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Competence development in marine protected area professionals: a case study of the South African Marine Protected Area Management Training Course (SAMPATC)Lewis, Sebastian Giulio January 2012 (has links)
This study reviews a training programme on Marine Protected Area (MPA) management. It notes that although MPAs are well promulgated under legislation, reports have found that there are still key challenges facing the management of these areas. The research examines how the course was developed following the Lemm and Attwood (2003) report and designed to develop competences for effective MPA management. The aim is to identify how a MPA management training course produced competences apposite to the workplace settings of the participants. An interpretive case study method was used, in two phases. The first phase explored salient issues in MPA management in South Africa through analysis of the two key ‘state of MPA management’ reports and interviews with MPA professionals. The second was an analysis of the South African Marine Protected Area Management Training Course. This involved interviews with course designers, a review of the course materials, interviews with past course participants, and an analysis of course evaluations. Evidence emerged that supported the following findings: Challenges and problems facing MPA management still exist. Competence in key areas of MPA management was addressed in an effective work-integrated approach. Social learning was a key process in the development of these competences. The competences articulate well with the workplace of participants. Gaps exist between some of the management issues and the competences developed by the course, and some aspects of the course design are ineffective. From these findings it is concluded that: The course took up the majority of issues in MPA management through the development of key competences. The course design facilitated the development of these competences. The competences developed through the course are relevant to the workplace of MPA professionals. The research found that the course adequately addresses issues in MPA management through the development of competences. Some recommendations for improvements are made.
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Monitoring seasonal and annual changes in the mesozooplankton community of the Indian River Lagoon, FloridaUnknown Date (has links)
In estuaries, like the Indian River Lagoon, mesozooplankton have a vital role in the food web by connecting trophic levels. In this study, mesozooplankton abundance and species composition were monitored weekly on the incoming and outgoing tides from September 2006 to May 2009. For the incoming tide, the mean abundance was 2298.2 mesozooplankton/m3 (+/-325.2), and for the outgoing tide the mean abundance was 1180.0 mesozooplankton/m3 (+/-153.1). The mesozooplankton abundance on the incoming tide was significantly greater than on the outgoing tide. The most abundant type of mesozooplankton was the copepod Acartia tonsa, representing 35.0% and 52.1% of the individuals on the incoming and outgoing tides respectively. Mesozooplankton abundance values were compared with environmental data obtained from the South Florida Water Management District. The strongest positive correlation was found between chlorophyll a concentrations and A. tonsa abundance, likely due to phytoplankton being the primary food source for A. tonsa. / by Miranda Hoover Kerr. / Thesis (M.S.)--Florida Atlantic University, 2009. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2009. Mode of access: World Wide Web.
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Carbon cycling in continental slope sediments : the role of benthic communitiesGontikaki, Evangelia January 2010 (has links)
Previous pulse-chase experiments have revealed a wide diversity of benthic response patterns to organic matter (OM) input depending on environmental setting, benthic community structure and experimental conditions i.e. quantity and quality of the added OM. However, the mechanisms and interaction of environmental and biological factors that produce an observed response pattern are poorly understood. The present thesis set out to improve our current understanding on the set of parameters that determine benthic response patterns. The core of this study was based on two pulse-chase experiments in two bathyal settings: the Faroe-Shetland Channel (FSC) and the SW Cretan slope in the E. Mediterranean (E. Med). The sub-zero temperatures in the FSC enabled the observation of the benthic response in “slow-motion” and showed that the response is not static but instead might go through various “phases”. In the warm E. Med, C processing rates were considerably lower compared to previous measurements in adjacent regions. The discrepancy was attributed to the particularly refractory sedimentary OM at the sampling station with apparent consequences for the physiological state of the bacterial community. Both experiments showed that bacterial metabolism and its regulation is a key factor determining the reaction of the benthic community to OM inputs. This thesis provided further understanding on the short-term fate of organic C in deep-sea sediments but also raised certain issues that could be addressed in future studies.
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Consumptive effects of predatory fish reduce wetland crayfish (Procambarus spp.) recruitment and drive species turnoverUnknown Date (has links)
Trade-offs in traits conferring success in permanent and ephemeral habitats are often at odds with few species being able to persist in both types of environments. I examined the effect of sunfish predators on two species of south Florida crayfish to establish the mechanism that limits one species, Procambarus alleni, to short-hydroperiod environments. The crayfish assemblage response to a gradient of sunfish predators and the effect of predation on P. fallax alone was examined. I also examined the effects of sunfish on crayfish growth and quantified activity levels and risky behaviors of both crayfish species. P. alleni dominated at low sunfish densities but dominance shifted with increasing sunfish density. P. alleni was more active and likely to initiate risky behaviors, suggesting that sunfish predators remove the more active P. alleni, reducing their numbers disproportionally to those of P. fallax and allowing P. fallax to dominate crayfish assemblages in long-hydroperiod wetlands. / by Christopher M. Kellogg. / Thesis (M.S.)--Florida Atlantic University, 2011. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2011. Mode of access: World Wide Web.
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Diet variation and the consumptive effects of native centrarchids on benthic macroinvertebrates in wetlandsUnknown Date (has links)
Fish predation can have structuring effects in aquatic communities, but the most important fish predators are not always immediately obvious. Generalist fish predators often occupy similar habitats and consume similar prey making determination of their consumptive impacts difficult. Understanding these consumptive impacts is important for understanding complex wetland food webs. I collected warmouth (Lepomis gulosus), bluespotted sunfish (Enneacanthus gloriosus), and dollar sunfish (Lepomis marginatus) in two seasons from sloughs for both diet and bioenergetics analysis. Macroinvertebrates dominated diets of the three species, and nonparametric analyses revealed evidence of diet ontogeny in warmouth and potential competition for prey items among gape-matched individuals. Bioenergetics modeling revealed high levels of macroinvertebrate comsumption by these species relative to macroinvertebrate reproductive output suggesting that when combined with other sources of mortality, consumptive pressures placed by sunfish on benthic macroinvertebrates may be quite large. / by Jacob Bransky. / Thesis (M.S.)--Florida Atlantic University, 2012. / Includes bibliography. / Mode of access: World Wide Web. / System requirements: Adobe Reader.
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Towards an Ecosystem Approach for Non-Target Reef Fishes: Habitat Uses and Population Dynamics of South Florida Parrotfishes (Perciformes: Scaridae)Molina-Ureña, Helena 14 May 2009 (has links)
The goal of this research was to develop statistically robust ecosystem-based approaches, while optimizing data acquisition on relatively unexploited fish species in South Florida reefs, i.e., parrotfishes, Family Scaridae, in Biscayne Bay (with seasonal roller frame beam trawl surveys, 1996-2000) and Florida Keys (with annual Reef Fish Visual Censuses, 1997-2001), by following these steps: (I) analysis of information gaps for the stocks, including systematics, biogeography, population dynamics, reproductive ecology, trophodynamics, habitat use, and fisheries dynamics of Western Atlantic parrotfishes; (II) determination of primary research objectives from prioritization in Step I; (III) determination of essential fish habitats, ontogenetic shifts, migrations, and reef-seagrass habitat, from integration of stratified sampling design for fisheries-independent surveys, habitat selection theory-based analyses, and length-based analyses; (IV) estimation of population dynamics and fisheries-specific parameters encompassing life history demographics from empirical data or comparisons to theoretical expectations adapted to local conditions; (V) simulation modeling of a realistic range of fishing scenarios and demographic characteristics to evaluate the efficacy of potential traditional fisheries and spatial management strategies; and (VI) application of sampling optimization procedures and fisheries ecology approaches. Four scarid species had an estimated combined abundance of ca. 36.8 x 106 individuals in the Florida Keys. Connectivity among seagrass beds, coral reefs and deep waters had three major patterns: seagrass dwellers, reef dwellers, with inshore-to-offshore ontogenetic , and a seagrass-reef connection, using Biscayne Bay as an important recruitment ground. Marine protected areas of the Florida Keys National Marine Sanctuary did not show effects on abundance, size composition or spatial distribution of any parrotfish studied. Simulations suggested relatively short longevities (5-10 years), moderate body growth curvature, high instantaneous natural mortality rates (0.3-0.6 y super minus one), and low annual survival rates (27-54%). Simulated estimates of fishing mortalities ranged from 0.3 to 0.6 y super minus one, indicating low levels of exploitation, but low Spawning Potential Ratios (SPR = 23.5-26%). Proposed potential exploitation based on a legal minimum size equal to their size at first maturity and fishing rates equal or below to their natural mortality should secure SPR values at 45-48%.
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Isotopic ecosystem studies in the KwaZulu-Natal Bight.De Lecea, Ander Martinez. 11 November 2013 (has links)
The study area, the KwaZulu-Natal Bight, is an oceanographically important area, which, regardless of having two of the most important fisheries off the east coast of South Africa, has received little research attention regarding its biological functioning. Until now chiefly oceanographic processes have been considered the drivers of this generally oligotrophic system. This study seeks to understand which of three important processes, a topographically induced oceanic upwelling cell near Richards Bay, a cyclonic eddy near Durban, or fluvial fluxes centred around the Thukela River, forces ecological functioning through their nutrient or organic matter input. The overall aim of the thesis is to understand the pelagic and benthic ecosystems of the Bight in terms of these drivers through the use of stable isotope (δ¹³C and δ¹⁵N) analyses of a range of biotic and abiotic samples. These were collected on board of a number of research cruises – forming predominantly part of the larger African Coelacanth Ecosystem Programme suite of studies – in the wet and dry seasons of 2010.
Isotopic analyses found distinctions between fluvial and oceanic particulate organic matter and indicate that upwelling was not occurring in either sampling season. Organic matter originating from the Thukela River did not play a significant role in the wet season, although it dominated the planktonic pelagic food web in the dry season. The organic matter of the most productive region in the Bight, the Middle Shelf, was of riverine origin in the dry season, but of indeterminate origin in the wet season when it may have been an artefact of an old upwelling event which had previously occurred to the north of the Bight. There is, however, some evidence suggesting that this organic matter may rather have been of riverine origin, with its δ¹³C signals subsequently having been modified by the diatom bloom occurring there.
In the demersal ecosystem, sediment isotopic data show organic matter to be well-mixed throughout the Bight in both seasons, with riverine organic matter dominating most of the Bight except its northern and southern edges, where oceanic organic matter increases in importance. Sediment organic matter (most likely via the macrobenthic biota) was deemed an important food source for demersal animals and omnivory an
important feeding strategy. Seasonal studies from 2008 to 2010 in the Thukela Bank area indicate that the demersal animals' stable isotope signatures responded to the seasonal isotopic changes in riverine organic matter, indicating the cross-seasonal importance of this food source to the demersal ecosystem.
Parallel methodological studies examined how routine isotopic sample handling procedures could have affected the results of the ecological studies. These studies suggest that i) effects of preservation/fixation methods and the use of dyes are species-dependant; ii) acidification has no effect on zooplankton isotopic signatures, and that iii) drying methods alone and interactively with multiple thawing and refreezing of samples affect the stable isotope values offish muscle tissues. Recommendations are made for further improvements in methodology and considerations to be taken when processing samples.
Overall, it is concluded that riverine input to the Bight has a more important biological role than previously thought, and that organic matter from this source is an important driver of ecosystems within the Bight throughout the year for the demersal and pelagic ecosystems. / Thesis (Ph.D.)-University of KwaZulu-Natal, Westville, 2012.
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Phytoplankton studies in the KwaZulu-Natal Bight.Omarjee, Aadila. January 2012 (has links)
The KwaZulu-Natal Bight is an important area along the South African east coast, stretching 160 km
north from Scottsburgh to St Lucia (Lutjeharms et al., 2000). The Bight is of interest to the region as
the area contains some distinct physical features, which are presumed to drive the ecological
functioning of the shelf ecosystem through their role in nutrient sources. These include the Tugela
River, the second largest river in South Africa in terms of outflow, and the Agulhas Current that forms
an outer border at the edge of the continental shelf.
Phytoplankton interacts with the majority of essential ecological networks and therefore greatly
influences marine ecosystems. To this end, it is necessary to understand their ecophysiological rate
processes – particularly those that are influenced by the dominant nutrient inputs to the Bight. The
overall aim of this project is therefore to provide an insight into the sources of nutrients driving
phytoplankton productivity in the Bight.
Synoptic surveys were conducted to provide an indication of the distribution of Total Suspended
Solids (TSS), Particulate Organic Matter (POM) and phytoplankton in the Bight, while focussed
experiments used stable isotopes to examine the rate processes involving C and N acquisition, as well
as sources of N available in the surface water.
Concentration of particulate organic phosphorus and nitrogen were found to be higher in the wet
season when compared to the dry season. During the wet season a large variation in chlorophyll-a
fluorescence was observed across the Bight, while natural abundance isotope data indicated a seasonal
change in the nutrient source available. For the wet season nutrient concentration varied with site and
depth, however uptake rates (μg N.1ˉ¹.hˉ¹) measured using ¹⁵N tracer additions were not significantly
different with site and depth. Alternatively, the dry season showed a significant difference between
site in surface waters. In the wet season the mid shelf area had the highest uptake rate and
phytoplankton biomass while the Richards Bay north site dominated, with regard to the previously
mentioned factors, in the dry season. At the time of the experiments, neither the Durban eddy nor the
upwelling cell were present, and hypotheses regarding the importance of these physical features in
driving phytoplankton nutrient acquisition could not be assessed. However, a notable difference in
uptake rate between the wet and dry seasons was observed, and this difference is likely due to the
fluvial sources of nutrients from the Tugela and many other rivers entering the KZN coast, which are
absent during the dry season.
The results indicate that terrestrial nutrient sources play a major role in influencing nutrient
concentrations on the Bight, and hence influence the nearshore ecosystem of the region. / Thesis (M.Sc.)-University of KwaZulu-Natal, Westville, 2012.
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Assessment of effects of chemical contaminants in dredged material on marine ecosystems and human healthSchipper, Cornelis Anton, January 1900 (has links)
Published as the author's thesis (doctor, Wageningen University, 2009). / Vita. Includes bibliographical references (p. 125-138). Includes list of author's publications (p. 147-149).
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Assessment of effects of chemical contaminants in dredged material on marine ecosystems and human healthSchipper, Cornelis Anton, January 1900 (has links)
Published as the author's thesis (doctor, Wageningen University, 2009). / Includes bibliographical references (p. 125-138). Includes list of author's publications (p. 147-149).
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