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Climate change and alpine stream biology: progress,challenges, and opportunities for the future 下载免费PDF全文
Scott Hotaling J. Joseph Giersch David W. Weisrock Dean Jacobsen 《Biological reviews of the Cambridge Philosophical Society》2017,92(4):2024-2045
In alpine regions worldwide, climate change is dramatically altering ecosystems and affecting biodiversity in many ways. For streams, receding alpine glaciers and snowfields, paired with altered precipitation regimes, are driving shifts in hydrology, species distributions, basal resources, and threatening the very existence of some habitats and biota. Alpine streams harbour substantial species and genetic diversity due to significant habitat insularity and environmental heterogeneity. Climate change is expected to affect alpine stream biodiversity across many levels of biological resolution from micro‐ to macroscopic organisms and genes to communities. Herein, we describe the current state of alpine stream biology from an organism‐focused perspective. We begin by reviewing seven standard and emerging approaches that combine to form the current state of the discipline. We follow with a call for increased synthesis across existing approaches to improve understanding of how these imperiled ecosystems are responding to rapid environmental change. We then take a forward‐looking viewpoint on how alpine stream biologists can make better use of existing data sets through temporal comparisons, integrate remote sensing and geographic information system (GIS) technologies, and apply genomic tools to refine knowledge of underlying evolutionary processes. We conclude with comments about the future of biodiversity conservation in alpine streams to confront the daunting challenge of mitigating the effects of rapid environmental change in these sentinel ecosystems. 相似文献
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Sound is an inherent component of the environment that provides conditions and information necessary for many animal activities. Soniferous species require specific acoustic and physical conditions suitable for their signals to be transmitted, received, and effectively interpreted to successfully identify and utilize resources in their environment and interact with conspecifics and other heterospecific organisms. We propose the Acoustic Habitat Hypothesis to explain how the acoustic environment influences habitat selection of sound-dependent species. We postulate that sound-dependent species select and occupy habitats with unique acoustic characteristics that are essential to their functional needs and conducive to the threshold of sound frequency they produce and detect. These acoustic habitats are based on the composition of biophony, geophony, and technophony in the soundscape and on the biosemiotics mechanisms described in the eco-field hypothesis. The Acoustic Habitat Hypothesis initiates questions of habitat selection that go beyond the physical attributes of the environment by applying ecoacoustics theory. We outline the theoretical basis of the Acoustic Habitat Hypothesis and provide examples from the literature to support its assumptions. The concept of acoustic habitats has been documented in the literature for many years but here, we accurately and extensively define acoustic habitat and we put this concept into a unified theory. We also include perspectives on how the Acoustic Habitat Hypothesis can stimulate a paradigm shift in conservation strategies for threatened and endangered species. 相似文献
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While supertrees have been built for many vertebrate groups (notably birds, mammals and dinosaurs), invertebrates have attracted relatively little attention. The paucity of supertrees of arthropods is particularly surprising given their economic and ecological importance, as well as their overwhelming contribution to biodiversity. The absence of comprehensive archives of machine-readable source trees, coupled with the need for software implementing repeatable protocols for managing them, has undoubtedly impeded progress. Here we present a supertree of Achelata (spiny, slipper and coral lobsters) as a proof of concept, constructed using new supertree specific software (the Supertree Toolkit; STK) and following a published protocol. We also introduce a new resource for archiving and managing published source trees. Our supertree of Achelata is synthesised from morphological and molecular source trees, and represents the most complete species-level tree of the group to date. Our findings are consistent with recent taxonomic treatments, confirming the validity of just two families: Palinuridae and Scyllaridae; Synaxidae were resolved within Palinuridae. Monophyletic Silentes and Stridentes lineages are recovered within Palinuridae, and all sub-families within Scyllaridae are found to be monophyletic with the exception of Ibacinae. We demonstrate the feasibility of building larger supertrees of arthropods, with the ultimate objective of building a complete species-level phylogeny for the entire phylum using a divide and conquer strategy. 相似文献
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Tom P. Moorhouse Cecilia A. L. Dahlsj? Sandra E. Baker Neil C. D'Cruze David W. Macdonald 《PloS one》2015,10(10)
Tourism accounts for 9% of global GDP and comprises 1.1 billion tourist arrivals per annum. Visits to wildlife tourist attractions (WTAs) may account for 20–40% of global tourism, but no studies have audited the diversity of WTAs and their impacts on the conservation status and welfare of subject animals. We scored these impacts for 24 types of WTA, visited by 3.6–6 million tourists per year, and compared our scores to tourists’ feedback on TripAdvisor. Six WTA types (impacting 1,500–13,000 individual animals) had net positive conservation/welfare impacts, but 14 (120,000–340,000 individuals) had negative conservation impacts and 18 (230,000–550,000 individuals) had negative welfare impacts. Despite these figures only 7.8% of all tourist feedback on these WTAs was negative due to conservation/welfare concerns. We demonstrate that WTAs have substantial negative effects that are unrecognised by the majority of tourists, suggesting an urgent need for tourist education and regulation of WTAs worldwide. 相似文献
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Marisa H. Miceli Tracey Churay Thomas Braun Carol A. Kauffman Daniel R. Couriel 《Mycopathologia》2017,182(5-6):495-504
Allogeneic hematopoietic cell transplant (HCT) recipients are at increased risk of invasive fungal infections (IFI), which are associated with a high mortality rate. We evaluated the impact of IFI in allogeneic HCT patients. In total, 541 consecutive allogeneic HCT recipients were included. The cumulative incidence of any IFI and mold infections at 1-year post-HCT was 10 and 7%, respectively. Median times to IFI and mold infection were 200 and 210 days, respectively. There was a trend toward fewer IFI and mold infections in the last several years. Both acute graft-versus-host disease (GVHD) (OR 1.83, p = 0.05) and corticosteroid duration (OR 1.0, p = 0.026) were significantly associated with increased risk of IFI, acute GVHD (OR 2.3, p = 0.027) emerged as the most important association with mold infections. Any IFI [HR 4.1 (2.79–6.07), p < 0.0001] and mold infections [HR 3.34 (2.1–5.1), p < 0.0001] were independently associated with non-relapse mortality (NRM). This association persisted in the setting of both acute and chronic GVHD. Corticosteroid treatment for >90 days was also significantly associated with higher NRM [HR 1.9 (1.3–2.6), p < 0.0001]. This study highlights the impact of IFI on NRM among HCT patients. The decrease in number of IFI and mold infections over the last several years may reflect the benefit of prophylaxis with mold-active antifungal agents. 相似文献
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Leaf phenology mediates provenance differences in herbivore populations on valley oaks in a common garden 下载免费PDF全文
IAN S. PEARSE JILL H. BATY DUSTIN HERRMANN RICHARD SAGE WALTER D. KOENIG 《Ecological Entomology》2015,40(5):525-531
1. Plants from different populations often display a variation in herbivore resistance. However, it is rarely understood what plant traits mediate such differences. 2. It was tested how leaf phenology affects herbivore populations in a 15‐year‐old common garden of valley oaks (Quercus lobata Née) with different populations and maternal parents from throughout the Q. lobata range. 3. The abundance of leaf miners (Stigmella sp. Shrank) and leaf phenology of oaks in the common garden was measured. 4. Leaf miner abundance varied among provenance locations (population), but not among maternal parents within populations. Leaf phenology varied by provenance location and maternal parent, and trees that leafed out earlier accrued higher leaf‐miner abundance. Path analysis indicated that leaf phenology was the likely driver of provenance and parental differences in resistance to leaf miners. 5. Understanding population differences is particularly important when considering transport of genotypes for ornamental or restoration purposes. The present study suggests that similarity in leaf phenology may be one factor that could be used to find genotypes with a similar herbivore resistance to local genotypes. 相似文献