42 research outputs found

    Modelling of essential fish habitat based on remote sensing, spatial analysis and GIS

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    We review the variety of existing modelling approaches applied to species habitat mapping and we discuss issues arising from the availability and nature of sampled biological data and corresponding ecological and environmental habitat descriptors, as well as the different spatial analysis approaches that are selected according to specific hypotheses. We focus on marine species habitat mapping, presenting an overview of work on modelling fish habitat carried out through a European Communities Policy-Support Action, EnviEFH 'Environmental Approach to Essential Fish Habitat (EFH) Designation' (2005-2008). The selection of the appropriate habitat model is dataset-specific and the resulting EFH maps are often similar in spite of using different models. Derived EFH maps are based on either environmental ranges (used as minimum and maximum environmental habitat descriptors) or probability of occurrence values. We apply model outputs to regions larger than sampled areas making use of the capacity of satellite data to cover wide areas. © 2008 Springer Science+Business Media B.V

    The application of predictive modelling for determining bio-environmental factors affecting the distribution of blackflies (Diptera: Simuliidae) in the Gilgel Gibe watershed in Southwest Ethiopia

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    Blackflies are important macroinvertebrate groups from a public health as well as ecological point of view. Determining the biological and environmental factors favouring or inhibiting the existence of blackflies could facilitate biomonitoring of rivers as well as control of disease vectors. The combined use of different predictive modelling techniques is known to improve identification of presence/absence and abundance of taxa in a given habitat. This approach enables better identification of the suitable habitat conditions or environmental constraints of a given taxon. Simuliidae larvae are important biological indicators as they are abundant in tropical aquatic ecosystems. Some of the blackfly groups are also important disease vectors in poor tropical countries. Our investigations aim to establish a combination of models able to identify the environmental factors and macroinvertebrate organisms that are favourable or inhibiting blackfly larvae existence in aquatic ecosystems. The models developed using macroinvertebrate predictors showed better performance than those based on environmental predictors. The identified environmental and macroinvertebrate parameters can be used to determine the distribution of blackflies, which in turn can help control river blindness in endemic tropical places. Through a combination of modelling techniques, a reliable method has been developed that explains environmental and biological relationships with the target organism, and, thus, can serve as a decision support tool for ecological management strategies

    Mesoscale productivity fronts and local fishing opportunities in the European Seas

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    This study evaluates the relationship between both commercial and scientific spatial fisheries data and a new satellite-based estimate of potential fish production (Ocean Productivity available to Fish, OPFish) in the European Seas. To construct OPFish, we used productivity frontal features derived from chlorophyll-a horizontal gradients, which characterize 10%–20% of the global phytoplankton production that effectively fuels higher trophic levels. OPFish is relatively consistent with the spatial distribution of both pelagic and demersal fish landings and catches per unit of effort (LPUEs and CPUEs, respectively). An index of harvest relative to ocean productivity (HP index) is calculated by dividing these LPUEs or CPUEs with OPFish. The HP index reflects the intensity of fishing by gear type with regard to local fish production. Low HP levels indicate lower LPUEs or CPUEs than expected from oceanic production, suggesting over-exploitation, while high HP levels imply more sustainable fishing. HP allows comparing the production-dependent suitability of local fishing intensities. Our results from bottom trawl data highlight that over-exploitation of demersal species from the shelves is twice as high in the Mediterranean Sea than in the North-East Atlantic. The estimate of HP index by dominant pelagic and demersal gears suggests that midwater and bottom otter trawls are associated with the lowest and highest overfishing, respectively. The contrasts of fishing intensity at local scales captured by the HP index suggest that accounting for the local potential fish production can promote fisheries sustainability in the context of ecosystem-based fisheries management as required by international marine policies

    Status of pelagic habitats within the EU-Marine Strategy Framework Directive: Proposals for improving consistency and representativeness of the assessment

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    Anthropogenic activities have transformed the pelagic habitat in the last decades with profound implications for its essential functions. While the EU-Marine Strategy Framework Directive 2008/56/EC and the Commission Decision (EU) 2017/848 have set criteria and methodological standards for the assessment and determination of Good Environmental Status (GES) for pelagic habitats in EU waters, there is strong evidence that Member States have not yet harmonized the pelagic GES assessment across EU marine waters. Today, pelagic habitats are assessed by evaluating whether good status is achieved by each of the pelagic indicators, but this approach fails to observe the high variability of the pelagic environment. To this end, GES is not estimated at pelagic habitats scale but only for each individual indicator. This paper synthesises the latest developments on pelagic habitats assessment and identifies the main factors limiting the consistency of the assessment across Member States: i) coarse spatial and temporal scales of sampling effort as regards to the pelagic habitat dynamics, ii) little consideration of the whole range of plankton (and, to some extent, of zooplankton) size and trophic spectra, iii) lack of integrated hydro-biogeochemical and biological studies and collaboration among experts from different scientific fields, iv) limited availability of pressure-based indicators, and v) lack of integration methods of the pelagic indicators’ status for the GES determination. This analysis demonstrates the importance of maintaining a consistent sampling frequency and a spatially extensive network of stations across the gradient of anthropogenic pressures, where spatial environmental data can help objectively extrapolating field data

    Priorities for Mediterranean marine turtle conservation and management in the face of climate change

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    As climate-related impacts threaten marine biodiversity globally, it is important to adjust conservation efforts to mitigate the effects of climate change. Translating scientific knowledge into practical management, however, is often complicated due to resource, economic and policy constraints, generating a knowledge-action gap. To develop potential solutions for marine turtle conservation, we explored the perceptions of key actors across 18 countries in the Mediterranean. These actors evaluated their perceived relative importance of 19 adaptation and mitigation measures that could safeguard marine turtles from climate change. Of importance, despite differences in expertise, experience and focal country, the perceptions of researchers and management practitioners largely converged with respect to prioritizing adaptation and mitigation measures. Climate change was considered to have the greatest impacts on offspring sex ratios and suitable nesting sites. The most viable adaptation/mitigation measures were considered to be reducing other pressures that act in parallel to climate change. Ecological effectiveness represented a key determinant for implementing proposed measures, followed by practical applicability, financial cost, and societal cost. This convergence in opinions across actors likely reflects long-standing initiatives in the Mediterranean region towards supporting knowledge exchange in marine turtle conservation. Our results provide important guidance on how to prioritize measures that incorporate climate change in decision-making processes related to the current and future management and protection of marine turtles at the ocean-basin scale, and could be used to guide decisions in other regions globally. Importantly, this study demonstrates a successful example of how interactive processes can be used to fill the knowledge-action gap between research and management.This work was conducted under FutureMares EU project that received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 869300. The Mediterranean Marine Turtle Working Group was established in 2017 and is continuously supported by MedPAN and the National Marine Park of Zakynthos. The work of AC was supported by the Hellenic Foundation for Research and Innovation (H.F.R.I.) under the “First Call for H.F.R.I. Research Projects to support Faculty members and Researchers and the procurement of high-cost research equipment grant” (Project Number: 2340).Peer reviewe

    Non-indigenous species refined national baseline inventories : A synthesis in the context of the European Union's Marine Strategy Framework Directive

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    Refined baseline inventories of non-indigenous species (NIS) are set per European Union Member State (MS), in the context of the Marine Strategy Framework Directive (MSFD). The inventories are based on the initial assessment of the MSFD (2012) and the updated data of the European Alien Species Information Network, in collaboration with NIS experts appointed by the MSs. The analysis revealed that a large number of NIS was not reported from the initial assessments. Moreover, several NIS initially listed are currently considered as native in Europe or were proven to be historical misreportings. The refined baseline inventories constitute a milestone for the MSFD Descriptor 2 implementation, providing an improved basis for reporting new NIS introductions, facilitating the MSFD D2 assessment. In addition, the inventories can help MSs in the establishment of monitoring systems of targeted NIS, and foster cooperation on monitoring of NIS across or within shared marine subregions. Highlights • Refined MSFD baseline inventories of non-indigenous species (NIS) are set in EU. • The inventories are given per EU Member State (MS) and MSFD subregion up to 2012. • The NIS lists provide a basis for reporting new NIS introductions in EU after 2012. • Our work constitutes a milestone for the MSFD Descriptor 2 implementation

    Non-indigenous species refined national baseline inventories: A synthesis in the context of the European Union's Marine Strategy Framework Directive

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    Refined baseline inventories of non-indigenous species (NIS) are set per European Union Member State (MS), in the context of the Marine Strategy Framework Directive (MSFD). The inventories are based on the initial assessment of the MSFD (2012) and the updated data of the European Alien Species Information Network, in collaboration with NIS experts appointed by the MSs. The analysis revealed that a large number of NIS was not reported from the initial assessments. Moreover, several NIS initially listed are currently considered as native in Europe or were proven to be historical misreportings. The refined baseline inventories constitute a milestone for the MSFD Descriptor 2 implementation, providing an improved basis for reporting new NIS introductions, facilitating the MSFD D2 assessment. In addition, the inventories can help MSs in the establishment of monitoring systems of targeted NIS, and foster cooperation on monitoring of NIS across or within shared marine subregions.Henn Ojaveer and Maiju Lehtiniemi wish to acknowledge the project COMPLETE (Completing management options in the Baltic Sea region to reduce risk of invasive species introduction by shipping), co-financed by the European Union's funding Programme Interreg Baltic Sea Region (European Regional Development Fund). João Canning-Clode was supported by a starting grant in the framework of the 2014 FCT Investigator Programme (IF/01606/2014/CP1230/CT0001) and wish to acknowledge the support of Fundação para a Ciência e Tecnologia (FCT), through the strategic project UID/MAR/04292/2019 granted to MARE

    The chlorophyll-a gradient as primary Earth observation index of marine ecosystem feeding capacity

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    An efficient ocean management for fisheries requires accurate data over large spatial scales. The horizontal gradient of chlorophyll-a (and the derived mesozooplankton habitat index) exemplifies a plankton-to-fish index in support of a sustainable ocean management that targets fisheries and ecosystem productivity. The gradient of chlorophyll-a, as expressing the productivity of fronts, showed to be active long enough to sustain the development of mesozooplankton and to attract predators. In the global ocean, the chlorophyll-a gradient characterizes about 10 to 20% of the phytoplankton productivity that is transferred along marine food chains. Despite the warming of the surface ocean over the period 2003-2019, the global area-averaged trend of frequency of chlorophyll-a gradients, which is associated to the mesozooplankton feeding habitat and fish productivity, appears to be slightly positive with, however, contrasted regional trends.Daily values of chlorophyll-a gradient can be computed at global scale for the last two decades as well as up to near real-time. This is critical to improve our understanding of the plankton-to-fish dynamics, especially under the current effects of climate change, and to build observation-based operational products that will inform the future spatial and dynamic ocean management. The computation of such gradient requires a specific expertise in ocean colour, making them difficult to obtain for non-specialists. Their operational availability could therefore offer a critical benefit to ecosystem modelers and marine biologists and, in turn, to regional fisheries management facing overexploitation and the effects of climate change. Marine policies such as the EU Common Fisheries Policy and the Marine Strategy Framework Directive will ultimately be efficiently supported by the use of chlorophyll-a gradient as a direct, observation-based, biological variable monitoring the marine ecosystem productivity across a wide range of spatial and temporal scales

    Revascularization of a single-kidney occluded stent for renal salvage complicated by guide wire distal artery perforation and reperfusion injury

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    Background: The complexity of the case, including the rarefied simultaneous occurrence of complications—iatrogenic, as well as reperfusion injury, invite reporting and publication. Case presentation: A 39-year-old woman with a single-functioning left kidney, previous left renal artery stenting (RAS), and known hypercoagulopathy was hospitalized for flash pulmonary edema, elevated serum creatinine (9.7 mg/dl), and refractory hypertension. She was subsequently referred to our center [2] for endovascular treatment of acute renal ischemia (AKI) due to RAS occlusion. Periprocedural complications of guide-wire arterial perforation and reperfusion injury resulted in life-threatening hemorrhage. Conclusions: Following more than 48 h of hypoperfusion of the left kidney, revascularization of the thrombosed RAS was successfully attempted with selective, trans-catheter thrombolysis, and balloon angioplasty. Ultra-selective, nephron-sparing coil embolization was successfully performed. The patient’s creatinine level decreased to 2.8 mg/dl at 12 days and to 1.5 mg/dl at 3 months. After 1 year of follow-up, the stent remains patent, and the patient is asymptomatic with stable renal function. © 2020, The Author(s)

    Percutaneous computed tomography-guided radiofrequency ablation of a spinal osteoid osteoma abutting the dura: a case report and review of the literature

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    PurposeOsteoid osteomas in the spine constitute a challenging group for both surgical and percutaneous approaches. Purpose of the present study is to report a case report of a spinal osteoid osteoma in a challenging spinal location and review literature for safety and efficacy of the technique.MethodsWe report a case of spinal osteoid osteoma extending in the epidural space and abutting the dura in a pediatric patient treated by percutaneous computed tomography-guided radiofrequency ablation. This is not a systematic review of the literature. A number of separate literature searches were performed. Non-English studies and case reports were excluded from the study. All references of the obtained articles were also evaluated for any additional information.ResultsAlthough all prophylactic measures were taken (hydrodissection, thermocouples and neurophysiologic monitoring) and the procedure was uneventful, patient within three hours, was unable to raise or bend the unilateral lower extremity below the knee. Pain reduction was significant from the first morning post-ablation and during the follow-up period of 18 months. MR scan was within normal limits. Dexamethasone was iv injected for 24 h and prescribed per os for 7 days. At follow-up 1 week later mobility of the lower extremity had returned to normal.ConclusionAs far as spine ablation is concerned, all prophylactic measures should be taken; neurophysiologic monitoring seems to be more sensitive than temperature measurement. Intravenous and per os corticosteroids are extremely useful in case of nerve damage
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