67 research outputs found

    Systematic Conservation Planning in the Face of Climate Change: Bet-Hedging on the Columbia Plateau

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    Systematic conservation planning efforts typically focus on protecting current patterns of biodiversity. Climate change is poised to shift species distributions, reshuffle communities, and alter ecosystem functioning. In such a dynamic environment, lands selected to protect today's biodiversity may fail to do so in the future. One proposed approach to designing reserve networks that are robust to climate change involves protecting the diversity of abiotic conditions that in part determine species distributions and ecological processes. A set of abiotically diverse areas will likely support a diversity of ecological systems both today and into the future, although those two sets of systems might be dramatically different. Here, we demonstrate a conservation planning approach based on representing unique combinations of abiotic factors. We prioritize sites that represent the diversity of soils, topographies, and current climates of the Columbia Plateau. We then compare these sites to sites prioritized to protect current biodiversity. This comparison highlights places that are important for protecting both today's biodiversity and the diversity of abiotic factors that will likely determine biodiversity patterns in the future. It also highlights places where a reserve network designed solely to protect today's biodiversity would fail to capture the diversity of abiotic conditions and where such a network could be augmented to be more robust to climate-change impacts

    A Tale of Four “Carp”: Invasion Potential and Ecological Niche Modeling

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    . We assessed the geographic potential of four Eurasian cyprinid fishes (common carp, tench, grass carp, black carp) as invaders in North America via ecological niche modeling (ENM). These “carp” represent four stages of invasion of the continent (a long-established invader with a wide distribution, a long-established invader with a limited distribution, a spreading invader whose distribution is expanding, and a newly introduced potential invader that is not yet established), and as such illustrate the progressive reduction of distributional disequilibrium over the history of species' invasions.We used ENM to estimate the potential distributional area for each species in North America using models based on native range distribution data. Environmental data layers for native and introduced ranges were imported from state, national, and international climate and environmental databases. Models were evaluated using independent validation data on native and invaded areas. We calculated omission error for the independent validation data for each species: all native range tests were highly successful (all omission values <7%); invaded-range predictions were predictive for common and grass carp (omission values 8.8 and 19.8%, respectively). Model omission was high for introduced tench populations (54.7%), but the model correctly identified some areas where the species has been successful; distributional predictions for black carp show that large portions of eastern North America are at risk.ENMs predicted potential ranges of carp species accurately even in regions where the species have not been present until recently. ENM can forecast species' potential geographic ranges with reasonable precision and within the short screening time required by proposed U.S. invasive species legislation

    Coagulation changes in elective surgery and trauma.

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    Although antithrombin-3 (AT-3), a naturally-occurring inhibitor of thrombin, has been associated with a variety of thrombotic disorders, it has been studied in surgery and trauma. Three groups of patients were studied: Group I (20 patients) who underwent elective surgery; Group II (ten patients) who sustained moderate trauma: Group III (ten patients) who sustained severe trauma. Hypercoagulability panels were run preoperatively, intraoperatively, and postoperatively. Nine units of banked blood were also tested. The coagulation pattern changed during the stress, becoming hypercoagulable in proportion to the stress endured by the patient. In the severe trauma group, AT-3 fell significantly (p less than or equal to 0.002) in all patients, indicating extreme hypercoagulability. Three of these patients sustained thrombosis and loss of the involved extremity. The banked blood was found to be hypercoagulable. It appears that patients who sustain severe trauma, have multiple transfusions, and major operative procedures are at increased risk of developing postoperative thrombotic complications, including loss of limb
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