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1.
Abstract

The concept of a bioeconomy has been placed central in formation of a Swedish National Forest Program (NFP). Drawing on Hajer’s conceptual framework of storylines, we present a discourse analysis of the working group reports underlying the establishment of the NFP strategy. We ask what stories about Swedish forests come to dominate the NFP process, how well they reflect the commitment of balancing economic, social and environmental interests, and what role the concept of a bioeconomy, has on the formation of these stories. Storylines of Swedish forests in the bioeconomy unite wider European discourses on the bioeconomy and climate change with historical Swedish forest policy discourses, revitalizing a discourse coalition comprising the state and the industry. Particular to the Swedish discourse is the strong emphasis on creating consensus around a single story of the forest-based bioeconomy.  相似文献   
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Broadly speaking, there is, at least within geomorphic circles, a general acceptance that rocks with low albedos will warm both faster and to higher temperatures than rocks with high albedos, reflectivity influencing radiative warming. Upon this foundation are built notions of weathering in respect of the resulting thermal differences, both at the grain scale and at the scale of rock masses. Here, a series of paving bricks painted in 20 per cent reflectivity intervals from black through to white were used to monitor albedo‐influenced temperatures at a site in northern Canada in an attempt to test this premise. Temperatures were collected, for five months, for the rock surface and the base of the rock, the blocks being set within a mass of local sediment. Resulting thermal data did indeed show that the dark bricks were warmer than the white but only when their temperatures were equal to or cooler than the air temperature. As brick temperature exceeded that of the air, so the dark and light bricks moved to parity; indeed, the white bricks frequently became warmer than the dark. It is argued that this ‘negating’ of the albedo influence on heating is a result of the necessity of the bricks, both white and black, to convect heat away to the surrounding cooler air; the darker brick, being hotter, initially convects faster than the white as a product of the temperature difference between the two media. Thus, where the bricks become significantly hotter than the air, they lose energy to that air and so their respective temperatures become closer, the albedo influence being superceded by the requirement to equilibrate with the surrounding air. It is argued that this finding will have importance to our understanding of weathering in general and to our perceptions of weathering differences between different lithologies. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
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Report     
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Climates of equatorial East Africa and subtropical Southern Africa have varied inversely over long periods of time. The high-resolution 18O stalagmite record from Cold Air Cave in the Makapansgat valley in South Africa and a similar resolution lake-level record for Lake Naivasha in Kenya have been in anti-phase for much of the last thousand years. A similar relationship is evident in the twentieth century meteorological record. The changes in rainfall in the two regions on multi-decadal to centennial scales have influenced both settlement patterns and livelihoods of Iron Age agriculturalists. The resulting latitudinal gradient of change may have been a significant factor in promoting southward migration of Sotho-Tswana speaking people from equatorial East Africa during the first few centuries of the last millennium and earlier. This would have occurred at times when environments in the north were deteriorating and those to the south were ameliorating.  相似文献   
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We aim to show how some of the important interdisciplinary fixes or solutions to diverse problems observed in fisheries can complement each other. This can be achieved through methodical allocation of the rights pertaining to fisheries and simultaneous implementation of policy instruments to correct for market failures and equity concerns. We emphasize via a roadmap that there are some general principles that should be invoked when choosing between alternative structures of rights. Our examples from Sweden provide evidence of the flexibility of fishing rights and how they can be adapted to integrate fixes from different disciplines into practical fisheries management.  相似文献   
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Results from an ionoipheric founding rocket of the “mother-daugther” type, equipped with an 8 keV electron accelerator, is reported. The emphasis is on the results obtained from the three plasma probes which monitored both the electron- and the ion-population. It is shown that no significant increase of the electron density was observed during the beam injections. However, the electron temperature varied rapidly during these pulses. The influence of the vehicle charging on the measurements is also discussed.  相似文献   
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The stable isotope compositions of organic carbon and nitrogen, the contents of organic carbon and nitrogen and C/N ratios for two cores recovered from the Empakai Crater at water depths of 11 and 20 m are used to document climatic changes in northern Tanzania. Eight 14C AMS dates determined on total organic matter (OM) indicate that the sedimentation rate in this lake is about 30 cm/ka for the late Pleistocene to early Holocene period. There are differences in the δ13C values of organic carbon between the two cores, which may be a result of differences in location from the present shoreline and of different water depths. In the deeper-water core the δ13C values show a general downcore decrease to the base of the core with a sharp change to lower values of about 4‰ at a depth of 100 cm (8.7 ka). The general trend of downcore decrease in 13C values can be attributed either to a systematic decrease in the relative proportion of C4 type of OM, owing to an increase in precipitation and change in vegetation cover from grassland to forest, or to utilization of isotopically enriched carbon during photosynthesis. The δ15N values show a general downcore increase with again a sharp change of about 5‰ to lower values at about 8.7 ka. A sharp change of about 5‰ and 4‰ to more depleted values at a depth of 100 cm of both 15N and 13C, respectively, suggests either hiatus or abrupt change in climatic condition from wetter conditions to drier conditions. There is enhanced preservation of OM in the lake as depicted by high mean values of organic carbon and nitrogen at both sites.  相似文献   
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