47 research outputs found

    Environmental foundations of typhoid fever in the Fijian residential setting

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    Proximal characteristics and conditions in the residential setting deserve greater attention for their potential to influence typhoid transmission. Using a case-control design in Central Division, Republic of Fiji, we examined bacterial (coliform and Escherichia coli) contamination and chemical composition of water and soil as potential vehicles of exposure to Salmonella Typhi, combining observational analysis of residential living conditions, geospatial analysis of household locations, and factor analysis to explore multivariate associations with the risk of developing typhoid fever. Factors positively associated with typhoid infection related to drainage [phosphate (OR 4.235, p = 0.042) and E. coli concentrations (OR 2.248, p = 0.029) in toilet drainage soil, housing [external condition (OR 3.712, p \u3c 0.001)], drinking water contamination (OR 2.732, p = 0.003) and sanitary condition (OR 1.973, p = 0.031). These five factors explained 42.5% of the cumulative variance and were significant in predicting typhoid infection. Our results support the hypothesis that a combination of spatial and biophysical attributes of the residential setting influence the probability of typhoid transmission; in this study, factors associated with poor drainage, flooding, and sanitary condition increase local exposure to contaminated water and soil, and thereby infection. These findings extend testing of causal assumptions beyond the immediate domestic domain, enhance the scope of traditional case control epidemiology and allow greater specificity of interventions at the scale of the residential setting

    Diversification of refugia types needed to secure the future of coral reefs subject to climate change

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    Identifying locations of refugia from the thermal stresses of climate change for coral reefs and better managing them is one of the key recommendations for climate change adaptation. We review and summarize approximately 30 years of applied research focused on identifying climate refugia to prioritize the conservation actions for coral reefs under rapid climate change. We found that currently proposed climate refugia and the locations predicted to avoid future coral losses are highly reliant on excess heat metrics, such as degree heating weeks. However, many existing alternative environmental, ecological, and life-history variables could be used to identify other types of refugia that lead to the desired diversified portfolio for coral reef conservation. To improve conservation priorities for coral reefs, there is a need to evaluate and validate the predictions of climate refugia with long-term field data on coral abundance, diversity, and functioning. There is also the need to identify and safeguard locations displaying resistance toprolonged exposure to heat waves and the ability to recover quickly after thermal exposure. We recommend using more metrics to identify a portfolio of potential refugia sites for coral reefs that can avoid, resist, and recover from exposure to high ocean temperatures and the consequences of climate change, thereby shifting past efforts focused on avoidance to a diversified risk-spreading portfolio that can be used to improve strategic coral reef conservation in a rapidly warming climate

    Community change within a Caribbean coral reef Marine Protected Area following two decades of local management

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    © The Author(s), 2013. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in PLoS ONE 8 (2013): e54069, doi:10.1371/journal.pone.0054069.Structural change in both the habitat and reef-associated fish assemblages within spatially managed coral reefs can provide key insights into the benefits and limitations of Marine Protected Areas (MPAs). While MPA zoning effects on particular target species are well reported, we are yet to fully resolve the various affects of spatial management on the structure of coral reef communities over decadal time scales. Here, we document mixed affects of MPA zoning on fish density, biomass and species richness over the 21 years since establishment of the Saba Marine Park (SMP). Although we found significantly greater biomass and species richness of reef-associated fishes within shallow habitats (5 meters depth) closed to fishing, this did not hold for deeper (15 m) habitats, and there was a widespread decline (38% decrease) in live hard coral cover and a 68% loss of carnivorous reef fishes across all zones of the SMP from the 1990s to 2008. Given the importance of live coral for the maintenance and replenishment of reef fishes, and the likely role of chronic disturbance in driving coral decline across the region, we explore how local spatial management can help protect coral reef ecosystems within the context of large-scale environmental pressures and disturbances outside the purview of local MPA management.Funding was provided by the Saba Conservation Foundation ((SCF), King Abdullah University of Science and Technology, The Australian National University and Australian Research Council

    Blue justice: A review of emerging scholarship and resistance movements

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    This is the final version. Available from Cambridge University Press via the DOI in this record. The term “blue justice” was coined in 2018 during the 3rd World Small-Scale Fisheries Congress. Since then, academic engagement with the concept has grown rapidly. This article reviews 5 years of blue justice scholarship and synthesizes some of the key perspectives, developments, and gaps. We then connect this literature to wider relevant debates by reviewing two key areas of research – first on blue injustices and second on grassroots resistance to these injustices. Much of the early scholarship on blue justice focused on injustices experienced by small-scale fishers in the context of the blue economy. In contrast, more recent writing and the empirical cases reviewed here suggest that intersecting forms of oppression render certain coastal individuals and groups vulnerable to blue injustices. These developments signal an expansion of the blue justice literature to a broader set of affected groups and underlying causes of injustice. Our review also suggests that while grassroots resistance efforts led by coastal communities have successfully stopped unfair exposure to environmental harms, preserved their livelihoods and ways of life, defended their culture and customary rights, renegotiated power distributions, and proposed alternative futures, these efforts have been underemphasized in the blue justice scholarship, and from marine and coastal literature more broadly. We conclude with some suggestions for understanding and supporting blue justice now and into the future.French Foundation for Research on Biodiversity (FRB

    Nutrient Enrichment Increases Mortality of Mangroves

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    Nutrient enrichment of the coastal zone places intense pressure on marine communities. Previous studies have shown that growth of intertidal mangrove forests is accelerated with enhanced nutrient availability. However, nutrient enrichment favours growth of shoots relative to roots, thus enhancing growth rates but increasing vulnerability to environmental stresses that adversely affect plant water relations. Two such stresses are high salinity and low humidity, both of which require greater investment in roots to meet the demands for water by the shoots. Here we present data from a global network of sites that documents enhanced mortality of mangroves with experimental nutrient enrichment at sites where high sediment salinity was coincident with low rainfall and low humidity. Thus the benefits of increased mangrove growth in response to coastal eutrophication is offset by the costs of decreased resilience due to mortality during drought, with mortality increasing with soil water salinity along climatic gradients

    Drivers of reef shark abundance and biomass in the Solomon Islands

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    Remote island nations face a number of challenges in addressing concerns about shark population status, including access to rigorously collected data and resources to manage fisheries. At present, very little data are available on shark populations in the Solomon Islands and scientific surveys to document shark and ray diversity and distribution have not been completed. We aimed to provide a baseline of the relative abundance and diversity of reef sharks and rays and assess the major drivers of reef shark abundance/biomass in the Western Province of the Solomon Islands using stereo baited remote underwater video. On average reef sharks were more abundant than in surrounding countries such as Fiji and Indonesia, yet below that of remote islands without historical fishing pressure, suggesting populations are relatively healthy but not pristine. We also assessed the influence of location, habitat type/complexity, depth and prey biomass on reef shark abundance and biomass. Location was the most important factor driving reef shark abundance and biomass with two times the abundance and a 43% greater biomass of reef sharks in the more remote locations, suggesting fishing may be impacting sharks in some areas. Our results give a much needed baseline and suggest that reef shark populations are still relatively unexploited, providing an opportunity for improved management of sharks and rays in the Solomon Islands

    The nature and extent of evidence on methodologies for monitoring and evaluating marine spatial management measures in the UK and similar coastal waters : a systematic map

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    Background: Anthropogenic degradation of marine ecosystems is widely accepted as a major social-ecological problem. The growing urgency to manage marine ecosystems more effectively has led to increasing application of spatial management measures (marine protected areas [MPAs], sectoral [e.g. fishery] closures and marine spatial planning [marine plans]). Understanding the methodologies used to evaluate the effectiveness of these measures against social, economic, and ecological outcomes is key for designing effective monitoring and evaluation programmes. Methods: We used a pre-defined and tested search string focusing on intervention and outcome terms to search for relevant studies across four bibliographic databases, Google Scholar, 39 organisational websites, and one specialist data repository. Searches were conducted in English and restricted to the period 2009 to 2019 to align with current UK marine policy contexts. Relevant studies were restricted to UK-relevant coastal countries, as identified by key stakeholders. Search results were screened for relevance against pre-defined eligibility criteria first at title and abstract level, and then at full text. Articles assessed as not relevant at full text were recorded with reasons for exclusion. Two systematic map databases of meta-data and coded data from relevant primary and secondary studies, respectively, were produced. Review findings: Over 19,500 search results were identified, resulting in 391 relevant primary articles, 33 secondary articles and 49 tertiary reviews. Relevant primary articles evaluated spatial management measures across a total of 22 social, economic and ecological outcomes; only 2.8% considered all three disciplines, with most focused exclusively on ecological (67.8%) or social (13.3%) evaluations. Secondary articles predominately focused on ecological evaluations (75.8%). The majority of the primary and secondary evidence base aimed to evaluate the effectiveness of MPAs (85.7% and 90.9% respectively), followed by fisheries closures (12.5%; 3.0%) with only 1.8% of primary, and 6.1% of secondary, articles focused on marine plans or on MPAs and fisheries closures combined. Most evaluations reported within primary articles were conducted for a single site (60.4%) or multiple individual sites (32.5%), with few evaluating networks of sites (6.9%). Secondary articles mostly evaluated multiple individual sites (93.9%). Most (70.3%) primary articles conducted principal evaluations, i.e. basic description of effects; 29.4% explored causation; and 0.3% undertook benefit evaluations. Secondary articles predominately explored causation (66.7%) with the remainder conducting principal evaluations. Australia (27.4%), the USA (18.4%) and the UK (11.3%) were most frequently studied by primary articles, with secondary articles reporting mostly global (66.7%) or European (18.2%) syntheses. Conclusions: The systematic map reveals substantial bodies of evidence relating to methods of evaluating MPAs against ecological outcomes. However, key knowledge gaps include evaluation across social and economic outcomes and of overall merit and/or worth (benefit evaluation), as well as of: marine plans; networks of sites; real-time, temporary or seasonal closures; spatial management within offshore waters, and lagoon or estuary environments. Although the evidence base has grown over the past two decades, information to develop comprehensive evaluation frameworks remains insufficient. Greater understanding on how to evaluate the effectiveness of spatial management measures is required to support improved management of global ocean resources and spaces

    Temporal Changes in Fluid Chemistry and Energy Profiles in the Vulcano Island Hydrothermal System

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    In June 2003, the geochemical composition of geothermal fluids was determined at 9 sites in the Vulcano hydrothermal system, including sediment seeps, geothermal wells, and submarine vents. Compositional data were combined with standard state reaction properties to determine the overall Gibbs free energy (deltaGr) for 120 potential lithotrophic and heterotrophic reactions. Lithotrophic reactions in the H-O-N-S-C-Fe system were considered, and exergonic reactions yielded up to 120 kJ per mole of electrons transferred. The potential for heterotrophy was characterized by energy yields from the complete oxidation of 6 carboxylic acids—formic, acetic, propanoic, lactic, pyruvic, and succinic—with the following redox pairs:O2/H2O, SO4 2-/H2S, NO3 -/NH4+, S0/H2S, and Fe3O4/Fe2+. Heterotrophic reactions yielded 6–111 kJ/mol e-. Energy yields from both lithotrophic and heterotrophic reactions were highly dependent on the terminal electron acceptor (TEA); reactions with O2 yielded the most energy, followed by those with NO3-, Fe(III), SO4 2-, and S0. When only reactions with complete TEA reduction were included, the exergonic lithotrophic reactions followed a similar electron tower. Spatial variability in deltaGr was significant for iron redox reactions, owing largely to the wide range in Fe2+ and H+ concentrations. Energy yields were compared to those obtained for samples collected in June 2001. The temporal variations in geochemical composition and energy yields observed in the Vulcano hydrothermal system between 2001 and 2003 were moderate. The largest differences in deltaGr over the 2 years were from iron redox reactions, due to temporal changes in the Fe2+ and H+ concentrations. The observed variations in fluid composition across the Vulcano hydrothermal system have the potential to influence not only microbial diversity but also the metabolic strategies of the resident microbial communities

    Environmental Foundations of Typhoid Fever in the Fijian Residential Setting

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    Proximal characteristics and conditions in the residential setting deserve greater attention for their potential to influence typhoid transmission. Using a case-control design in Central Division, Republic of Fiji, we examined bacterial (coliform and Escherichia coli) contamination and chemical composition of water and soil as potential vehicles of exposure to Salmonella Typhi, combining observational analysis of residential living conditions, geospatial analysis of household locations, and factor analysis to explore multivariate associations with the risk of developing typhoid fever. Factors positively associated with typhoid infection related to drainage [phosphate (OR 4.235, p = 0.042) and E. coli concentrations (OR 2.248, p = 0.029) in toilet drainage soil, housing [external condition (OR 3.712, p < 0.001)], drinking water contamination (OR 2.732, p = 0.003) and sanitary condition (OR 1.973, p = 0.031). These five factors explained 42.5% of the cumulative variance and were significant in predicting typhoid infection. Our results support the hypothesis that a combination of spatial and biophysical attributes of the residential setting influence the probability of typhoid transmission; in this study, factors associated with poor drainage, flooding, and sanitary condition increase local exposure to contaminated water and soil, and thereby infection. These findings extend testing of causal assumptions beyond the immediate domestic domain, enhance the scope of traditional case control epidemiology and allow greater specificity of interventions at the scale of the residential setting
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