The deep sea (>200 m depth) encompasses >95% of the world's ocean volume and represents the largest and least explored biome on Earth (<0.0001% of ocean surface), yet is increasingly under threat from multiple direct and indirect anthropogenic pressures. Our ability to preserve both benthic and pelagic deep-sea ecosystems depends upon effective ecosystem-based management strategies and monitoring based on widely agreed deep-sea ecological variables.
View Article and Find Full Text PDFCommercial-scale mining for polymetallic nodules could have a major impact on the deep-sea environment, but the effects of these mining activities on deep-sea ecosystems are very poorly known. The first commercial test mining for polymetallic nodules was carried out in 1970. Since then a number of small-scale commercial test mining or scientific disturbance studies have been carried out.
View Article and Find Full Text PDFThe number of records of the genus Prionospio Malmgren, 1867, from the deep sea (>2000 m) are relatively few and do not reflect the actual occurrence of species nor their potential ecological importance. In this paper we describe five new species of this genus (Prionospio amarsupiata sp. nov.
View Article and Find Full Text PDFIt has been challenging to establish the mechanisms that link ecosystem functioning to environmental and resource variation, as well as community structure, composition, and compensatory dynamics. A compelling hypothesis of compensatory dynamics, known as "zero-sum" dynamics, is framed in terms of energy resource and demand units, where there is an inverse link between the number of individuals in a community and the mean individual metabolic rate. However, body size energy distributions that are nonuniform suggest a niche advantage at a particular size class, which suggests a limit to which metabolism can explain community structuring.
View Article and Find Full Text PDFOngoing greenhouse gas emissions can modify climate processes and induce shifts in ocean temperature, pH, oxygen concentration, and productivity, which in turn could alter biological and social systems. Here, we provide a synoptic global assessment of the simultaneous changes in future ocean biogeochemical variables over marine biota and their broader implications for people. We analyzed modern Earth System Models forced by greenhouse gas concentration pathways until 2100 and showed that the entire world's ocean surface will be simultaneously impacted by varying intensities of ocean warming, acidification, oxygen depletion, or shortfalls in productivity.
View Article and Find Full Text PDFIn contrast to generally sparse biological communities in open-ocean settings, seamounts and ridges are perceived as areas of elevated productivity and biodiversity capable of supporting commercial fisheries. We investigated the origin of this apparent biological enhancement over a segment of the North Mid-Atlantic Ridge (MAR) using sonar, corers, trawls, traps, and a remotely operated vehicle to survey habitat, biomass, and biodiversity. Satellite remote sensing provided information on flow patterns, thermal fronts, and primary production, while sediment traps measured export flux during 2007-2010.
View Article and Find Full Text PDFSpatial patchiness in marine surface bacterioplankton populations was investigated in the Southern Ocean, where the Antarctic Circumpolar Current meets the islands of the Scotia Arc and is subjected to terrestrial input, upwelling of nutrients and seasonal phytoplankton blooms. Total bacterioplankton population density, group-specific taxonomic distribution and six of eight dominant members of the bacterioplankton community were found to be consistent across 18 nearshore sites at eight locations around the Scotia Arc. Results from seven independent 16S rRNA gene clone libraries (1223 sequences in total) and fluorescent in situ hybridization suggested that microbial assemblages were predominantly homogeneous between Scotia Arc sites, where the Alphaproteobacteria, Gammaproteobacteria and the Cytophaga-Flavobacterium-Bacteroidetes cluster were the dominant bacterial groups.
View Article and Find Full Text PDFEchinoderms are important components of deep-sea communities because of their abundance and the fact that their activities contribute to carbon cycling. Estimating the echinoderm contribution to food webs and carbon cycling is important to our understanding of the functioning of the deep-sea environment and how this may alter in the future as climatic changes take place. Metabolic rate data from deep-sea echinoderm species are, however, scarce.
View Article and Find Full Text PDFThe addition of iron to high-nutrient low-chlorophyll (HNLC) oceanic waters stimulates phytoplankton, leading to greater primary production. Large-scale artificial ocean iron fertilization (OIF) has been proposed as a means of mitigating anthropogenic atmospheric CO(2), but its impacts on ocean ecosystems below the photic zone are unknown. Natural OIF, through the addition of iron leached from volcanic islands, has been shown to enhance primary productivity and carbon export and so can be used to study the effects of OIF on life in the ocean.
View Article and Find Full Text PDFSocietal concerns over the potential impacts of recent global change have prompted renewed interest in the long-term ecological monitoring of large ecosystems. The deep sea is the largest ecosystem on the planet, the least accessible, and perhaps the least understood. Nevertheless, deep-sea data collected over the last few decades are now being synthesised with a view to both measuring global change and predicting the future impacts of further rises in atmospheric carbon dioxide concentrations.
View Article and Find Full Text PDFClimate variation affects surface ocean processes and the production of organic carbon, which ultimately comprises the primary food supply to the deep-sea ecosystems that occupy approximately 60% of the Earth's surface. Warming trends in atmospheric and upper ocean temperatures, attributed to anthropogenic influence, have occurred over the past four decades. Changes in upper ocean temperature influence stratification and can affect the availability of nutrients for phytoplankton production.
View Article and Find Full Text PDFA rural health services development program of the University of Washington School of Medicine has worked for 15 years with communities throughout the five-state region of Alaska, Idaho, Montana, Washington and Wyoming to strengthen their health systems. In the course of that work, 56 communities were surveyed about their utilization and opinions of local health systems. This database allows the following generalizations to be made about rural Northwest communities: (1) People think highly of their local hospitals, physicians and other key components of the acute medical care system and want their hospitals to remain open.
View Article and Find Full Text PDFA District Diabetes Register has been created using the Family Health Services Computer Unit system, DIALOG, linked to the Family Health Services Authority (FHSA) population register. Initial informal discussions between the Diabetes Centre, Public Health, and the FHSA led to a formal proposal being accepted by the Local Diabetes Services Advisory Group to pilot the DIALOG software. Following installation of DIALOG on a separate computer, electronically linked to the main FHSA system, the register was compiled.
View Article and Find Full Text PDFTwo patients with giant cell tumour of the lateral tibial condyle underwent en bloc resection and reconstruction by pedicled vascularized fibular graft. Both had good functional results and rapid solid bony union. This procedure preserved the lateral stabilizing structures of the knee, allowed relatively early mobilization and provided some cartilagionous surface for articulation with the lateral femoral condyle.
View Article and Find Full Text PDFSix unreduced posterior dislocations of the elbow are reported and the clinical details, operative procedures, and results obtained are presented. The literature is reviewed and the necessity of triceps V-Y plasty at operation discussed.
View Article and Find Full Text PDFTwo cases of fracture of the proximal third of the radius, one with anterolateral, and one with posterior dislocation of the radial head are described. In both the ulna remained intact. To the best of our knowledge, only one other similar case had been reported.
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