15 research outputs found

    Coastal upwelling in the Rias Bajas, NW Spain: Contrasting the benthic regimes of the Rias de Arosa and de Muros

    Get PDF
    Nutrient-rich North Atlantic water upwells off the NW coast of Spain and intermittently intrudes into the rias, coastal embayments, by displacement during periods of offshore winds. High primary production associated with the upwelling supports an intensive raft culture of the edible mussel, Mytilus edulis. This culture is most intensive (ca. 2000 rafts) in the Ria de Arosa, and results in one of the highest protein yields per unit area on earth...

    Stoichiometry of the degradation of dissolved and particulate biogenic organic matter in the NW Iberian upwelling

    Get PDF
    The average composition of the dissolved and particulate products of early degradation of marine phytoplankton has been established for the first time in a coastal upwelling system using a mixing analysis along isopycnal surfaces combined with a stoichiometric model. About 17–18% of the mineralized organic matter is derived from the decomposition of organic particulates, and 16–35% is from the dissolved organic matter. The remaining 50–70% is derived probably from large fast sinking particles. On average, the mineralized material on large particles has the closest composition to the Redfield formula. The ratio of dissolved saccharides to dissolved organic matter respiration is >40% higher than expected from a material of Redfield composition. Finally, the ratio of lipid to particulate organic matter respiration is >80% larger than expected from a material of Redfield composition. Regarding the decomposition of hard structures, biogenic silica dissolves predominantly in the inner shelf, where organic carbon oxidation is more intense, and diatom deposition occurs preferentially

    Characterizing the role benthos plays in large coastal seas and estuaries: A modular approach

    No full text
    Ecologists studying coastal and estuarine benthic communities have long taken a macroecological view, by relating benthic community patterns to environmental factors across several spatial scales. Although many general ecological patterns have been established, often a significant amount of the spatial and temporal variation in soft-sediment communities within and among systems remains unexplained. Here we propose a framework that may aid in unraveling the complex influence of environmental factors associated with the different components of coastal systems (i.e. the terrestrial and benthic landscapes, and the hydrological seascape) on benthic communities, and use this information to assess the role played by benthos in coastal ecosystems. A primary component of the approach is the recognition of system modules (e.g. marshes, dendritic systems, tidal rivers, enclosed basins, open bays, lagoons). The modules may differentially interact with key forcing functions (e.g. temperature, salinity, currents) that influence system processes and in turn benthic responses and functions. Modules may also constrain benthic characteristics and related processes within certain ecological boundaries and help explain their overall spatio-temporal variation. We present an example of how benthic community characteristics are related to the modular structure of 14 coastal seas and estuaries, and show that benthic functional group composition is significantly related to the modular structure of these systems. We also propose a framework for exploring the role of benthic communities in coastal systems using this modular approach and offer predictions of how benthic communities may vary depending on the modular composition and characteristics of a coastal system

    A novel lumen-apposing metal stent for endoscopic ultrasound-guided drainage of pancreatic fluid collections: a prospective cohort study

    No full text
    BACKGROUND AND STUDY AIMS: A novel large-diameter, lumen-apposing, self-expanding metal stent with bilateral flanges was recently developed for endoscopic ultrasound (EUS)-guided transmural drainage of symptomatic pancreatic fluid collections (PFCs). The aim of this study was to evaluate the efficacy and safety of this stent in a large cohort. PATIENTS AND METHODS: Patients with a PFC undergoing EUS-guided drainage with this novel stent were prospectively enrolled in this multicenter cohort study. RESULTS: There were 61 patients: 46 patients (75 %) with walled-off necrosis (WON) and 15 (25 %) with a pancreatic pseudocyst. Stent placement was technically successful in 60 patients (98 %, 95 %CI 95 % - 100 %). Clinical success, defined as resolution of clinical symptoms in combination with a decrease in the PFC size to </= 2 cm on imaging, was achieved in 93 % of patients with a pancreatic pseudocyst (95 %CI 77 % - 100 %) and in 81 % of patients with WON (95 %CI 69 % - 94 %). Treatment failure occurred in nine patients (16 %, 95 %CI 6 % - 26 %), including four patients who required surgical intervention. Stent removal was performed in 82 % of patients after a median of 32 days (range 2 - 178) and was rated as easy in all but one patient. In 10 patients, endoscopic stent removal was not performed because of stent migration (n = 3), stent dislodgement during necrosectomy (n = 3), stent removal during surgery (n = 2), or refusal by the patient (n = 2). In total, five major complications were reported (9 %, 95 %CI 2 % - 16 %), including PFC infection (n = 4) and perforation (n = 1). CONCLUSION: EUS-guided drainage using this novel stent is feasible and the clinical results obtained are promising with a low major complication rate
    corecore