15,034 research outputs found

    A prioritization protocol for coastal wetland restoration on Molokaʻi, Hawaiʻi

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    Hawaiian coastal wetlands provide important habitat for federally endangered waterbirds and socio-cultural resources for Native Hawaiians. Currently, Hawaiian coastal wetlands are degraded by development, sedimentation, and invasive species and, thus, require restoration. Little is known about their original structure and function due to the large-scale alteration of the lowland landscape since European contact. Here, we used 1) rapid field assessments of hydrology, vegetation, soils, and birds, 2) a comprehensive analysis of endangered bird habitat value, 3) site spatial characteristics, 4) sea-level rise projections for 2050 and 2100 and wetland migration potential, and 5) preferences of the Native Hawaiian community in a GIS site suitability analysis to prioritize restoration of coastal wetlands on the island of Molokaʻi. The site suitability analysis is the first, to our knowledge, to incorporate community preferences, habitat criteria for endangered waterbirds, and sea-level rise into prioritizing wetland sites for restoration. The rapid assessments showed that groundwater is a ubiquitous water source for coastal wetlands. A groundwater-fed, freshwater herbaceous peatland or “coastal fen” not previously described in Hawaiʻi was found adjacent to the coastline at a site being used to grow taro, a staple crop for Native Hawaiians. In traditional ecological knowledge, such a groundwater-fed, agro-ecological system is referred to as a loʻipūnāwai (spring pond). Overall, 39 plant species were found at the 12 sites; 26 of these were wetland species and 11 were native. Soil texture in the wetlands ranged from loamy sands to silt and silty clays and the mean % organic carbon content was 10.93% ± 12.24 (sd). In total, 79 federally endangered waterbirds, 13 Hawaiian coots (‘alae keʻokeʻo; Fulica alai) and 66 Hawaiian stilts (aeʻo; Himantopus mexicanus knudseni), were counted during the rapid field assessments. The site suitability analysis consistently ranked three sites the highest, Kaupapaloʻi o Kaʻamola, Kakahaiʻa National Wildlife Refuge, and ʻŌhiʻapilo Pond, under three different weighting approaches. Site prioritization represents both an actionable plan for coastal wetland restoration and an alternative protocol for restoration decision-making in places such as Hawaiʻi where no pristine “reference” sites exist for comparison

    Responding to the global challenges of ‘Too Much, Too Little and Too Dirty’ Water: Towards a Safer and More Just Water Future

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    The world water crisis is manifest through ‘Too Much, Too Little and Too Dirty’ water at multiple scales from the local to the global. Understanding the key drivers and consequences of this water crisis, and who bears the biggest costs, is necessary to develop appropriate responses, at scale and over time. Using four framings: one, water stocks and limits; two, water rights and responsibilities; three, water values and prices; and four, green and grey water infrastructure, we review the challenges and possible responses. Using a water justice lens, we highlight the transitional and transformational pathways towards a safer and more just water future

    Irish Ocean Climate and Ecosystem Status Report

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    Summary report for Irish Ocean Climate & Ecosystem Status Report also published here. This Irish Ocean Climate & Ecosystem Status Summary for Policymakers brings together the latest evidence of ocean change in Irish waters. The report is intended to summarise the current trends in atmospheric patterns, ocean warming, sea level rise, ocean acidification, plankton and fish distributions and abundance, and seabird population trends. The report represents a collaboration between marine researchers within the Marine Institute and others based in Ireland’s higher education institutes and public bodies. It includes authors from Met Éireann, Maynooth University, the University of Galway, the Atlantic Technological University, National Parks and Wildlife, Birdwatch Ireland, Trinity College Dublin, University College Dublin, Inland Fisheries Ireland, The National Water Forum, the Environmental Protection Agency, and the Dundalk Institute of Technology.This report is intended to summarise the current trends in Ireland’s ocean climate. Use has been made of archived marine data held by a range of organisations to elucidate some of the key trends observed in phenomena such as atmospheric changes, ocean warming, sea level rise, acidification, plankton and fish distributions and abundance, and seabirds. The report aims to summarise the key findings and recommendations in each of these areas as a guide to climate adaptation policy and for the public. It builds on the previous Ocean Climate & Ecosystem Status Report published in 2010. The report examines the recently published literature in each of the topic areas and combines this in many cases with analysis of new data sets including long-term time series to identify trends in essential ocean variables in Irish waters. In some cases, model projections of the likely future state of the atmosphere and ocean are presented under different climate emission scenarios.Marine Institut

    Optimising water quality outcomes for complex water resource systems and water grids

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    As the world progresses, water resources are likely to be subjected to much greater pressures than in the past. Even though the principal water problem revolves around inadequate and uncertain water supplies, water quality management plays an equally important role. Availability of good quality water is paramount to sustainability of human population as well as the environment. Achieving water quality and quantity objectives can be conflicting and becomes more complicated with challenges like, climate change, growing populations and changed land uses. Managing adequate water quality in a reservoir gets complicated by multiple inflows with different water quality levels often resulting in poor water quality. Hence, it is fundamental to approach this issue in a more systematic, comprehensive, and coordinated fashion. Most previous studies related to water resources management focused on water quantity and considered water quality separately. However, this research study focused on considering water quantity and quality objectives simultaneously in a single model to explore and understand the relationship between them in a reservoir system. A case study area was identified in Western Victoria, Australia with water quantity and quality challenges. Taylors Lake of Grampians System in Victoria, Australia receives water from multiple sources of differing quality and quantity and has the abovesaid problems. A combined simulation and optimisation approach was adopted to carry out the analysis. A multi-objective optimisation approach was applied to achieve optimal water availability and quality in the storage. The multi-objective optimisation model included three objective functions which were: water volume and two water quality parameters: salinity and turbidity. Results showed competing nature of water quantity and quality objectives and established the trade-offs. It further showed that it was possible to generate a range of optimal solutions to effectively manage those trade-offs. The trade-off analysis explored and informed that selective harvesting of inflows is effective to improve water quality in storage. However, with strict water quality restriction there is a considerable loss in water volume. The robustness of the optimisation approach used in this study was confirmed through sensitivity and uncertainty analysis. The research work also incorporated various spatio-temporal scenario analyses to systematically articulate long-term and short-term operational planning strategies. Operational decisions around possible harvesting regimes while achieving optimal water quantity and quality and meeting all water demands were established. The climate change analysis revealed that optimal management of water quantity and quality in storage became extremely challenging under future climate projections. The high reduction in storage volume in the future will lead to several challenges such as water supply shortfall and inability to undertake selective harvesting due to reduced water quality levels. In this context, selective harvesting of inflows based on water quality will no longer be an option to manage water quantity and quality optimally in storage. Some significant conclusions of this research work included the establishment of trade-offs between water quality and quantity objectives particular to this configuration of water supply system. The work demonstrated that selective harvesting of inflows will improve the stored water quality, and this finding along with the approach used is a significant contribution to decision makers working within the water sector. The simulation-optimisation approach is very effective in providing a range of optimal solutions, which can be used to make more informed decisions around achieving optimal water quality and quantity in storage. It was further demonstrated that there are range of planning periods, both long-term (>10 years) and short-term (<1 year), all of which offer distinct advantages and provides useful insights, making this an additional key contribution of the work. Importantly, climate change was also considered where it was found that diminishing water resources, particularly to this geographic location, makes it increasingly difficult to optimise both quality and quantity in storage providing further useful insights from this work.Doctor of Philosoph

    Characterizing the epidemiology of ophidiomycosis in North American snakes through field studies, modeling, pathogen genomic analysis, and treatment trials

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    The enormous impacts of human activities on global ecosystems pose a threat to the health of people, animals, and the environment. It is critical to study wildlife diseases in order to protect global biodiversity and promote global health, as notably highlighted by the effects on society during the COVID-19 pandemic. Emerging fungal diseases have profound impacts on people, agricultural crops, domestic animals, and wildlife. Ophidiomycosis, caused by the keratinophilic fungus Ophidiomyces ophidiicola, is an emerging infectious disease of wild and managed snakes worldwide. All snake species appear to be susceptible and it is a particular threat to species of conservation concern. The purpose of this dissertation was to address the gaps in current knowledge of ophidiomycosis in the United States, including the full range of snake species and geographic areas impacted by the disease, how disease and pathogen prevalence vary based on host and environmental factors, the impact of O. ophidiicola genomic diversity on disease epidemiology, and the effectiveness of specific treatment options. The specific objectives were to use fieldwork, clinical trials, molecular approaches, and statistical modeling to examine host, agent, and environmental factors that impact development of disease and characterize the pharmacodynamic and pharmacokinetic profiles for a single medication and delivery system in diseased snakes. Ophidiomycosis surveillance was conducted in a variety of snake species in southeast Georgia, USA and in Lake Erie watersnakes (Nerodia sipedon insularum, LEWS) in Ottawa and Erie Counties, Ohio, USA. Snakes were captured during visual encounter surveys and visually inspected for skin lesions suggestive of ophidiomycosis, then a body swab was collected to detect the presence of O. ophidiicola using qPCR. Each snake was assigned to an ophidiomycosis category based on the presence of skin lesions and O. ophidiicola. Logistic regression models were used to predict lesion presence, O. ophidiicola detection, and ophidiomycosis category based on individual, spatial, and temporal factors. For LEWS, models were also used to test for associations between lesion and fungal presence and a variety of climate, demographic, and environmental factors. Next, a multiplex qPCR-based genotyping assay was designed to differentiate between clades of O. ophidiicola, which were defined based on whole-genome sequencing conducted at the National Wildlife Health Center. Primer-probes sets were designed to target conserved and divergent areas between clade-representative genomes, such that each clade had a specific amplification pattern. Using the Fluidigm Access Array to conduct multiplex qPCR, the amplification pattern of a particular O. ophidiicola DNA sample across these primer-probes was used to assign it to a clade. This approach was validated using samples of known clade and applied to swab-extracted O. ophidiicola DNA samples from multiple snake species, states, and years. Multinomial logistic regression modeling was used to predict clade based on snake taxonomic group, state of origin, and year of collection. Finally, a controlled clinical trial was conducted using terbinafine nebulization to treat wild-caught Lake Erie watersnakes with natural ophidiomycosis. Snakes received terbinafine nebulization, saline nebulization, or no treatment, and response to treatment was measured using physical exams to document clinical disease severity, as well as qPCR of body and lesion swabs to measure O. ophidiicola quantity. Mixed models were used to analyze response to treatment based on initial disease severity, treatment group, year of the study, and length of treatment. Plasma and skin concentrations of terbinafine were measured using high-performance liquid chromatography (HPLC). A total of 786 free-ranging snakes representing 34 species and four families were examined and sampled in southeast Georgia. Of these, 27.5% had skin lesions and 13.3% were positive for O. ophidiicola DNA. This was the first report of O. ophidiicola in five of the 22 species that were qPCR positive and multinomial logistic regression modeling indicated that eastern indigo snakes (Drymarchon couperi) had a higher relative risk of apparent ophidiomycosis (lesions present and qPCR positive). The best models predicting qPCR result and ophidiomycosis category included individual factors and excluded temporal and spatial factors. A total of 837 Lake Erie watersnakes were evaluated across five surveillance sites between 2017 and 2020. The prevalence and odds of skin lesion presence, qPCR detection of O. ophidiicola, and ophidiomycosis categories varied between sites and years. Snakes were more likely to have skin lesions at lower temperatures and O. ophidiicola was more likely to be detected in snakes at sites with open space development and low-intensity development. The presence of emerging herbaceous wetlands, urban land change, and certain soil types increased the odds of both lesion presence and qPCR detection of O. ophidiicola. The multiplex qPCR-based genotyping assay consisted of 11 primer-probe sets and, compared to full-genome sequencing, correctly assigned 77.3% of the samples with known clade (Cohen’s kappa = 0.682, 95% CI: 0.527 – 0.837). Swab-extracted O. ophidiicola DNA samples from across the United States were assigned to five different clades, including three of the six pre-established clades and two newly defined clades, which likely represent recombinant strains of O. ophidiicola. U.S.state of collection was the only significant predictor of clade in multinomial logistic regression models and clade was not associated with disease severity in LEWS. Finally, terbinafine nebulization resulted in external molecular resolution of disease in 29.2% of treated snakes following three to six months of daily nebulization, compared to 5% of snakes receiving saline nebulization and 11.1% of snakes receiving no treatment. Terbinafine nebulization did not significantly decrease clinical disease, as measured by disease severity scores, but significantly reduced fungal quantity after three or more 30-day courses of treatment. Daily terbinafine nebulization was found to produce concentrations above the minimum inhibitory concentration for O. ophidiicola in both plasma and skin. This treatment may be most useful in snakes from managed populations that can be treated for several months, rather than wild snakes who are not releasable after multiple months in captivity. This work provides a great deal of new information about the epidemiology of ophidiomycosis, but many questions remain. Additional work to improve surveillance, conduct experimental infection trials, and use molecular techniques to evaluate host and pathogen gene expression will support snake health and conservation, as well as informing the management of emerging fungal diseases affecting wildlife, humans, and domestic animals.U of I OnlyAuthor requested U of Illinois access only (OA after 2yrs) in Vireo ETD syste

    Water security in Iraq

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    An Introduction to the Chalk Aquifers of Northern Europe

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    We briefly outline the progressive development of approaches to both the characterization and simulation of the hydrogeology of northern European chalk aquifers, which were some of the first in the world to be studied. The volume's scope includes work on water resources and quality, chalk streams and wetland ecosystems, chalks as heat reservoirs for building temperature regulation, sources of groundwater flood risk and impacts of engineering on the subsurface, and diffuse and point-source pollution affecting these aquifers. It excludes hydrocarbon-related studies and those focused on offshore chalk sequences. We briefly outline the current state of knowledge of hydrogeological processes, characterization, assessment and modelling, and the increasingly recognized importance of karst features. The latter were little discussed 20 years ago and are still often neglected. There follows a brief quantitative analysis of publication topics relating to chalk hydrogeology in the scientific literature over the past three decades, which highlights key trends including both the purposes of studies and the methods employed. We present a summary of the topics and contributions within this volume, and conclude by identifying the key issues that need to be addressed in order to ensure the sustainability of our chalk aquifers for the future

    Redrawing the hydrosocial cycle through treated wastewater reuse in the Metropolitan Region of Barcelon

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    : Increasing economic, social and environmental limits to the development of conventional water supply sources have shifted water resource frontiers to alternative sources, most notably desalination and wastewater reuse. In the past few years, critical scholarship has been prolific in its exploration of how desalination may redraw the hydrosocial cycle in different geographies; wastewater reuse, however, has received much less attention. In this article, we aim to contribute to a critical exploration of the implications of different types of wastewater reuse for urban purposes. We do so through an examination of the case of the Metropolitan Area of Barcelona (AMB), an\ud area with a fragile water supply system that has been undergoing a harsh drought in 2022/2023. We examine two examples of how treated wastewater may enter the residential sphere. The first involves the reuse of greywater for toilet flushing in residential buildings. The second is linked to the possibilities that advanced treatment of wastewater open up in terms of making urban water systems more robust and more resilient to recurring droughts; this advanced strategy enables both the bolstering of indirect reuse of reclaimed water for potable purposes and direct reuse through the development of dual networks of supply in new urban areas. In this paper, we attempt to unravel the different economic, social, environmental and political implications of those interventions through the lens of the hydrosocial cycle and resource frontiers. We triangulate a critical review of policy documents with informal conversations with policymakers and, in one of the case studies, previous research

    The Roles of Tidal Marshes in the Estuarine Biochemical Processes: A Numerical Modeling Study

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    Observations suggest that the existence of tidal marsh can alter the oxygen and nutrient dynamics in adjacent water bodies, but assessing the impacts of large tidal marshes on an estuary is challenging. In this study, we use a modeling approach to investigate the roles of tidal marshes on the estuarine biochemical processes. The marsh model, which simulates the ecological functions of marshes at seasonal and annual time-scales, is embedded inside an unstructured-grid three-dimensional hydrodynamic and eutrophication model (SCHISM-ICM). This modeling system simulates the growth and metabolism of the tidal marshes and links biological processes to nutrient dynamics in the water column and sediment. This model dynamically simulates nutrient recycling and physical transport of the materials between marshes and open water through wetting-drying processes. This coupled model system is validated and successfully applied to the York River Estuary. Model results suggest that tidal marshes influence the local diurnal dissolved oxygen (DO) cycle by exporting dissolved organic carbon and high sediment oxygen demand in the marsh system through the tidal exchange. The high deposition rates of organics and diurnal DO cycle enhance the sediment release of phosphorus. On the other hand, marshes tend to decrease dissolved inorganic nitrogen in the water column by settling particulate nutrients and enhancing the denitrification process. The study demonstrates that tidal marshes exert substantial impacts on the estuarine biochemical processes. The developed tidal marsh model enhances eutrophication modeling and advances the understanding of the feedback effects between marsh biogeochemistry and estuarine eutrophication processes on a systemic scale
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