels to permit the colonisation of barnacle matrix by algae. The cover by FUCllS vesiculosus was .inversely related to the density of limpets, with the largest values being obtained in areas that were devoid of limpets. The effect of modifying the environmental conditions, by shading and watering the barnacle matrix, on the establishment of Fucus vesiculosus germlings was also studied. This showed that more shade tended to result in a greater number of fucoid escapes, possibly because of insolation stress and photoinhibition of the germlings on the unshaded substratum. The persistence offucoid patches was found to be affected by both the size of the area and the duration for which it was protected from limpet grazing. From the studies I carried out it is apparent that there were several forms of patchiness on the moderately exposed rocky shores on the south coast of the Isle of Man. These result from the vertical environmental stress gradient and interactions between plants and animals and in each case the exact sequence of events that followed a disturbance, depended on the species involved.
34
Allen, Christopher John. "Ecology of the intertidal crab Dotilla intermedia from tsunami-impacted beaches in Thailand." Thesis, University of Southampton, 2010. https://eprints.soton.ac.uk/169031/.
Full textAbstract:
Crabs of the genus Dotilla are ecologically important members of intertidal sandy shore communities. Exposed sandy shores represent one of the main habitat types along the coast of the Laem Son National Park in Thailand, and Dotilla sp. is the dominant macrofaunal species on these beaches, occurring in immense numbers. Despite their importance as a key member of the faunal community on these beaches, little is known about the ecology of Dotilla crabs in the Laem Son. Taxonomic investigations identified the Dotilla crabs present on the exposed oceanic beaches in the Laem Son to be D. intermedia. This represents the first time that D. intermedia has been recorded from Thailand. Dotilla intermedia inhabits a very well defined zone on the sandy beaches, and the factors underlying these zonation patterns were examined. The gradient of the beach was correlated to the height at which the boundaries of the Dotilla zone occurred, with physical factors associated with the beach gradient driving the distribution of D. intermedia on the beach. The upper limit of the Dotilla zone was controlled by the total water content of the sediment, with D. intermedia absent from areas with less than 15% total water content. Tidal influences defined the lower boundary of the Dotilla zone, with crabs requiring an area with a minimum exposure time between tidal immersions of 4-5 hours to feed on the sediment. Within the Dotilla zone, size segregation was observed; larger crabs occurred higher on the shore, and small crabs lower down. The sandy shores of the Laem Son were heavily impacted by the tsunami of 26th December 2004, which effectively destroyed the populations of D. intermedia on the beaches. However, by April 2005 D. intermedia was present again on the beaches. A temporal population genetic study was undertaken to investigate the impact of extinction and recolonisation on the genetic variation of a population. Genetic variation in mtDNA markers was found to decrease over time, matching the predictions of mathematical models concerning the effect of bottlenecking events on genetic diversity within populations. The impact of the tsunami on D. intermedia is discussed further in light of the ecological and molecular data produced in this thesis.
35
Hill, Jaclyn Marie. "A stable isotope approach to trophic ecology resolving food webs in intertidal ecosystems." Thesis, Rhodes University, 2008. http://hdl.handle.net/10962/d1005459.
Full textAbstract:
There are broad differences in regional oceanography and primary production around the South African coast, which we might expect to give rise to major differences in trophic pathways. δ⁻¹³C and δ⁻¹⁵N isotopic ratios of suspended particulate matter (SPM), mussels, various intertidal consumers and common macroalgae along the South African coastline were explored using stable isotope analysis to investigate biogeographic and temporal variability of isotopic signatures of marine intertidal consumers and their food sources around the coast of South Africa, with a focus on evaluating the dependence of intertidal mussels on phytoplankton and macroalgal-derived organic carbon. Isotopic equilibration rates of four mussel tissues were determined through laboratory feeding experiments, which established that adductor tissue had the slowest isotopic turnover rate, and was subsequently used as an indication of overall mussel diet. Biogeographic, temporal and nearshore/offshore trends of isotopic ratios of SPM were investigated along 10km transects perpendicular to the coast and SPM exhibited overall trends of carbon depletion when moving from west to east along the coastline and from nearshore to offshore water, in both cases suggesting a shift from macrophyte detritus to a phytoplankton signature. δ⁻¹³C signatures of SPM also revealed temporal and biogeographic variation that had strong ties to local oceanography, being closely correlated to regional hydrographic features and tidal influences. Mixing models indicated filter feeders demonstrated over 50% dependence on nearshore SPM for organic carbon and it was possible to categorize them into geographic groups based on their carbon and nitrogen signatures, suggesting biogeographic shifts in resources. Biogeographic shifts in diet were also seen in some grazers. Difficulties in relating macroalgae to mussel diet led to investigations into the isotopic changes associated with macroalgal decomposition. Variation in photosynthetic fractionation, leaching and microbial mineralization are believed to have resulted from species-specific patterns of degradation. Although the strong links between carbon signatures and local oceanography indicate that stable isotope analysis is a powerful tool for the study of water mixing and coastal hydrography in relation to food-web analyses, substantial variation in fractionation of primary consumers, along with different periods of time integration between consumers and their food sources must be considered in future studies, to resolve trophic links in marine food webs successfully.
36
Jeffrey, Carolyn Jean. "Ecology of the rocky shore intertidal barnacle Chamaesipho tasmanica in New South Wales." Thesis, University of Sydney, 1997. http://hdl.handle.net/2123/3765.
Full text
37
Hurley, Tania Dianne. "Sediment-algal interactions on intertidal rocky reefs." Thesis, University of Canterbury. Biological Science, 2009. http://hdl.handle.net/10092/3197.
Full textAbstract:
Macroalgae are a dominant feature of many rocky intertidal habitats worldwide. An understanding of the processes affecting their growth and survival, especially at early life history stages, is therefore important to an understanding of the structure of rocky intertidal communities. This thesis examines the role that the sediment environment has on habitat-dominating fucoid algae and intertidal community structure. Measurements of sediment flux showed considerable spatial and seasonal variation, while the benthic sediment environment remained relatively stable. Experimental disturbances over 13 months, showed two distinct effects. First, direct effects of sedimentation favoured ephemeral algae and also those with tough thalli. Secondary to this was an alteration of species interactions due to the shifts in community composition. The effect sedimentation has on habitat dominating fucoid algae was also examined with laboratory experiments and outplants of cultured algae. The presence of sediment had a negative effect on the ability of Cystophora torulosa and Hormosira banksii zygotes to attach to the substratum, with even sparse coverings of sediment preventing at least 37% of zygotes attaching to the substratum, and almost a complete recruitment failure with dense coverings of both sand and silt. Sediment and disturbance of turfing communities also influenced early post-settlement survival especially of C. torulosa. Manipulations of the sediment load, nutrient levels and grazer abundance showed the resilience of rocky intertidal communities to the predicted increase in nutrient leaves in coastal waters due to increases anthropogenic intrusion. Most research into the effects of sedimentation have been observational studies and much of the experimental work has been carried out subtidally. My experiments have extended research into the intertidal zone, finding that if sedimentation increases as predicted there will be a consequential loss of habitat dominating fucoid algae and its replacement with sediment tolerant species
38
Thomas, N. S. "Aspects of the ecology of the microinvertebrates in the intertidal soft sediments of Chichester harbour." Thesis, University of Portsmouth, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.376685.
Full text
39
Miller, Luke Paul. "Life on the edge : morphological and behavioral adaptations for survival on wave-swept shores /." May be available electronically:, 2008. http://proquest.umi.com/login?COPT=REJTPTU1MTUmSU5UPTAmVkVSPTI=&clientId=12498.
Full text
40
Harley, Christopher David Grant. "Environmental modification of biological interactions : a comparison across scales /." Thesis, Connect to this title online; UW restricted, 2001. http://hdl.handle.net/1773/5271.
Full text
41
Bryson, 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 text
42
Nakamachi, Takeru. "Life history and reproductive ecology of an intertidal isopod Dynoides dentisinus (Crustacea: Peracarida: Isopoda)." Kyoto University, 2019. http://hdl.handle.net/2433/242643.
Full text
43
Saunders, James Edward. "Measuring and understanding biogenic influences upon cohesive sediment stability in intertidal systems." Thesis, St Andrews, 2008. http://hdl.handle.net/10023/868.
Full text
44
Dias, Itala Farias. "Distribuição espaço-temporal e densidade populacional de Holothuria (Halodeima) Grisea (Holothuroidea: Aspidochirotida) na Praia de Bitupitá, Ceará, Nordeste do Brasil." reponame:Repositório Institucional da UFC, 2012. http://www.repositorio.ufc.br/handle/riufc/18355.
Full textAbstract:
DIAS, Itala Farias. Distribuição espaço-temporal e densidade populacional de Holothuria (Halodeima) Grisea (Holothuroidea: Aspidochirotida) na Praia de Bitupitá, Ceará, Nordeste do Brasil. 2012. 69 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Centro de Ciências Agrárias, Departamento de Engenharia de Pesca, Fortaleza-CE, 2012Submitted by Nádja Goes (nmoraissoares@gmail.com) on 2016-07-15T12:37:46Z No. of bitstreams: 1 2012_dis_ifdias.pdf: 2211610 bytes, checksum: d490eaec99d0bb2f03f1c40e3889bdb5 (MD5)
Approved for entry into archive by Nádja Goes (nmoraissoares@gmail.com) on 2016-07-15T12:38:10Z (GMT) No. of bitstreams: 1 2012_dis_ifdias.pdf: 2211610 bytes, checksum: d490eaec99d0bb2f03f1c40e3889bdb5 (MD5)
Made available in DSpace on 2016-07-15T12:38:10Z (GMT). No. of bitstreams: 1 2012_dis_ifdias.pdf: 2211610 bytes, checksum: d490eaec99d0bb2f03f1c40e3889bdb5 (MD5) Previous issue date: 2012
The species Holothuria grisea, belonging to the Family Holothuriidae, despite being common in Brazilian coast, still has a big gap in relation to its ecological aspects. The aim of this study was to assess temporal variations in abundance, density and population structure of Holothuria grisea, as well as verify their spatial distribution pattern. The study site was the Bitupitá Beach, located in the municipality of Barroquinha - Ceará, distant about 420 km from Fortaleza. The samples were collected during diurnal spring tides in the intertidal zone on a rock shore of Bitupitá Beach during January to December 2011. The methodology was based on a transect perpendicular to the beach with 160 meters long by scoring six points among ten meters. We used a square of 4 m² at each marked point and the Holothuria grisea found in this square were counted, measured and weighed. The abiotic parameters were measured such as salinity, temperature, pH and dissolved oxygen. Analyses of sediment were performance in the rainy season and the dry season of 2011. The spatial distribution pattern found for Holothuria grisea was aggregate. We observed a total of 620 individuals of H. grisea during the study period. Rainfall influenced the abundance of H. grisea, since the rainy season yielded greater abundance compared to the dry season. We found a positive correlation between rainfall and abundance (r= 0.514). The average annual density was 0.54 ± 0.14 ind / m². There was no difference between the mean densities over months or between the wet and dry seasons, this fact can be explained by the spatial distribution of the aggregate population. The average size observed was 12.89 cm ± 2.42 cm frequency unimodal distribution. The average weight was observed ± 30.29 g 90.28 g showing a frequency distribution unimodal. There was a positive correlation between weight and size of the population. This study has contributed to new knowledge in Holothuroidea ecology in tropical waters.
A espécie Holothuria grisea, pertencente à Família Holothuriidae, apesar de ser comum na costa brasileira, ainda apresenta uma lacuna de conhecimento em relação aos seus aspectos ecológicos. O objetivo do presente trabalho foi verificar variações temporais na abundância, densidade e estrutura populacional de Holothuria grisea, bem como verificar seu padrão de distribuição espacial. O local de estudo foi a Praia de Bitupitá, localizada no município de Barroquinha - Ceará, distante aproximadamente 420 km de Fortaleza. As coletas ocorreram no período de janeiro a dezembro de 2011, durante as marés diurnas de sizígias na zona entremarés de um recife de arenito da referida praia. A metodologia baseou-se em um transecto perpendicular à linha da praia com 160 metros de comprimento marcando-se seis pontos distantes entre si dez metros. Foi utilizado um quadrado de 4 m² em cada ponto marcado. Os espécimes encontrados nestes quadrantes foram contados, medidos e pesados. Foram mensurados os parâmetros abióticos salinidade, temperatura, pH e oxigênio dissolvido, com auxílio de um refratômetro, termômetro, pHmetro e oxímetro, respectivamente. Foi realizada análise granulométrica do sedimento no período chuvoso e de estiagem. O padrão de distribuição espacial encontrado foi do tipo agregado corroborando com a literatura existente. Observou-se um total de 620 indivíduos de H. grisea no período estudado. A pluviosidade influenciou na abundância de H. grisea, uma vez que no período chuvoso obteve-se maior abundância comparada ao período de estiagem. Houve correlação positiva entre a pluviosidade e abundância (r= 0,514). A média de densidade anual foi de 0.54 ± 0.14 ind/m². Não houve diferença entre as médias de densidades ao longo dos meses, nem entre os dados agrupados do período chuvoso e de estiagem; estes fatos podem ser explicados pelo padrão de distribuição agregada da população. O tamanho médio observado dos indivíduos de H. grisea foi 12,89 ± 2,42 cm, com uma distribuição de frequência unimodal. O peso médio observado foi 90,28 ± 30,29 g apresentando uma distribuição de frequência unimodal. Houve correlação positiva entre peso e tamanho dos indivíduos da população O presente estudo, contribuiu para novos conhecimentos em ecologia dos Holothuroidea presentes em águas tropicais.
45
Cheung, Pui-shan Catherine. "An intertidal survey of Cape d'Aguilar, Hong Kong with special reference to the ecology of high-zoned rock pools /." [Hong Kong] : University of Hong Kong, 1991. http://sunzi.lib.hku.hk/hkuto/record.jsp?B13028352.
Full text
46
Jessop, Rosalind Elinor, and mikewood@deakin edu au. "The ecology of fish inhabiting the inter-tidal zone of Swan Bay, Victoria, Australia." Deakin University. School of Sciences, 1988. http://tux.lib.deakin.edu.au./adt-VDU/public/adt-VDU20050826.121023.
Full textAbstract:
Swan Bay is a shallow marine embayment of Port Phillip Bay, just north of Queenscliff, Victoria. It has been part of the Harold Holt Marine Reserves since 1977 and is a seagrass habitat. This study investigated the species of fish present in the inter-tidal zone of Swan Bay, collected information on their ecology, investigated the importance of Swan Bay compared to Port Phillip Bay as a nursery and/or breeding area and compared these results with those of similar seagrsss habitats.
Field work was carried out monthly over a two year period, from April 1981 to April 1983, using beach seine nets at Swan Bay and Portarlington.
Forty four species of fish were identified from Swan Bay and nineteen from Portarlington. Fish were most abundant during the summer and autumn months when seagrass growth was at a maximum and least abundant during winter due to the absence of seasonal residents and decreased numbers of permanent residents.
Swan Bay was found to be an important nursery ground for two commercially-caught species: the Yellow-eye Mullet and the King George Whiting. Juvenile Yellow-eye Mullet were more numerous in Swan Bay than at Portarlington. Smell juvenile King George Whiting were more abundant at Portarlington than in Swan Bay where older juveniles were more numerous.
The fish fauna of Swan Bay was found to be similar to western Port but the abundance of species varied. Atherinosome microstoma was the dominant species in terms of abundance and biomass. Diet was found to be different from that reported by Robertson (1979) at Western Port due to the different range of prey items.
47
Gouhier, Tarik Claude. "The role of disturbance cycles in marine mussel metapopulations /." Thesis, McGill University, 2005. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=98713.
Full textAbstract:
In marine environments, the open system (OS) theory, whereby populations are assumed to be well connected through large-scale dispersal, is currently being challenged by studies demonstrating limited dispersal. Using a novel metapopulation framework featuring nonequilibrium within-site disturbance cycles and limited dispersal, I investigate the large-scale response of marine mussel populations to changes in oceanographic productivity. By altering the fecundity parameter, I am able to shift from open to dynamically-coupled systems (DCS), thereby generating predictions that can be used to test the connectivity of marine populations. Within-site disturbance cycles scale-up and drive regional dynamics in both OS and DCS. Fast disturbance cycles induce synchronized oscillations that promote regional extinction risk in response to changes in oceanographic productivity for DCS but not OS. Slow disturbance cycles maintain spatial variability and temporal stability in both OS and DCS. These predictions can be used to test the applicability of OS theories to natural coastal ecosystems.
48
Potouroglou, Maria. "Assessing the role of intertidal seagrasses as coastal carbon sinks in Scotland." Thesis, Edinburgh Napier University, 2017. http://researchrepository.napier.ac.uk/Output/975386.
Full textAbstract:
Seagrasses are marine foundation species that form ecologically important habitats in coastal areas around the world. They provide a range of ecosystem services, including coastal protection and the recently recognised large contribution to global carbon sequestration and storage. To date, the majority of published studies on the aforementioned ecosystem services is limited to specific geographic regions and seagrass species. This PhD study attempted to explore and provide the first evidence, to the best of our knowledge, on the role of Scottishseagrasses as carbon sinks and sediment stabilisers. In 2013, shoot dynamics of Zostera noltii plots were monitored biweekly and seasonally in the Forth estuary and digital images of the surveyed plots were taken for the development of a remote sensing technique which would accurately estimate the vegetation cover. In 2014, sediment samples from vegetated and unvegetated plots within beds of Z. marina and Z. noltii were collected from all the major estuaries along the east coast of Scotland, from the Firth of Forth in the south to Dornoch Firth in the north. Samples were analysed for organic matter, organic carbon, radionuclides 210Pb, 137Cs and 241Am, and δ13C in order to determine the organic matter and organic carbon density, longevity and sources of carbon respectively. To explore the role of seagrass in sediment deposition and stability, surface elevation was measured monthly in seagrass plots and bare sediment in the Forth estuary over two years. The results and main mechanisms underlying these findings are reported and discussed in detail in each chapter. In short, the proposed method based on digital images provided estimates of seagrass coverage that are more accurate than observers' estimates, with some constraints when macroalge and/or extreme light are present. Intertidal seagrass meadows in Scotland showed significantly enhanced carbon storage compared with bare sediment. Seagrass plots contained variable quantities of carbon in their sediments with species composition having a significant effect on carbon stocks, whereas depth and seagrass abundance had no effect on carbon stores. Despite their small above-ground biomass Scottish seagrass plots had a strong influence on sediment deposition and prevented erosion. Further research is needed to understand what factors drive large carbon sequestration and storage at some sites, thus contributing policy-relevant information on the prediction of the seagrass carbon hot-spots. Also, long-term datasets on surface elevation change are important in order to understand the effect of all the processes involved on sediment deposition in seagrass beds.
49
Appadoo, Chandani. "Some aspects of the biogeography and ecology of intertidal and shallow subtidal marine gammaridean amphipods of Mauritius (Indian Ocean)." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape16/PQDD_0001/MQ34159.pdf.
Full text
50
Sbizera, Martinez Aline. "Reevaluating the dynamics of intertidal rocky shores: The foraging and behavioural ecology of an understudied grazer and its effects on benthic assemblages." Thesis, The University of Sydney, 2016. http://hdl.handle.net/2123/15485.
Full textAbstract:
The strongest grazing effect among all marine benthic systems is on intertidal rocky shores. Among intertidal grazers, limpets are well-known structuring agents altering the distribution of rocky shore assemblages. Globally, there are other abundant herbivores whose ecological importance in the dynamics of rocky shores is poorly studied as is the case for herbivorous starfish. Parvulastra exigua is a small starfish that occurs at great densities in rock pools on intertidal shores. This research aimed to understand the behavioural ecology of P. exigua by investigating the feeding and foraging habits of the starfish, competitive interactions between P. exigua and limpets, and the consequent effects on algal assemblages. Parvulastra exigua showed a narrow diet breadth with selection for microalgal food. This species fed during all periods of the tidal cycle. During immersion, the starfish foraged within and around rock pools and only foraged in pools whilst the tide was out. The starfish foraged near their rock pools, potentially creating a halo effect due to localized grazing. Rock pool fidelity in P. exigua varied among locations suggesting that the impact of this starfish on algal assemblages might be contingent on the availability of refugia at low tide and that the extent of the halo effect by P. exigua will vary from place to place. Parvulastra exigua revealed to be an equal competitor to a key limpet on the shore and the starfish was as efficient in controlling macroalgal growth as the limpet, with the strongest effect inside rock pools. These findings demonstrate that P. exigua is an important grazer in intertidal rocky shores. Herbivorous starfish occur on other rocky shores around the world and in sand flats, seagrass and kelp forests. Thus, future work is relevant to examine the effects of starfish herbivory on other shores and ecosystems.