Predicting global habitat suitability for stony corals on seamounts

Aim Globally, species distribution patterns in the deep sea are poorly resolved, with spatial coverage being sparse for most taxa and true absence data missing. Increasing human impacts on deep-sea ecosystems mean that reaching a better understanding of such patterns is becoming more urgent. Cold-water stony corals (Order Scleractinia) form structurally complex habitats (dense thickets or reefs) that can support a diversity of other associated fauna. Despite their widely accepted ecological importance, records of scleractinian corals on seamounts are patchy and simply not available for most of the global ocean. The objective of this paper is to model the global distribution of suitable habitat for stony corals on seamounts. Location Seamounts worldwide. Methods We compiled a database containing all accessible records of scleractinian corals on seamounts. Two modelling approaches developed for presence-only data were used to predict global habitat suitability for seamount scleractinians: maximum entropy modelling (Maxent) and environmental niche factor analysis (ENFA). We generated habitat-suitability maps and used a cross-validation process with a threshold-independent metric to evaluate the performance of the models. Results Both models performed well in cross-validation, although the Maxent method consistently outperformed ENFA. Highly suitable habitat for seamount stony corals was predicted to occur at most modelled depths in the North Atlantic, and in a circumglobal strip in the Southern Hemisphere between 20° and 50° S and shallower than around 1500 m. Seamount summits in most other regions appeared much less likely to provide suitable habitat, except for small near-surface patches. The patterns of habitat suitability largely reflect current biogeographical knowledge. Environmental variables positively associated with high predicted habitat suitability included the aragonite saturation state, and oxygen saturation and concentration. By contrast, low levels of dissolved inorganic carbon, nitrate, phosphate and silicate were associated with high predicted suitability. High correlation among variables made assessing individual drivers difficult. Main conclusions Our models predict environmental conditions likely to play a role in determining large-scale scleractinian coral distributions on seamounts, and provide a baseline scenario on a global scale. These results present a first-order hypothesis that can be tested by further sampling. Given the high vulnerability of cold-water corals to human impacts, such predictions are crucial tools in developing worldwide conservation and management strategies for seamount ecosystems. © 2009 Blackwell Publishing Ltd

A retrospective and prospective 12-month observational study of the socioeconomic burden of moderate to severe irritable bowel syndrome with constipation in Spain

INTRODUCTION: The socioeconomic burden of irritable bowel syndrome with constipation (IBS-C) has never been formally assessed in Spain. PATIENTS AND METHODS: This 12-month (6-month retrospective and prospective periods) observational, multicentre study assessed the burden of moderate-to-severe IBS-C in Spain. Patients were included if they had been diagnosed with IBS-C (Rome III criteria) within the last 5 years and had moderate-to-severe IBS-C (IBS Symptom Severity Scale score [IBS-SSS] ≥175) at inclusion. The primary objective was to assess the direct cost to the Spanish healthcare system (HS). RESULTS: A total of 112 patients were included, 64 (57%) of which had severe IBS-C at inclusion. At baseline, 89 (80%) patients reported abdominal pain and distention. Patient quality of life (QoL), measured by the IBS-C QoL and EQ-5D instruments, was found to be impaired with a mean score of 59 and 57 (0-100, worst-best), respectively. Over the 6-month prospective period the mean IBS-C severity, measured using the IBS-SSS showed some improvement (315-234 [0-500, best-worst]). During the year, 89 (80%) patients used prescription drugs for IBS-C, with laxatives being the most frequently prescribed (n=70; 63%). The direct cost to the HS was €1067, and to the patient was €568 per year. The total direct cost for moderate-to-severe IBS-C was €1635. DISCUSSION: The majority of patients reported continuous IBS-C symptoms despite that 80% were taking medication to treat their IBS-C. Overall healthcare resource use and direct costs were asymmetric, with a small group of patients consuming the majority of resources.status: publishe