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1.
This paper provides a culturally-informed understanding of the impacts of climate change on a highly important subsistence activity that has been practiced by First Nations of central British Columbia for thousands of years. The paper begins with a review of the science regarding sockeye salmon and climate change. It discusses harvest patterns, and how the timing of runs has changed. A survey was conducted by the first author regarding St’át’imc traditional fishing at a historic site on the Fraser River, in 2005. The results show that the impacts of climate change are apparent to those conducting traditional fishing practices, in terms of changed timing and abundance of salmon runs. These perceptions fit closely with the information available from scientists and management agencies. These changes are highly problematic for the St’át’imc, in that the preservation method (drying) is tied to seasonal weather patterns. The whole cultural setting, and the relevance of salmon for subsistence would be highly altered by climate change that leads to changes in the timing and abundance of sockeye salmon. The paper discusses mitigation and adaptation alternatives, but also indicates the scope of these seem limited, given the resource systems and the context of these activities.  相似文献   

2.
Through shifts toward interactive and participatory forms of environmental governance, knowledge dynamics may come into play that differ from those of traditional forms of policy-making. This paper investigates how shifts of environmental governance and knowledge are related. In order to do so, it reconstructs the development of the governance of recreational boating in the Dutch Wadden Sea on the empirical basis of interviews, document analysis, and a focus group. Moreover, it analyzes this development by means of an analytical framework that combines governance modes, knowledge systems and knowledge–governance interfaces. Our results show that in the last decades partly an accumulation and partly a sequence of various governance arrangements concerning recreational boating has occurred; this has entailed a shift from predominantly centralized governance to a combination of governance modes with a stronger emphasis on decentralized, interactive and self-governance. This shift has occurred together with an increasing prominence of qualitative local knowledge, stakeholders’ knowledge, and the integration of various forms of knowledge. Furthermore, a shift has taken place toward more participatory knowledge–governance interfaces. Our analysis suggests that environmental governance and knowledge are interconnected in various ways: the regulatory and epistemic aspects of environmental issues are bound up with each other, and governance and knowledge are coproduced and mutually constitutive. Key lessons from this analysis are that room for experimentation is an important factor in improving environmental governance, and that increasing stakeholder involvement in governance implies that new modes of jointly creating and exchanging knowledge may need to be taken into account.  相似文献   

3.
Space programmes are shifting towards planetary exploration and, in particular, towards missions by human beings to the Moon and to Mars. Radiation is considered to be one of the major hazards for personnel in space and has emerged as the most critical issue to be resolved for long-term missions both orbital and interplanetary. The two cosmic sources of radiation that could impact a mission outside the Earth’s magnetic field are solar particle events (SPE) and galactic cosmic rays (GCR). Exposure to the types of ionizing radiation encountered during space travel may cause a number of health-related problems, but the primary concern is related to the increased risk of cancer induction in astronauts. Predictions of cancer risk and acceptable radiation exposure in space are extrapolated from minimal data and are subject to many uncertainties. The paper describes present-day estimates of equivalent doses from GCR and solar cosmic radiation behind various shields and radiation risks for astronauts on a mission to Mars.  相似文献   

4.
The Mariánské Lázn complex (MLC) is located in the Bohemian Massif along the north-western margin of the Teplá-Barrandian microplate and consists of metagabbro, amphibolite and eclogite, with subordinate amounts of serpentinite, felsic gneiss and calcsilicate rocks. The MLC is interpreted as a metaophiolite complex that marks the suture zone between the Saxothuringian rocks to the north-west and the Teplá-Barrandian microplate to the south-east. Sm-Nd geochronology of garnet-omphacite pairs from two eclogite samples yields ages of 377±7, and 367±4 Ma. Samples of eclogite and amphibolite do not define a whole rock Sm-Nd isochron, even though there is a large range in Sm/Nd ratio, implying that the suite of samples may not be cogenetic. Eclogites do not have correlated Nd values and initial 87Sr/86Sr ratios. Five of the eight eclogite samples have high Nd values (+10.2 to +7.1) consistent with derivation from a MORB-like source, but variable 87Sr/86Sr ratios (0.7033 to 0.7059) which probably reflect hydrothermal seawater alteration. Three other eclogite samples have lower Nd values (+ 5.4 to –0.8) and widely variable 87Sr/86Sr ratios (0.7033 to 0.7096). Such low Nd values are inconsistent with derivation from a MORB, source and may reflect a subduction or oceanic island basalt component in their source. The MLC is an important petrotectonic element in the Bohemian Massif, providing evidence for Cambro-Ordovician formation of oceanic crust and interaction with seawater, Late Devonian (Frasnian-Famennian) high- and medium-pressure metamorphism related to closure of a Saxothuringian ocean basin, Early Carboniferous (Viséan) thrusting of the Teplá terrane over Saxothuringian rocks and Late Viséan extension.  相似文献   

5.
All known cosmic and geological conditions and laws of chemistry and thermodynamics allow that complex organic matter could have formed spontaneously on pristine planet Earth about 4,000 mya. Simple gasses and minerals on the surface and in oceans of the early Earth reacted and were eventually organized in supramolecular aggregates and enveloped cells that evolved into primitive forms of life. Chemical evolution, which preceded all species of extant organisms, is a fact. In this review, we have concentrated on experimental and theoretical research published over the last two decades, which has added a wealth of new details and helped to close gaps in our previous understanding of this multifaceted field. Recent exciting progress in the molecular and genetic analyses of existing life, in particular microorganisms of ancient origin, even supports the possibility that a cellular, self-reproducing common ancestor might be assembled and resurrected in anaerobic cultures at some time in the future. Charles Darwin did not, and indeed, could not, address and specify the earliest phases of life which preceded the Origin of Species. However, in a famous letter, he sketched “a warm little pond with all sorts of… (chemicals, in which) …a protein was chemically formed.” We try to trace the impact of his charming clear-sighted metaphor up to the present time.  相似文献   

6.
The air quality in China has improved significantly in the last decade and,correspondingly,the characteristics of PM2.5have also changed.We studied the interannual variation of PM2.5in Chengdu,one of the most heavily polluted megacities in southwest China,during the most polluted season (winter).Our results show that the mass concentrations of PM2.5decreased significantly year-by-year,from 195.8±91.0μg/m3in winter 2016 to 96.1±39.3μg/m3in wi...  相似文献   

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