Rozprawy doktorskie: „Mangrove habitats”

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Yerman, Michelle Nerida. "Temperate urban mangrove forests : their ecological linkages with adjacent habitats /". View thesis, 2003. http://library.uws.edu.au/adt-NUWS/public/adt-NUWS20060517.092914/index.html.

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Thesis (M. Sc.) (Hons) -- University of Western Sydney, 2003.
"Submitted in accordance with guidelines for the Degree of Master of Science (Hons), College of Science, Technology and the Environment, University of Western Sydney, Hawkesbury, Richmond NSW, Australia, March 2003." Includes bibliography : leaves 229 - 254, and appendices.

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Yerman, Michelle N., University of Western Sydney, of Science Technology and Environment College i School of Natural Sciences. "Temperate urban mangrove forests : their ecological linkages with adjacent habitats". THESIS_CSTE_NSC_Yerman_M.xml, 2003. http://handle.uws.edu.au:8081/1959.7/652.

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Estuarine habitats along the temperate south-eastern shores of Australia are generally made up of salt marsh, mangrove forests and seagrass beds. In urban areas these habitats have been progressively fragmented as a result of population increase and industrial expansion. Salt marshes in particular have been vulnerable to urban expansion and reclamation because of their close proximity to densely populated areas, while mangrove forests have been less often reclaimed because of frequent tidal inundation. The effect of reclamation of salt marshes on the biotic assemblages and functioning of mangrove forests with an adjacent salt marsh, park or bund wall was examined at nine separate locations on the Parramatta River, Sydney NSW. A mensurative approach was used to describe the patterns of distribution and abundance of macro fauna at several temporal and spatial scales. The implications for management are that salt marshes are an integral part of estuaries, and smaller patches of salt marsh are just as important as larger patches in maintaining the diversity of faunal assemblages and ecosystem functioning in mangrove forests in urban areas
Master of Science (Hons)

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Manson, Fiona Jane. "Mangroves and fisheries: are there links between coastal habitats and fisheries production? /". [St. Lucia, Qld.], 2005. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe18551.pdf.

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Goebel, Patrick C. "Distribution, Abundance and Movement of Fish among Seagrass and Mangrove Habitats in Biscayne Bay". NSUWorks, 2016. http://nsuworks.nova.edu/occ_stuetd/403.

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Inshore tropical and subtropical estuaries harbor a relatively high abundance and diversity of organisms. Specifically within estuaries, mangrove and seagrass habitats provide shelter and food for a plethora of organisms, through some or all their life histories. Given the biological connection between offshore coral reefs and coastal estuaries, there is a critical need to understand the underlying processes that determine distribution and abundance patterns within mangrove-seagrass habitats. The predatory fish assemblage within the mangrove and seagrass beds of Biscayne Bay, Florida (USA), was examined over 24-hr. time periods along a distance and habitat gradient from the mangrove edge and nearshore environment (0–300 m) to farshore (301–700 m) seagrass beds. This thesis also investigated the occurrence, distribution and timing of reef fish movement between offshore coral reef habitat and inshore seagrass beds over 24-hr periods. Results indicate that fish predators differed over both the sampling period and with distance from mangrove edge. The results also demonstrated reef fishes move into Biscayne Bay at dusk and exit at dawn by utilizing Broad Creek Channel as a passageway. This work supports the idea of diel migration of selected reef fishes to inshore seagrass beds and highlights the importance of connective channels between habitats. The results suggest that the degradation or loss of seagrass habitat could differentially impact the life-history stages of reef fish species.

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Wilton, Kylee Margaret, i res cand@acu edu au. "Coastal Wetland Habitat Dynamics in Selected New South Wales Estuaries". Australian Catholic University. School of Arts and Sciences, 2002. http://dlibrary.acu.edu.au/digitaltheses/public/adt-acuvp29.29082005.

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Intertidal wetland habitats in southeastern Australia have changed significantly during the past sixty years. Mangrove habitats have expanded both seawards and landwards, the latter being at the expense of saltmarsh habitats. This relatively common phenomenon is generally suggested to be an outcome of sea-level rise. Several factors potentially responsible for this change are examined, including changes in mean sealevel during the past 50 to 100 years, changes in climate, population growth, catchment landuse, and estuary type. A protocol for mapping estuarine habitats was developed and implemented, incorporating the application of geographic information systems. Spatial and temporal coastal wetland habitat changes at nine sites along the New South Wales coast are illustrated. These habitat dynamics were shown to not correlate between sites. The results demonstrate that sea-level rise in this region cannot solely account for the extent of change during the past sixty years. With the exception of one site (Careel Bay), there have been no correlations between contemporary mean sea-level rise and mangrove incursion of the saltmarsh habitats at the study sites, or with rainfall patterns, at the scale of observation in this study, which was largely decadal. The only correlations determined during this study have been between population growth and coastal wetland habitat dynamics in some sites. In spite of saltmarsh habitat loss being a regional phenomenon, local factors appear to have a profound bearing on the rates of change. Neither contemporary mean sea-level rise, rainfall patterns, estuary type, catchment landuse, catchment natural cover nor population pressure can account solely for the patterns in the spatial and temporal dynamics of the coastal wetlands of New South Wales. It seems apparent that regional factors create preconditions favourable for mangrove incursion, but that localised conditions have been responsible for the extent of these incursions from site to site. That is, despite higher sea-level and greater rainfall, the extent of change has been determined by the unique characteristics of each site. The results have important implications for current estuary management practices in the state of New South Wales. The lack of spatial and temporal trends in coastal wetland habitat dynamics point to the need for management to be conducted on a localised, rather than regional scale. Additionally, anthropogenic influences must be carefully managed, since the extent of mangrove habitat expansion into saltmarsh areas is unlikely to be a natural occurrence.

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Santos, Rolando O. "Linkage Between Mangrove Fish Community and Nearshore Benthic Habitats in Biscayne Bay, Florida, USA: A Seascape Approach". NSUWorks, 2010. http://nsuworks.nova.edu/occ_stuetd/214.

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The role of mangroves as essential fish habitat has been a focus of extensive research. However, recent evidence has shown that this role should not be evaluated in isolation from surrounding habitats such as seagrass beds and hard-bottom communities. For example, submerged aquatic vegetation (SAV) communities provide potential sources of food and shelter for fish species that may reside in the mangroves, but may also undergo ontogenetic migrations and daily home-range movements into neighboring habitats. The connectivity between the mangrove fish community and the surrounding seascape may be influenced by the level of patchiness, fragmentation, and spatial heterogeneity of adjacent SAV habitats (i.e., SAV seascape structure). The spatial patterns and heterogeneity of SAV seascape structures are driven by internal and external regulatory mechanisms operating at different spatial and temporal scales. In addition, it is likely that many fish species inhabiting the mangrove zones have different home ranges, and foraging and migratory patterns; therefore, different mangrove fish species may respond to seascape heterogeneity at different scales. There are few studies that have assessed the influence and connectivity of benthic habitats adjacent to mangroves for estuarine fish populations at multiple scales. The present research used an exploratory seascape approach in Biscayne Bay (Florida, USA) to evaluate patterns in the patch composition and configuration of SAV communities, and to examine relationships between seascape structural metrics and the abundance, diversity, and distribution of fishes that utilize the adjacent mangrove shoreline as nursery and/or adult habitat. This seascape approach consisted of: a) the multi-scale characterization of the SAV distribution across the seascape with metrics developed in Landscape Ecology, Geographic Information Systems and Remote Sensing; b) multivariate analyses to identify groups with significantly distinct SAV seascape structures within the most heterogeneous scale, and identify possible mechanisms driving the observed SAV seascape structures; and c) an assessment of the mangrove fish community responses to SAV seascape structures. By applying a set of multivariate analyses (e.g., ANOSIM, MDS plots, hierarchical clustering), the buffer within 200 m from shore was identified as the scale with the highest structural heterogeneity. At this scale, two major SAV seascape structures (i.e., areas with similar SAV spatial arrangement and composition) were identified: a fragmented SAV seascape (FSS) structure and a continuous SAV seascape (CSS) structure. Areas with CSS were characterized by large, uniform SAV patches. In contrast, areas with FSS were characterized by a higher density of smaller, more complex SAV patches. Furthermore, the areas with CSS and FSS structures clustered in zones of the bay with distinct salinity properties. The areas with CSS structures were mostly located in zones characterized by high and stable salinity. However, the areas with FSS concentrated in zones that are influenced by freshwater discharges from canals and with low and variable salinity. The responses of fish diversity metrics were not constrained to the scale at which the greatest spatial heterogeneity of SAV seascape structures was observed (i.e., the seascape composition and configuration within 200 m from shore), but was related to SAV seascape characteristics across different scales. The majority of the variability of the fish diversity metrics in the mangrove shoreline was explained by SAV seascape structures within the smaller scales (i.e., 100-400 m from shore), and SAV seascape structures that represented the level of fragmentation and/or the percent of suitable habitat. Different conceptual models were proposed to illustrate and understand the ecological dynamics behind the relationship between the diversity of the mangrove fish community and the structure of the adjacent SAV seascape. In general, the diversity and abundance of fishes is influenced by the type and level of fragmentation of the SAV seascape, which, in turn, influence the proportion of the seascape used for foraging and refuge by fish. In conclusion, this research quantified how the release of large pulses of freshwater into near-shore habitats of coastal lagoons can influence the seascape structure of SAV communities. Namely, freshwater inputs produce fragmentation in otherwise fairly homogeneous SAV meadows. The outcome of this research highlights the importance of seascape characteristics as indicators of ecosystem-level modifications and alterations affecting the spatial distribution, assemblage, and diversity of marine nearshore habitats in coastal regions heavily influenced by human activities. In addition, the results illustrated the cascading effects and synergistic influences of near-shore habitat spatial assemblages on the composition and diversity of estuarine fish communities. Lastly, and very importantly, the relationships established in this project provide quantitative and qualitative information on patterns of species-habitat associations needed for the improved synergistic management and protection of coastal habitats and fisheries resources.

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Guest, Michaela A., i n/a. "Movement and Assimilation of Carbon by Estuarine Invertebrates". Griffith University. School of Environmental and Applied Science, 2004. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20061024.110617.

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In estuarine and other aquatic systems, it is possible for water to transport locally produced carbon (food) across habitat boundaries, and provide nutrition for animals remote from the carbon source. In estuarine and marine systems, early work examining the movement of carbon from saltmarsh habitats in the USA suggested that carbon may move large distances from inshore to offshore environments. Upon closer examination, however, evidence did not support this paradigm of large-scale carbon movement, referred to as the outwelling hypothesis, in some estuaries. Physical characteristics of estuaries in which large-scale carbon movement did not occur, such as restricted access to the sea, were proposed as a possible explanation, and for these estuaries, movement of carbon among estuarine habitats was considered more likely. A mosaic of saltmarsh and mangrove habitats dominate the subtropical barrier estuary of southern Moreton Bay, Queensland, but there have been no studies that examine the movement of carbon among habitats within this system. Previous studies that examine the movement of carbon have mostly been done in saltmarshes in the northern hemisphere or in tropical mangrove systems. Different vegetation and tidal regimes in temperate marshes of the northern hemisphere preclude generalisations of carbon movement to tropical and subtropical systems. Our understanding of carbon movement in tropical systems may extend to subtropical waters, but the saltmarsh-mangrove mosaic in the subtropics distinguishes them from their tropical counterparts. The mosaic of saltmarsh and mangrove habitats among the barrier islands of southern Moreton Bay thus provide a unique opportunity to examine the small-scale movement of carbon among adjacent habitats in a subtropical system. Stable isotopes of carbon have been used successfully to trace the transfer of carbon from autotrophs to consumers at a range of spatial scales. This method is able to distinguish among carbon sources where autotrophs have different ratios of 13C/12C, and consumers take on the ratio of their food source. The success of stable isotopes in clarifying food web processes, however, depends on isotope ratios changing in predictable ways as elements are processed. As isotope ratios may be influenced by changes in productivity, and differences in nutrient source, they may vary across small and large spatial scales that may confound interpretation of food web processes. In this study I measured small and large-scale spatial variability of three estuarine autotrophs (the saltmarsh grass, Sporobolus virginicus, the seagrass Zostera capricorni and the algal community epiphytic on Z. capricorni) and showed the small-scale spatial variability to be negligible and insufficient to preclude the use of carbon and nitrogen isotopes in food web studies. Large-scale variability was more pronounced and may be useful for spatial correlation of food webs for more mobile species. The small-scale homogeneity and clearly distinguished isotope ratios of the dominant autotrophs in adjacent saltmarsh and mangrove habitats in southeast Queensland are therefore ideally suited to the study of small-scale carbon movement between adjacent habitats. Carbon isotopes of estuarine invertebrates were used to estimate the movement of particulate carbon between adjacent saltmarsh and mangroves at the tens-of-metre scale. Carbon isotope values of two crab species (Parasesarma erythrodactyla and Australoplax tridentata) and two snail species (Salinator solida and Ophicardelus quoyi) in saltmarsh closely match those of the saltmarsh grass, and suggest that the movement and assimilation of carbon occurs at a scale much smaller than has previously been examined. In mangroves, the results of this study indicate that microphytobenthos with some contribution of mangrove carbon is the most likely food source for P. erythrodactyla and A. tridentata, although contribution of carbon from saltmarsh is also possible. Under this latter scenario, carbon movement in mangroves would be considered to occur at a scale larger than that in saltmarsh habitat. A study that examined the movement and assimilation of carbon by crabs and an estuarine slug (Onchidina australis) at a finer resolution (i.e. metres) supported the original findings and indicated that the movement and assimilation of carbon occurs 5 - 8 m either side of the saltmarsh-mangrove interface. At this small-scale, the movement and subsequent foraging of crabs among habitats, the movement of particulate carbon among habitats, or a combination of crab and particulate carbon movement are three alternative models that provide plausible explanations for the pattern in carbon isotope values of crabs. Crab movement among these habitats was measured using an array of pitfall traps perpendicular to the saltmarsh-mangrove interface. To test for carbon movement, samples of detritus were collected at 2 m intervals across this same interface and the carbon isotopes analysed. For the majority of crabs (up to 90% for both species), movement up or down the shore was less than 1 m from the place of initial capture. Thus, crab movement cannot explain the trend in carbon isotope values of crabs. The pattern in detrital isotope values was similar to that of crabs and indicates that the movement of particulate carbon across the saltmarsh-mangrove interface is the most likely explanation for crab isotope ratios. Sources of carbon for estuarine invertebrates can also depend on the size of the saltmarsh patches. Examination of the movement and assimilation of carbon by crabs in saltmarsh patches of different sizes adjacent to mangroves indicates that saltmarshes less than 0.3 ha in area are subsidised by the import of allochthonous carbon, most likely from mangroves. These findings contribute substantially to our understanding of the food web value of estuarine habitats and provide an important link between landscape and food web ecology. They also have important implications for determining the conservation value of estuarine habitats with respect to their functional (food web) value. The scale-dependent sampling used in this thesis also provides important evidence for the fine-scale movement of estuarine carbon that has not previously been examined.

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Guest, Michaela A. "Movement and Assimilation of Carbon by Estuarine Invertebrates". Thesis, Griffith University, 2004. http://hdl.handle.net/10072/367539.

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In estuarine and other aquatic systems, it is possible for water to transport locally produced carbon (food) across habitat boundaries, and provide nutrition for animals remote from the carbon source. In estuarine and marine systems, early work examining the movement of carbon from saltmarsh habitats in the USA suggested that carbon may move large distances from inshore to offshore environments. Upon closer examination, however, evidence did not support this paradigm of large-scale carbon movement, referred to as the outwelling hypothesis, in some estuaries. Physical characteristics of estuaries in which large-scale carbon movement did not occur, such as restricted access to the sea, were proposed as a possible explanation, and for these estuaries, movement of carbon among estuarine habitats was considered more likely. A mosaic of saltmarsh and mangrove habitats dominate the subtropical barrier estuary of southern Moreton Bay, Queensland, but there have been no studies that examine the movement of carbon among habitats within this system. Previous studies that examine the movement of carbon have mostly been done in saltmarshes in the northern hemisphere or in tropical mangrove systems. Different vegetation and tidal regimes in temperate marshes of the northern hemisphere preclude generalisations of carbon movement to tropical and subtropical systems. Our understanding of carbon movement in tropical systems may extend to subtropical waters, but the saltmarsh-mangrove mosaic in the subtropics distinguishes them from their tropical counterparts. The mosaic of saltmarsh and mangrove habitats among the barrier islands of southern Moreton Bay thus provide a unique opportunity to examine the small-scale movement of carbon among adjacent habitats in a subtropical system. Stable isotopes of carbon have been used successfully to trace the transfer of carbon from autotrophs to consumers at a range of spatial scales. This method is able to distinguish among carbon sources where autotrophs have different ratios of 13C/12C, and consumers take on the ratio of their food source. The success of stable isotopes in clarifying food web processes, however, depends on isotope ratios changing in predictable ways as elements are processed. As isotope ratios may be influenced by changes in productivity, and differences in nutrient source, they may vary across small and large spatial scales that may confound interpretation of food web processes. In this study I measured small and large-scale spatial variability of three estuarine autotrophs (the saltmarsh grass, Sporobolus virginicus, the seagrass Zostera capricorni and the algal community epiphytic on Z. capricorni) and showed the small-scale spatial variability to be negligible and insufficient to preclude the use of carbon and nitrogen isotopes in food web studies. Large-scale variability was more pronounced and may be useful for spatial correlation of food webs for more mobile species. The small-scale homogeneity and clearly distinguished isotope ratios of the dominant autotrophs in adjacent saltmarsh and mangrove habitats in southeast Queensland are therefore ideally suited to the study of small-scale carbon movement between adjacent habitats. Carbon isotopes of estuarine invertebrates were used to estimate the movement of particulate carbon between adjacent saltmarsh and mangroves at the tens-of-metre scale. Carbon isotope values of two crab species (Parasesarma erythrodactyla and Australoplax tridentata) and two snail species (Salinator solida and Ophicardelus quoyi) in saltmarsh closely match those of the saltmarsh grass, and suggest that the movement and assimilation of carbon occurs at a scale much smaller than has previously been examined. In mangroves, the results of this study indicate that microphytobenthos with some contribution of mangrove carbon is the most likely food source for P. erythrodactyla and A. tridentata, although contribution of carbon from saltmarsh is also possible. Under this latter scenario, carbon movement in mangroves would be considered to occur at a scale larger than that in saltmarsh habitat. A study that examined the movement and assimilation of carbon by crabs and an estuarine slug (Onchidina australis) at a finer resolution (i.e. metres) supported the original findings and indicated that the movement and assimilation of carbon occurs 5 - 8 m either side of the saltmarsh-mangrove interface. At this small-scale, the movement and subsequent foraging of crabs among habitats, the movement of particulate carbon among habitats, or a combination of crab and particulate carbon movement are three alternative models that provide plausible explanations for the pattern in carbon isotope values of crabs. Crab movement among these habitats was measured using an array of pitfall traps perpendicular to the saltmarsh-mangrove interface. To test for carbon movement, samples of detritus were collected at 2 m intervals across this same interface and the carbon isotopes analysed. For the majority of crabs (up to 90% for both species), movement up or down the shore was less than 1 m from the place of initial capture. Thus, crab movement cannot explain the trend in carbon isotope values of crabs. The pattern in detrital isotope values was similar to that of crabs and indicates that the movement of particulate carbon across the saltmarsh-mangrove interface is the most likely explanation for crab isotope ratios. Sources of carbon for estuarine invertebrates can also depend on the size of the saltmarsh patches. Examination of the movement and assimilation of carbon by crabs in saltmarsh patches of different sizes adjacent to mangroves indicates that saltmarshes less than 0.3 ha in area are subsidised by the import of allochthonous carbon, most likely from mangroves. These findings contribute substantially to our understanding of the food web value of estuarine habitats and provide an important link between landscape and food web ecology. They also have important implications for determining the conservation value of estuarine habitats with respect to their functional (food web) value. The scale-dependent sampling used in this thesis also provides important evidence for the fine-scale movement of estuarine carbon that has not previously been examined.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Environmental and Applied Science
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Paillon, Christelle. "Etude de la connectivité entre les communautés de poissons de différents habitats du lagon de Nouvelle-Calédonie par microchimie des otolithes et de l'environnement". Thesis, Nouvelle Calédonie, 2014. http://www.theses.fr/2014NCAL0058/document.

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La connectivité écologique se mesure via l'estimation des mouvements réalisés par les organismes au cours de leurs vie. Parmi les outils existants, seule la microchimie des otolithes est capable de reconstruire les mouvements des poissons au cours de leur vie entière, notamment lors des migrations ontogénétiques. Son utilisation au sein des milieux oligotrophes et chimiquement peu contrastés tels que les récifs coralliens reste cependant marginale. C'est dans ce contexte que s'inscrit ce travail sur la microchimie des otolithes des poissons des récifs coralliens et mangroves de Nouvelle-Calédonie. Il se divise en deux parties. La première, méthodologique, est axée sur l'estimation du potentiel de l'outil microchimie des otolithes en Nouvelle-Calédonie, avec un chapitre sur la détermination des signatures multi-élémentaires caractéristiques des différents habitats de la Grande Terre et un chapitre sur l'étude de la relation entre la microchimie de l'environnement et celle des otolithes. La seconde partie se concentre sur l'application de la méthodologie précédemment développée a des thématiques écologiques, avec un chapitre sur le rôle des mangroves sur le cycle de vie et la distribution géographique d'une espèce de Lutjanidae, Lutjanus fulviflamma, et un chapitre centré sur les mouvements réalisés au cours de la vie de cette espèce. Les résultats démontrent que la microchimie des otolithes présente un potentiel élevé en Nouvelle-Calédonie avec un fort pouvoir de discrimination entre la mangrove et les récifs coralliens. La relation entre la microchimie de l'environnement et celle des otolithes est complexe et dépend fortement des espèces considérées. Cependant, les contrastes chimiques marqués de l'environnement se retrouvent au sein des otolithes. Les résultats démontrent une connexion forte entre les différents habitats pour L.fulviflamma, particulièrement entre la mangrove et les récifs coralliens avec une importance cruciale de la mangrove comme zone de nurserie. Trois différents patrons de mouvements entre habitats ont été identifiés. Cette diversité illustre une forte variabilité de la connectivité écologique entre les individus, avec pour certains d'entre eux, une fréquentation de l'habitat juvénile durant la phase adulte
Ecological connectivity is defined by organism movements between habitats.Among the tools used to measure connectivity, otolith microchemistry is the only one able toreconstruct the fish movement throughout their entire lifetime, and thus include ontogeneticmigrations. However, it is seldom used in oligotrophic environments that typically show poorchemical contrasts such as coral reefs. In this context, this study focused on otolith microchemistryof coral reef and mangrove fishes of New Caledonia. This work comprises two parts. First, amethodological part to assess the potential of otolith microchemistry in New Caledonia, with onechapter on the determination of multi-elemental signatures of habitats from the Main Island and onechapter on the relationships between environmental and otoliths microchemistries. Second, thepreviously developed methodology was applied to ecological questions, with a chapter on theimportance of mangrove on the life cycle and the spatial distribution of a Lutjanidae, Lutjanusfulviflamma, and a chapter on the lifetime movement patterns of this species. Results revealed ahigh potential of otolith microchemistry in New Caledonia with a high power of discriminationbetween mangroves and coral reefs. Relationships between environmental and otolithmicrochemistries were complex and species-specific. However, strong chemical contrasts in theenvironment were traduced in the otoliths. Results showed a strong connection between differenthabitats for L. fulviflamma, in particular between mangroves and reefs with a crucial importance ofmangroves as nursery grounds. Three different patterns of lifetime movements among habitats wereidentified. This diversity illustrates a high variability of ecological connectivity patterns amongindividuals, with a possible return to the juvenile habitat during the adult stage

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Castellanos-Galindo, Gustavo Adolfo [Verfasser], Ulrich [Akademischer Betreuer] Saint-Paul i Fernando [Akademischer Betreuer] Zapata. "The temporal and spatial variability of nursery habitats for fishes in macrotidal mangrove systems of Colombia and Brazil / Gustavo Adolfo Castellanos-Galindo. Gutachter: Ulrich Saint-Paul ; Fernando Zapata. Betreuer: Ulrich Saint-Paul". Bremen : Staats- und Universitätsbibliothek Bremen, 2013. http://d-nb.info/1072078481/34.

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Hendy, Ian Wyndom. "Habitat creation for animals by teredinid bivalves in Indonesian mangrove ecosystems". Thesis, University of Portsmouth, 2012. https://researchportal.port.ac.uk/portal/en/theses/habitat-creation-for-animals-by-teredinid-bivalves-in-indonesian-mangrove-ecosystems(271d9f8c-8dc0-4dff-9226-f8ebf3072199).html.

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A better understanding of the fundamental role large woody debris (LWD) plays within mangrove ecosystems may provide further insights into important ecological processes, such as wood degradation and biodiversity maintenance within mangrove forests.Though the volume of fallen wood in mangrove forests can be huge, little is known of the breakdown pathways and biodiversity maintenance of LWD in mangrove ecosystems. The degree of mangrove fauna dependent upon LWD and the need for such substratum in mangrove ecosystems may provide further insights in to the important role of woody biomass in these otherwise globally shrinking habitats due to forest harvesting. The breakdown, recycling and flux of nutrients from LWD within mangrove forests is maintained by biodegrading organisms in areas from terrestrial to marine habitats. The tidal inundation sets limits on the wood degrading communities within the mangrove forests of Sulawesi. This study presents details of the environmental and biological association of biodegrading organisms within the forests in the Wakatobi Marine Park (WMP), Sulawesi. Wood boring animals belonging to the family Teredinidae are the dominant biodegraders of LWD in the mid- to low intertidal areas of the mangrove forests. Teredinid attack greatly reduces the volume of LWD in the mid- to low intertidal areas of the forests. Within the forests, emersion time was the greatest influence of the distribution of the biodegrading organisms spanning from the supra-tidal down to the low intertidal. The response of Rhizophora stylosa prop-roots to physical damage and the activity of teredinids upon damaged prop-roots were investigated. With severe levels of root damage, the level of teredinid activity increases, resulting in root death and detrital input. However, when the roots were exposed to a superficial and moderate level of damage, an over-compensation of tissue re-growth was observed. LWD in the intertidal zone is often tunnelled by teredinids. The tunnels are blind-ending cylinders that taper to a small opening at the wood surface. However, larger openings appear when wood is heavily tunnelled and the surface is broken open. Teredinid death then leaves niches for cryptofauna. The greater the number of teredinid tunnels within LWD, the more diversity was found. Animals of particular interest were the dartfish, Parioglossus interruptus and the intertidal spider, Desis martensi found in the vacant teredinid tunnels. Desid spiders were abundant within the LWD and dartfish collected from within teredinid-attacked LWD were smaller than dartfish populations not within LWD. Desids and dartfish residing within the wood may benefit from the significantly lower temperatures within teredinid-attacked detritus compared to external air temperatures. Desis martensi has a life-history strategy centred on strong parental care, with lots of energy invested in to its young. Vulnerable stages of dartfish exploit the vacant teredinid tunnels. If it were not for the tunnels created by the teredinids the unusual behaviour adopted by dartfish and spiders would not be possible. Thus, many animals in mangrove forests of the WMP rely on LWD as a predation refuge enhanced by the teredinid tunnels within the LWD. A variety of different species were found inside teredinid attacked LWD, and the cryptic behaviour of the fauna ranged from breeding to predator avoidance. These findings indicate that in forests where wood is harvested, reduced availability of LWD will result in reduced biodiversity.

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Bakhtiyari, Majid. "Developing a quantitative approach to evaluate the health of mangrove ecosystem". Thesis, Griffith University, 2019. http://hdl.handle.net/10072/389738.

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Mangrove forests provide wide ranges of roles supporting aquatic and terrestrial biota and providing ecosystem services to humans. Over the past century, mangroves have been impacted by human activities, leading to widespread habitat loss and degradation, while efforts to restorator and rehabilitate were not very successful in most projects. However, it will always be more effective to ensure the conservation of existing mangrove habitats. Accordingly, an adequate assessment method with appropriate evaluation components is required to monitor the habitat status. The current assessment approaches more often address the structural conditions of trees and mangrove ‘forests’ which are too insensitive to pressures. There are other indicator variables that describe processes and attributes that underpin mangroves’ structures and functions. These indicator variables are likely to be more sensitive to the impacts resulted by human activities. They can therefore be used to trigger a warning and management process when conditions inside the habitat start to go wrong. The approach in this thesis was to develop an assessment method which used quantitative indicators, as indicator-based approaches and measurable information interest the stakeholders who are managing and reporting habitat status more than purely descriptive assessments. This approach initially started from a literature review and was supplemented with the use of systematic expert judgments. During this process, the competence of a suite of potential indicator variables was obtained. This competency included the variables’ ability to reflect mangrove health and their capacity for delivering ecosystem services. I also considered other criteria such as ecosystem integrity, easy, fast and cost-effectiveness of measurement as well as the time scale for the indicators to respond the pressures impacts (Chapter 2). The indicator variables must be sensitive to anthropogenic pressures, which is another critical criterion to be considered. To address this, there was a need for a scale representing the degree of human pressure / influence. This was dealt by quantifying human activities as proxies of human pressures. They were measured in Pressure Groups (PG) including land-use, hydro-morphology alteration and water quality. This method was implemented in a case study of the Moreton Bay, South East Queensland, Australia. The results reported in Chapter 3 are dimensionless quantified pressure data providing an early detection of vulnerability in mangrove communities. The results can be also used for the calibration of assessment models in future studies concerning how biotic and abiotic indicators are reflecting the pressures. In Chapter 4, the sensitivities of the competent potential indicator variables (using the results of Chapter 2) were tested against the quantified human activities (using the results of Chapter 3). I provided a set of sites ranging from the least to the highest level of anthropogenic pressure in the Moreton Bay study area. The values of the potential variables to different levels of human activities assist the selection of sensitive mangrove health metrics. The habitat characteristics such as vegetation indices in canopy level, and sediment features i.e. metals, nutrients and Chl-a showed a degree of sensitivity to human activities and accordingly were identified as capable variables for an early warning process. Identifying the appropriate health metrics may lead to the development of an Index of Mangrove Ecosystem Integrity (IMEI); this is discussed in Chapter 5. The identified indicator/field variables may be amongst the most sensitive variables to human activities. This is because the field data collection was done in those mangrove forests which are still quite stable (see Chapter 4). A higher number of variables could be included in models by extending this field work to more degraded habitats and in areas with larger magnitude of human activities. Consequently, other field variables may be discovered with lower levels of sensitivity to human activities. These sets of variables can be used as higher levels of warning process. These health metrics will assist in developing IMEI.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Environment and Sc
Science, Environment, Engineering and Technology
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Lee, Hoi-ki, i 李凱琪. "The feeding ecology of Littoraria species in Hong Kong mangroves". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B31241943.

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Krebs, Justin Micheal. "Assessing the Link Between Coastal Development and the Quality of Fish Habitat in Mangrove Tidal Tributaries". Scholar Commons, 2012. http://scholarcommons.usf.edu/etd/4108.

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To assess the potential influence of coastal development on the quality of estuarine habitat for nekton, we characterized land use and the intensity of land development surrounding small tidal tributaries of Tampa Bay. Based on this characterization, we classified tributaries as undeveloped, industrial, urban or man-made (i.e., mosquito-control ditches). Over one-third (37%) of tributaries were determined to be heavily developed, while fewer than one-third (28%) remain relatively undeveloped. We then examined the nekton community from eleven tributaries in watersheds representing the defined land-use classes. Whereas mean nekton density and species richness were both independent of land use, nekton-community structure differed between non-urban (i.e., undeveloped, industrial, ditches) and urban tributaries. In urban tributaries, the community was skewed towards high densities of poeciliid fishes while typically dominant estuarine taxa were in low abundance or nearly absent. Densities of economically important taxa in urban creeks were also only half that observed in most non-urban creeks, but were similar to those observed in mosquito ditches. Furthermore, six of nine common taxa were found to be in relatively poor condition (6-22% smaller in mass), or were rarely collected, in urban creeks. Reproductive output was reduced for both sailfin mollies (i.e., fecundity) and grass shrimp (i.e., very low densities and few ovigerous females) in urban tributaries. Canonical correspondence analysis differentiated non-urban and urban tributaries based on greater impervious surface, less natural mangrove shoreline, higher frequency of hypoxia and lower, more variable salinities in urban tributaries. These characteristics explained 48% of the variation in nekton data, including the high densities of poeciliid fishes, greater energy reserves in sailfin mollies and low densities of several common nekton and economically important taxa from urban creeks. Our results suggest that urban development in coastal areas has the potential to alter the quality of habitat for nekton in small tidal tributaries as reflected by variation in nekton metrics between urban and non-urban tributaries. To further evaluate the link between coastal development fish-habitat quality, we examined the relationship between landscape development intensity (LDI) and the body condition of juvenile sailfin mollies (Poecilia latipinna), a dominant forage fish in tidal tributaries. Morphometric condition, measured as least-square mean dry weight, did not differ statistically among tributaries (P = 0.85). In contrast, biochemical condition, measured as the concentration of triacylglycerol (TAG), the predominant storage lipid, was significantly different among tributaries (P < 0.0001). LDI explained less of the observed variation in TAG content (R2 = 0.18, P = 0.11) than long-term mean salinity (R2 = 0.81, P < 0.0001), which also tended to be lower in more intensively developed watersheds. We hypothesized that urban land use, characterized by considerably greater impervious surface than undeveloped lands, contributed to altered watershed hydrology, high freshwater runoff and low salinities in urbanized creeks. Together these factors appear to foster conditions conducive to lower energetic cost of osmoregulation in urban creeks, and development of a benthic microalgal community of greater nutritional value than the food resources available in non-urban tributaries. To our knowledge, this is one of the first studies to relate urbanization to the condition of resident fishes. While not directly related to coastal urbanization, the level of predation risk within a habitat is a direct measure of habitat quality that could be reflected by the reproductive strategy of potential prey. To evaluate the use of reproductive metrics of fish-habitat quality, we examined reproduction in P. latipinna from eleven tidal tributaries. Our results revealed a gradient along which females produced many, small offspring at one extreme (mean=42 offspring, 17 mg each) and fewer, larger offspring at the other (24 offspring, 29 mg each). Reproductive allotment ranged from 14.9 - 21.5% maternal biomass. Based on our observation of divergent reproductive strategies, we experimentally tested the null hypothesis of no difference in predation risk among tributaries using a novel quantitative approach to estimate predation. We predicted greater risk in tributaries where mollies produced many, small offspring. Tethering confirmed increasing risk from 16.2 ± 5.3% SE to 54.7 ± 3.6% fish lost h-1 across sites in agreement with observed variation in reproduction. Predation was unexpectedly higher than predicted at one of the four sites suggesting that additional factors (e.g., food) had influenced reproduction there. Our results provide insight into the well-studied concept of predator-mediated variation in prey reproduction by quantitatively demonstrating differential risk for mollies exhibiting divergent reproductive strategies. While the observed range of variation in reproductive traits was consistent with previous studies reporting strong predator effects, higher than expected predation in one case may suggest that the prey response does not follow a continuous trajectory of incremental change with increasing predation risk, but may be better defined as a threshold beyond which a significant shift in reproductive strategy occurs.

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Silverman, Noah L. "Assessing the consequences of hurricane-induced fragmentation of mangrove forest on habitat and nekton in Big Sable Creek, Florida". [Tampa, Fla] : University of South Florida, 2006. http://purl.fcla.edu/usf/dc/et/SFE0001751.

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Jordão, Marcelo Di Lello. "Distribuição espacial dos foraminíferos no perfil transversal ao manguezal da margem da baía de Sepetiba-RJ: habitat e paleoambiente". Universidade do Estado do Rio de Janeiro, 2009. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=4136.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Os foraminíferos de zona entre-marés são amplamente utilizados como na reconstituição paleoambiental holocênica. Entretanto, a despeito dos manguezais, estudos com foraminíferos são relativamente escassos. A estrutura do habitat e seu grau de exposição atuam na distribuição espacial das espécies de zona entre-marés. Em um perfil transversal ao manguezal que margeia a baía de Sepetiba (RJ), foi investigada a influência parâmetros estruturais do habitat e da riqueza na distribuição espacial dos foraminíferos do manguezal. Os parâmetros escolhidos neste estudo foram serapilheira, litologia, matéria orgânica total, microtopografia, zonação botânica, espécies botânicas, altura média das árvores e densidade de árvores. Um testemunho de 144 cm também foi descrito em termos da sua litologia, matéria orgânica total, composição biogênica, incluído foraminíferos. O perfil apresentou textura silte argilosa, matéria orgânica total concentrada por todo manguezal e a serapilheira acumulada principalmente no mangue superior. Os forminíferos (24) ocorreram apenas no manguezal, com predomínio de aglutinantes e presença significativa de formas calcárias. A densidade de testas se concentrou no mangue superior. A. beccarii f. tepida, E. excavatum, A. mexicana, Q. seminulum e T. inflata foram as espécies mais constantes. A diversidade não apresentou variabilidade espacial significativa e foi marcada pela baixa dominância e alta equitabilidade. Notou-se diferença significativa da riqueza de foraminíferos entre habitats expostos e protegidos. A riqueza específica apresentou moderada correlação com a serapilheira e densidade de árvores. A. mexicana e H. wilberti apresentaram moderada correlação com a riqueza. Q. seminulum apresentou significativa correlação com a matéria orgânica total e altura média das árvores. T. inflata apresentou significativa correlação com a riqueza e serapilheira. Em relação ao testemunho, foi possível identificar três paleoambientes de baía restrita: infralitoral, mesolitoral e supralitoral. O manguezal este presente entre o nível 124 62 cm e a planície hipersalina a partir do nível 24 cm.
Intertidal foraminifera are widely used for reconstructing the Holocene environmental. However, despite the mangroves, studies of foraminifera are relatively scarce. The structure of the habitat and its degree of exposure acts in the spatial distribution of intertidal species. In a profile across the mangrove which borders the Bay of Sepetiba (RJ), was investigated the influence of habitat and structural parameters in spatial distribution of foraminifera in the mangrove. The parameters chosen in this study were litter, lithology, total organic matter, topography, botanical zones, botanical species, average tree height and density of trees. A core (144 cm) was also descript in terms of its lithology, total organic matter, biogenic composition, including foraminifera. The profile presented clayey silt texture, total organic matter concentrated around mangrove and litter accumulated mainly in mangrove higher. The foraminifera (24) occurred only in the mangrove, dominated by the agglutinanted species, but with significant presence of calcareous species. The density of tests concentrated in mangrove higher. A. beccarii f. tepida, E. excavatum, A. mexicana, Q. seminulum and T. inflata were more constant. The diversity showed no significant spatial variability, and was marked by low dominance and high evenness. There was a significant difference of the species richness between exposed and protected habitats. The species richness showed moderate correlation with litter and density of trees. A. mexicana and H. wilberti showed moderate correlation with species richness. Q. seminulum showed significant correlation with total organic matter and average height of the trees. T. inflata showed significant correlation with the richness and the litter. In the core, it was possible to identify three paleoenvironments of confined bay: infralitoral, mesolitoral and supralitoral. The mangrove occurred between the level 124cm and 62 cm, and hipersaline flat from the level 24 cm.

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Machemer, Ethan G. P. "A Predictive Habitat Model for Rainbow Parrotfish Scarus guacamaia". NSUWorks, 2010. http://nsuworks.nova.edu/occ_stuetd/212.

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The rainbow parrotfish Scarus guacamaia is a prominent herbivore in the coastal waters of southeastern Florida whose life history is strongly linked to a dependence on both mangrove and coral reef habitats. Rainbow parrotfish in turn serve in maintaining the health of coral reefs by keeping algal populations in check. This study used NOAA Fisheries data from the Mangrove Visual Census and the Reef Visual Census in Biscayne Bay and Upper Florida Bay. Observations of abiotic factors at individual sites were used to correlate and predict presence and absence of this species. This was done to visualize habitat presence and ontogenetic shifts present in this species between juvenile and adult stages through ArcGIS mapping. Logistic regression analysis was used to predict presence or absence using the environmental variables of temperature, dissolved oxygen, salinity, average depth, distance from channel openings, mangrove presence, temperature Δ, and salinity Δ. Average depth, distance from channel openings, temperature Δ and salinity Δ were significant in predicting the presence of this species, while salinity, temperature, dissolved oxygen, and mangrove presence were not. Conservation efforts for this species, listed as vulnerable under the IUCN, need to be given greater consideration. The health of this and other parrotfish may have a greater impact on coral reef ecosystems across the Caribbean Sea than currently acknowledged and management breadth and priorities should be adjusted to reflect this role.

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Kiskaddon, Erin Paige. "Feeding Patterns and Trophic Food Web Dynamics of Armases cinereum Across a Mangrove/Upland Ecotone". Scholar Commons, 2016. http://scholarcommons.usf.edu/etd/6525.

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The feeding ecology of a common saltmarsh crab, Armases cinereum (Armases), was investigated to determine how habitat (mangrove vs. ecotone, natural mangrove vs. modified mangrove fringe) influenced this species’ feeding behavior and trophic ecology in its southwestern Florida, USA, distribution. In the laboratory, Armases’ preference for mangrove material was examined using leaves of three mangrove species (Avicennia germinans, Laguncularia racemosa, and Rhizophora mangle) and leaves of different degradation levels (fresh, senescent, and partially-decomposed). Leaf material from A. germinans was preferentially consumed over the other taxa at fresh and partially-decomposed levels of leaf decay. When Armases were offered a choice between four common upland vegetation types (Iva frutescens, Borrichia frutescens, Nephrolepis biserrata, and Stenotaphrum secundatum), the preferred mangrove from the previous experiment (A. germinans, partially-decomposed), and an animal prey item (Gryllodes sigillatus, cricket), Armases displayed greatest selectivity for the animal prey item and high selectivity for both I. frutescens and A. germinans plant taxa (Manly-Chesson α selectivity and Chesson ϵ electivity). Field-based stable isotope analysis was used to determine trophic position and reconstruct dietary proportions of Armases across three pairs of natural and heavily-modified sites within Tampa Bay to determine whether Armases feeding behavior is impacted by the presence of upland forest adjacent to mangrove forest habitat. Analysis of trophic position based on δ15N signatures of Armases from each of the six populations revealed that Armases in habitats with modified connectivity had lower trophic variability and significantly higher average trophic position compared to Armases sampled from the three sites with natural connectivity. Stable isotope diet reconstruction using the Bayesian mixing model SIMMR further established Armases preference for animal-derived food material in habitats with natural and modified connectivity. This preference is likely driven by high selectivity for sources rich in Nitrogen (i.e., animal tissue, partially-decomposed A. germinans material, and I. frutescens). I determined that the use of laboratory experiments in conjunction with stable isotope mixing models is important in accurately investigating feeding preferences of Armases in mangrove intertidal regions. Together, my results show that the diet of Armases is broadly omnivorous and populations can be influenced by the heterogeneity of their habitat. Further feeding experiments, dietary analyses and a longer sampling period are needed to more definitively identify the patterns of Armases detritivory in mangrove and ecotonal upland habitats.

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Idrus, Rijal. "Hard Habits to Break: Investigating Coastal Resource Utilisations and Management Systems in Sulawesi, Indonesia". Thesis, University of Canterbury. Geography, 2009. http://hdl.handle.net/10092/3054.

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This research investigates the paradox that many coastal communities in developing countries are resource rich but income poor. Another aspect of this paradox is the belief that local communities possess traditional knowledge that respects nature. This belief contrasts the fact that major tropical coastal ecosystems, namely coral reefs and mangroves, are being destroyed at rapid and increasing rates, in many cases by the people whose livelihoods depend on them. These paradoxical circumstances lead to a central question: if the sustainability of coastal resources is vital for the livelihood of local communities, why are these resources being degraded, often to the point of complete destruction? This study explores the motives and consequences of destructive methods of coastal resource utilisation and examines the potential for sustainable livelihoods based on coastal resources currently under threat from destructive use patterns. The analysis is based on a field study conducted in 2006 and 2008 in eleven sites around the island of Sulawesi, Indonesia. This area is characterised by great biodiversity, including one of the highest marine biodiversities in the Asia-Pacific region. Coral and mangrove ecosystem resource use was found to be driven by different processes and activities; hence the destructive practices impacting both ecosystems were also different. Blast and poison fishing were the most widespread destructive resource use methods found for coral reefs whereas large-scale habitat conversion was responsible for mangrove ecosystem reduction. In the field both resources were found to be under enormous anthropogenic pressures, with published data suggesting that only 5.8% of Indonesian coral reefs are currently in excellent condition and only 38% of mangrove cover remaining in Sulawesi relative to that of 25 years ago. The dynamics of these coastal resources, and of their destruction, are classic examples of the ’tragedy of the commons’. Research findings further indicate that formal institutions tasked with managing these resources have not been able to promote their effective conservation. An array of competing demands and conflicting interests, coupled with inefficient institutional arrangements and under-investment, have rendered inadequate many resource management efforts, including the externally-imposed concepts, allowing destructive patterns of resource utilization to persist. Local communities are disempowered when confronted with (1) the intricate network of destructive-fishing actors targeting coral reefs, or (2) large company-government bureaucracy collusions allowing mangrove conversion. The existence of this collusive network must be considered in any effort to address problems of effective management. Empirical insights suggest that conservation at local level has to face the challenges of market-driven resource extraction at a global scale. Only when a coastal community manages to overcome the dilemma in managing common-pool resource, conservation measures can be implemented and a degree of sustainability attained. Findings from this research have important implications for the discourses on coastal resource policy and research. This research advances the discussions to the area where the core of conflict of interests among stakeholders took place, and yet has rarely been addressed previously. The synthesis from this study provides a strong basis to understand the nature of asymmetric relations amongst the resource stakeholders, and therefore will help in generating effective policies for a fairer coastal resource management regime.

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Ellis, Jeffrey M. "A Quantitative Assessment of the January 2010 Cold Spell Effect on Mangrove Utilizing Coral Reef Fishes from Biscayne National Park, Florida". NSUWorks, 2015. http://nsuworks.nova.edu/occ_stuetd/377.

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This study examined the effects of the January 2010 cold spell on mangrove utilizing coral reef fishes off the southeast coast of Florida, USA, in the vicinity of Biscayne National Park (BNP). An ongoing, fishery-independent mangrove visual survey documenting fish assemblages in BNP provided data from the years 1998 to 2014 for examination. Of particular interest were the presence, abundance, and size structure for five mangrove utilizing coral reef fishes: sergeant major (Abudefduf saxatilis), yellowfin mojarra (Gerres cinereus), schoolmaster snapper (Lutjanus apodus), gray snapper (Lutjanus griseus), and great barracuda (Sphyraena barracuda). These species were selected for analysis due to their economic and ecologic importance, their potential as environmental indicators, their connectedness to multiple habitats, and their abundance within the available data set. Data were collected using a modified visual ‘belt transect’ method, consisting of 60 m2 transects running parallel to the mangrove shorelines. Data for average length of fish were reconstructed to form standard normal distributions and the resulting lengths were assigned to various age-classes to create species-specific length-frequency distributions. Variations in presence and abundance were examined across three time periods (1998-2009; 2010-2011; 2012-2014), as well as comparisons of length-frequency distributions. Following the January 2010 cold spell, the presence and abundance values for the two years immediately following the event were significantly decreased compared to the years prior to the cold spell for most of the five species at either mainland (ML) or leeward key (LK) locations. Additionally, the presence and abundance estimates typically remained statistically decreased when compared against the remaining years in the available data set. The size structures for the majority of the five species at either location, however, were not consistently significantly different between the three time periods, as was hypothesized. Instead, the analyses showed mixed results, with the size structure typically shifting towards smaller individuals immediately following the event. These findings suggest that drops in water temperature resulting from cold spells are capable of directly impacting mangrove utilizing reef fish species, albeit to varying degrees depending on various factors, such as physiological tolerances, ecological life history strategies, and habitat requirements.

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Webley, James A. C. "The ecology of the mud crab (Scylla serrata): their colonisation of estuaries and role as scavengers in ecosystem processes". Thesis, Griffith University, 2008. http://hdl.handle.net/10072/367091.

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Scylla serrata is a portunid crab which can attain a weight of over 2 kg and a carapace width exceeding 250 mm. It is distributed throughout the Indo-West Pacific extending down the east coast of Africa, and both the east and west coasts of Australia. In Australia it is commonly known as the mud crab because it occurs within muddy, mangrove-lined bays and estuaries. Mud crabs are generalist predators eating most small, slow moving animals which they can catch, but they are also vigorous scavengers. Being scavengers, they are readily caught in baited traps set by commercial and recreational fishers, and are the stock for these popular fisheries. Female crabs spawn offshore and larvae spend a period in the plankton where they develop into postlarvae or megalopae...
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Environment
Science, Environment, Engineering and Technology
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Hamilton, Catherine Faye. "Habitat and Seasonal Distribution of the North American River Otter (Lontra canadensis) and Vertebrate Species Assemblages in Two Protected Areas of the Florida Everglades". NSUWorks, 2014. http://nsuworks.nova.edu/occ_stuetd/23.

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The Florida Everglades ecosystem is threatened by human development, increased pollution, freshwater scarcity, and invasive species; factors that have negatively impacted the Everglades and native species health and populations. Man-made canals and levies have redirected the natural flow of fresh water from Lake Okeechobee into the Florida Everglades, starving central and south Florida ecosystems of necessary fresh water and nutrients. Through the efforts of the Comprehensive Everglades Restoration Project (CERP), freshwater is being redirected back into central and south Florida, returning the sheet flow of water back into the Everglades. Monitoring species abundance in the Everglades is a beneficial conservational tool for assessing restoration efforts from CERP. As a semi-aquatic apex predator, river otters (Lontra canadensis) are a useful health bio-indicator for the Florida Everglades. In order to conduct future population studies of river otters in the Florida Everglades, it must first be ascertained where they can be found and what time of year they are most likely to be sighted. For this study, Moultrie infrared game cameras were used to photograph the presence or absence of river otters within the five main habitats in the Everglades; the pinelands, hardwood hammock, cypress swamp, marsh prairie, and mangrove estuary at two protected areas in the Florida Everglades (Big Cypress National Preserve and Fakahatchee Strand State Park). River otters were most frequently sighted in the hardwood hammock habitat, but were also found in the cypress swamp. The large majority of river otter sightings occurred during dry season, which is thought to be a function of restricted water availability and aquatic mobility. Future population studies of river otters would be most productive in the hardwood hammock and cypress swamp habitats during dry season. Game camera images along with field opportunistic sightings, resulted in a variety of species documented. This provided valuable information of species richness and distribution within and amongst the habitats. The hardwood hammock was found to be the most species rich habitat, having over half the species observed in the study in this habitat. The Aves class was the most abundantly observed in the Everglades, and was most frequently sighted during the dry season. As a refuge for migratory birds, the Everglades house the majority of bird species during the winter months, which occur during dry season. The Aves class was most frequently sighted in the pinelands habitat during dry season. This habitat, being the highest in elevation and therefore the driest, shows a stronger resemblance to most northern bird habitats then does the water-saturated wetlands found throughout the Everglades. The mangrove estuary was the most commonly occurring outlier, having the least species overlap when compared to the other habitats. All other habitats in the Everglades are freshwater wetlands, while the mangrove estuary is a brackish environment, which limits the species that are unable to tolerate saline conditions. Further studies of species abundance throughout the Everglades will aid in monitoring CERP restoration efforts over time.

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"Ecology of fishes in mangrove and non-mangrove habitats in eastern Kong Kong". 2005. http://library.cuhk.edu.hk/record=b5892547.

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Nip Hin Ming.
Thesis (M.Phil.)--Chinese University of Hong Kong, 2005.
Includes bibliographical references (leaves 132-150).
Abstracts in English and Chinese.
Declaration --- p.i
Abstract --- p.ii
Acknowledgements --- p.vi
Table of Contents --- p.vii
List of Tables --- p.ix
List of Figures --- p.xi
Chapter Chapter 1 --- General introduction --- p.1
Chapter Chapter 2 --- Fish communities in the shallow soft shores of eastern Hong Kong
Introduction --- p.4
Materials and methods --- p.7
Results --- p.11
Discussion --- p.21
Chapter Chapter 3 --- Mangroves as fish nurseries: a case study in subtropical southeastern China
Introduction --- p.33
Materials and methods --- p.37
Results --- p.41
Discussion --- p.113
Conclusion --- p.124
Chapter Chapter 4 --- General discussion --- p.126
Chapter Chapter 5 --- General conclusions --- p.131
References --- p.132

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Ortega, Alejandra. "Fingerprinting Marine Macrophytes in Blue Carbon Habitats". Diss., 2019. http://hdl.handle.net/10754/660253.

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Seagrass, mangrove, saltmarshes and macroalgae - the coastal vegetated habitats, offer a promising nature-based solution to climate change mitigation, as they sequester carbon in their living biomass and in marine sediments. Estimation of the macrophyte organic carbon contribution to coastal sediments is key for understanding the sources of blue carbon sequestration, and for establishing adequate conservation strategies. Nevertheless,identification of marine macrophytes has been challenging and current estimations are uncertain. In this dissertation, time- and cost-efficient DNA-based methods were used to fingerprint marine macrophytes and estimate their contribution to the organic pool accumulated in blue carbon habitats. First, a suitable short-length DNA barcode from the universal 18S gene was chosen among six barcoding regions tested, as it successfully recovered degraded DNA from sediment samples and fingerprinted marine macrophyte taxa. Second, an experiment was performed to test whether the abundance of eDNA represents the content of organic carbon within the macrophytes; results supported this notion, indicating a positive correlation (R2 = 0.85) between eDNA and organic carbon. Third, using the chosen barcode, eDNA of marine macrophyte was identified from sediments of seagrass meadows and mangrove forests in the Arabian Red Sea, to further estimate contributions to the organic carbon pools. Estimations based on eDNA were compared against estimations of organic carbon based on stable isotope analyses from the same sediments; results from both methods were similar. In addition, this research provided the first quantitative evidence of the contribution of macroalgae to coastal and oceanic carbon pools. Hitherto, macroalgae have been ignored in blue carbon assessments because their fingerprinting was challenging and there was no evidence of their carbon export. The results of this dissertation demonstrate that eDNA offers an unprecedent taxonomic discrimination, and resolve the contribution of marine macrophytes to the organic pools in blue carbon sediments.

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Carrasquilla, Mauricio. "Ecological importance of nearshore habitats to sustain small-scale fisheries". Thesis, 2018. https://dspace.library.uvic.ca//handle/1828/9328.

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In the marine realm, there has been considerable habitat degradation caused by multiple human disturbances that often act synergistically, strongly affecting fish and invertebrate populations and, consequently, one of the major stakeholders of these resources, fishers. However, the mechanisms underlying how marine habitats support fisheries remain understudied. In this dissertation I examined the importance of fish habitat at global, regional and local scales in two distinct systems (mangrove habitats in the tropics and rockfish habitats in inshore waters of Vancouver Island) combining a suite of different approaches. First, I explored the mangrove-fishery linkage relationship by conducting a global meta-analysis. I found strong evidence supporting the importance of mangrove area to enhance fisheries. This relationship, however, varied across countries, likely based on regional geomorphological settings and fishery management policies. Subsequently, I determined the use of mangrove and adjacent habitats by fish in a tropical lagoon system in the continental Caribbean (Colombia), systems often overlooked in the Caribbean when analyzing mangroves as fish habitat. I collected fish with gillnets at different distances from mangroves and at different sites within the same lagoon system. While fish used mangroves, fish abundance was not higher in these habitats compared to adjacent ones, as predicted. However, diversity tended to be higher in mangroves. Nevertheless, the major driver affecting abundance, diversity and biomass was salinity. That is, diversity and abundance decreased as salinity increased. Next, I used a Local Ecological Knowledge approach to explore the mangrove-fishery linkage relationship because fishers are seldom incorporated into such relationships. By conducting semi-structured interviews I found that fishers fish close to their village and to mangroves, that in addition to fishing they use mangroves for firewood and as construction material. Fishers also agreed that mangroves are important for their fishing activity, as these habitats are critical for fish and crustaceans caught in the system. Finally, I examined the importance of derived benthic parameters for rockfish abundance and distribution at large spatial scales (100s km) in inshore waters of Vancouver Island. I established that higher complexity better explains presence and higher abundance of rockfish. Furthermore, the results provided valuable information for fishery and spatial management and habitat conservation to help recover rockfish populations. All together, these findings highlight the urgency to preserve coastal marine habitats for both juvenile and adult marine organisms to sustain small-scale fisheries as a food source and for traditional purposes. While conserving habitats is a key component of a broader and more complex ecosystem approach that includes overfishing and other anthropogenic pressures, in the absence of a holistic approach the chances of success are minimal.
Graduate
2019-04-18

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Ting, Hsu Chih, i 許至廷. "Copper Pollution in Chuwei Mangrove Habitat". Thesis, 1999. http://ndltd.ncl.edu.tw/handle/41167378487066756684.

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碩士
國立中興大學
水土保持學系
87
Abstract Due to pollution and destruction, mangrove habitat in Taiwan has been decreased rapidly. Copper is one of the main pollutants in Chuwei mangrove. The purposes of this study were to examine the copper concentration and effects of copper pollution on the mangrove habitat by mean of soil and tissue analysis. Because of fine texture, rich in organic matter and periodical flooding, mangrove soils are susceptible to copper accumulation. Copper concentration（0.1NHCl extracted） in Chuwei mangrove soil is 90.5±17ppm. While the maximum copper adsorption capacity of soil is 2632±265ppm. There is still some capacity available for trapping copper in mangrove soils. With the function of water purifying, mangrove habitat can be as a vegetative buffer strips for filtering pollutants in estuary. Obvious accumulation of copper（101.5±23.79ppm） in crabs can be examined in the mangrove ecosystem. Copper pollution should be concerned in the system for the phenomenon of copper accumulation.

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MacDonald, James A. "Variation among mangrove forests as fish habitat the role of prop-root epibionts, edge effects and behavior in neotropical mangroves". 2008. http://hdl.rutgers.edu/1782.2/rucore10001600001.ETD.17349.

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Nakahara, Bryan A. "Utilization of mangrove habitat by megafauna along the southern coast of Molokai, Hawaiʻi". Thesis, 2007. http://hdl.handle.net/10125/20808.

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Chung, Hui-wen, i 鍾慧雯. "Study on Habitat and Impacts Managementof the Mangroves in Northern Kaohsiung". Thesis, 2013. http://ndltd.ncl.edu.tw/handle/26534207558076009649.

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碩士
國立中山大學
海洋事務研究所
102
Abstract Mangroves plays important roles on sustaining ecological systems and providing environmental protection from human societies. Various land-use changes in coastal areas are related to the changes of the mangrove ecosystem. To monitor the impacts from the changes. Northern Kaohsiung is one of the most important aquaculture areas. For a long time over sixty years development on the aquaculture, the mangroves and aquaculture have existed as a special cultural and ecological landscape. Using a case study approach with questionnaires, in-depth interviews, direct observation to investigate the status of mangrove growth and the mangrove habitat change historically in the study. We also analysed the sources of impacts to understand the causes of local mangrove diminishing, and assessing which impact will continue to increase. The results have revealed that after filling and exploitation the coastal areas, the distribution of the Northern Kaohsiung mangroves has changed after Japanese-occupied period. The potential mangrove habitat changed from lagoon shore and claybank into five habitats categories, i.e., a big gutter, common ditch, pond ditch, salt pan wetland and unirrigated farmland. The habitat size changed from small and coherent into large and broken. The aquaculture methods changed over the last 30 years and the cooling-water from natural gas processing factories has been applied on the aquaculture recently, which have caused the mangroves in pond ditch habitat unresisting. At last, this study will divided the sources of impacts into two categories: water sources and non-water sources, then discussed trends of changes of impacts. Keywords: mangrove, habitat, impact, aquaculture, cooling-water

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Baldry, Kimberlee. "Exploring the ecosystem engineering ability of Red Sea shallow benthic habitats using stocks and fluxes in carbon biogeochemistry". Thesis, 2017. http://hdl.handle.net/10754/626353.

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The coastal ocean is a marginal region of the global ocean, but is home to metabolically intense ecosystems which increase the structural complexity of the benthos. These ecosystems have the ability to alter the carbon chemistry of surrounding waters through their metabolism, mainly through processes which directly release or consume carbon dioxide. In this way, coastal habitats can engineer their environment by acting as sources or sinks of carbon dioxide and altering their environmental chemistry from the regional norm. In most coastal water masses, it is difficult to resolve the ecosystem effect on coastal carbon biogeochemistry due to the mixing of multiple offshore end members, complex geography or the influence of variable freshwater inputs. The Red Sea provides a simple environment for the study of ecosystem processes at a coastal scale as it contains only one offshore end-member and negligible freshwater inputs due to the arid climate of adjacent land. This work explores the ability of three Red Sea benthic coastal habitats (coral reefs, seagrass meadows and mangrove forests) to create characteristic ecosystem end-members, which deviate from the biogeochemistry of offshore source waters. This is done by both calculating non-conservative deviations in carbonate stocks collected over each ecosystem, and by quantifying net carbonate fluxes (in seagrass meadows and mangrove forests only) using 24 hour incubations. Results illustrate that carbonate stocks over ecosystems conform to broad ecosystem trends, which are different to the offshore end-member, and are influenced by inherited properties from surrounding ecosystems. Carbonate fluxes also show ecosystem dependent trends and further illustrate the importance of sediment processes in influencing CaCO3 fluxes in blue carbon benthic habitats, which warrants further attention. These findings show the respective advantages of studying both carbonate stocks and fluxes of coastal benthic ecosystems in order to understand the spatial, temporal and net effects of their metabolism on the coastal ocean.

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Brady, Aisling. "The Distribution of Coral, Reefs and Coastal Habitats in North Central Cuba". Thesis, 2008. http://hdl.handle.net/1807/17155.

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Coral communities have begun to form under small inlet-style bridges along the causeway connecting Cayo Coco to Cayo Guillermo. To understand how these bridge-reefs formed and characterize their attributes relative to surrounding communities, a combination of ecological observations and 13C isotopes were analyzed from the bridges and surrounding reefs, mangrove channels and seagrass patches. Hierarchical Cluster Analysis, Detrended Correspondence Analysis and Canonical Correspondence Analysis were carried out to group which physical attributes contributed to the coral communities in the bridge-reefs and also which habitats they were most similar to, with respect to coral and benthic composition. Bridge reef coral assemblages resembled shallow patch reefs and mangrove channels, while benthic coverage was similar to mangrove channels. Organic matter was from combined seagrass and mangrove sources, with mangrove dominating in some regions more than others. This work demonstrates that habitats within the seascape are inter-related through varying mechanisms and development is multi-dimensional.

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Kober, Kerstin [Verfasser]. "Foraging ecology and habitat use of wading birds and shorebirds in the mangrove ecosystem of the Caéte Bay, Northeast Pará, Brazil / vorgelegt von Kerstin Kober". 2004. http://d-nb.info/975386050/34.

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