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131.
Industrial accidents triggered by earthquakes,floods and lightning: lessons learned from a database analysis 总被引:2,自引:0,他引:2
Elisabeth Krausmann Elisabetta Renni Michela Campedel Valerio Cozzani 《Natural Hazards》2011,59(1):285-300
Natural hazards and disasters can cause major accidents in chemical and process installations. These so-called Natech accidents
can result in hazardous-materials releases due to damage to process and storage units, or pipes. In order to understand the
dynamics of Natech events, accidents triggered by earthquakes, floods and lightning recorded in industrial accident databases
were analysed. This allowed the identification of the most vulnerable equipment types, their modes of failure due to natural-event
impact and the final accident scenarios. Moreover, lessons learned for future accident prevention and mitigation were derived.
The analysis showed that pipes and storage tanks are the most vulnerable equipment for earthquakes, floods and lightning,
calling for more research of equipment behaviour under natural-event loading. The damage modes and states are strongly dependent
on the characteristics of the impacting natural event. Toxic dispersion, fires and explosions were observed as a consequence
of all three types of analysed natural events. In the case of floods, two additional scenarios were identified. These are
water contamination and the formation of toxic and/or flammable vapours upon reaction of the released chemicals with the floodwaters.
The overall number of recorded Natech accidents was found to range from 2 to 5% of all reported accidents in the analysed
databases. 相似文献
132.
Andreas Matzarakis Stefan Muthers Elisabeth Koch 《Theoretical and Applied Climatology》2011,105(1-2):1-10
The relationship between heat stress and mortality in the federal state of Vienna (Austria) was analyzed from 1970 to 2007. Long-term trends of mortality data and short-term adaptation to heat stress were considered by two complex approaches. The evaluation is based on the human biometeorological parameter, physiologically equivalent temperature. The results revealed a significant impact of heat stress on the human health, with a significantly higher sensitivity on women compared to men. Additionally, higher risks of deaths due to cardiovascular and respiratory diseases were found. During the long period of 38?years, some significant decreases of the sensitivity were found, especially in the medium heat stress levels. This could indicate active processes of long-term adaptation to the increasing heat stress. 相似文献
133.
Elisabeth RAMM Chunyan LIU Xianwei WANG Hongyu YUE Wei ZHANG Yuepeng PAN Michael SCHLOTER Silvia GSCHWENDTNER Carsten W. MUELLER Bin HU Heinz RENNENBERG Michael DANNENMANN 《大气科学进展》2020,37(8):793-799
正1.Introduction:permafrost carbon and nitrogen feedback to climate change Permafrost refers to any ground, including soils, sediments and rocks, with a temperature at or below the freezing point of water (0℃) for two or more consecutive years (Biskaborn et al., 2019). Permafrost soils of the Northern Hemisphere store vast amounts of both organic carbon (C) and nitrogen (N)(Tarnocai et al., 2009; Harden et al., 2012; Mueller et al., 相似文献
134.
Lila Nath Sharma Ole Reidar Vetaas Ram Prasad Chaudhary Inger Elisabeth Måren 《山地科学学报》2014,11(4):838-849
The ecotone, the spatial transition zone between two vegetation communities, is claimed to have more species than the adjoining communities. However, empirical studies do not always confirm higher richness at the ecotone. The ecotone position and structure are dynamic over time and space and it is driven by the changes in climate, land use or their interaction. In this context, we assessed the forest- grassland ecotone of temperate mountains in central Nepal by i) comparing species composition and richness across the ecotone, ii) analyzing if the forestgrassland ecotone is shifting towards the grassland center by colonizing them with trees, and iii) discussing the consequence of changed disturbance regime in the dynamics of this ecotone and the surrounding grasslands. We analyzed vegetation data sampled from belt transects laid across the forest- grassland ecotone in semi-natural grassland patches. Vegetation data consisting of species richness and composition, and size structure and regeneration of the two most dominant tree species, namely Rhododendron arboreum and Abies spectabilis, from the transects, were used to analyze the trend of the forest-grassland ecotone. Forest and grasslands were different in terms of floristic composition and diversity. Vascular plant speciesrichness linearly increased while moving from forest interior to grassland center. Spatial pattern of tree size structure and regeneration infers that forest boundary is advancing towards the grasslands at the expense of the grassland area, and tree establishment in the grasslands is part of a suceessional process. Temporally, tree establishment in grasslands started following the gradual decline in disturbance. We argue that local processes in terms of changed land use may best explain the phenomenon of ecotone shift and consequent forest expansion in these grasslands. We underpin the need for further research on the mechanism, rate and spatial extent of ecotone shift by using advaneed tools to understand the process indepth. 相似文献
135.
Alexie Heimburger Mickael Tharaud Fabrice Monna Rémi Losno Karine Desboeufs Elisabeth B. Nguyen 《Geostandards and Geoanalytical Research》2013,37(1):77-85
The fifth version of natural river water certified reference material, SLRS‐5 (National Research Council – Conseil National de Recherches Canada), is commonly used to control the quality of major and trace element measurements. Concentrations of silicon and thirty‐one uncertified trace elements have been reported for the certified reference material SLRS‐4, but they are not yet available for SLRS‐5. Here, SLRS‐5/SLRS‐4 ratios were deduced from SLRS‐5 and SLRS‐4 measurements by inductively coupled plasma‐atomic emission spectrometry and high‐resolution inductively coupled plasma‐mass spectrometry for certified elements and thirty‐five uncertified elements (rare earth elements, B, Bi, Br, Cs, Ga, Ge, Hf, Li, Nb, P, Pd, Rb, Rh, S, Sc, Si, Sn, Th, Ti, Tl, Y). Both reference materials were measured directly one after the other, so that calculated elemental ratios would not be notably influenced either by calibration uncertainties or by eventual long‐term instrumental drift. The computed ratios are in good agreement with those deduced from the certified values. We also report concentrations for thirty‐three uncertified elements in SLRS‐5 by combining the measured SLRS‐5/SLRS‐4 ratios and the published SLRS‐4 values. The resulting new data set provides target SLRS‐5 values, which will be useful in quality control procedures. 相似文献
136.
Robert Marchant Hermann Behling Juan‐Carlos Berrio Antoine Cleef Joost Duivenvoorden Henry Hooghiemstra Peter Kuhry Bert Melief Elisabeth Schreve‐Brinkman Bas Van Geel Thomas Van der Hammen Guido Van Reenen Michael Wille 《第四纪科学杂志》2002,17(2):113-129
Colombian biomes are reconstructed at 45 sites from the modern period extending to the Last Glacial Maximum (LGM). The basis for our reconstruction is pollen data assigned to plant functional types and biomes at six 3000‐yr intervals. A reconstruction of modern biomes is used to check the treatment of the modern pollen data set against a map of potential vegetation. This allows the biomes reconstructed at past periods to be assessed relative to the modern situation. This process also provides a check on the a priori assignment of pollen taxa to plant functional types and biomes. For the majority of the sites, the pollen data accurately reflect the potential vegetation, even though much of the original vegetation has been transformed by agricultural practices. At 18 000 14C yr BP, a generally cool and dry environment is reflected in biome, assignments of cold mixed forests, cool evergreen forests and cool grassland–shrub; the latter extending to lower altitudes than presently recorded. This signal is strongly recorded at 15 000 and 12 000 14C yr BP, the vegetation at these times also reflecting a relatively cool and dry environment. At 9000 14C yr BP there is a shift to biomes thought to result from slightly cooler environmental conditions. This trend is reversed by 6000 14C yr BP; most sites, within a range of different environmental settings, recording a shift to more xeric biome types. There is an expansion of steppe and cool mixed‐forest biomes, replacing tropical dry forest and cool grassland–shrub biomes, respectively. These changes in biome assignments from the modern situation can be interpreted as a biotic response to mid‐Holocene climatic aridity. At 3000 14C yr BP the shift is mainly to biomes characteristic of slightly more mesic environmental conditions. There are a number of sites that do not change biome assignment relative to the modern reconstruction, although the affinities that these sites have to a specific biome do change. These ‘anomalies’ are interpreted on a site‐by‐site basis. Spatially constant, but differential response of the vegetation to climatic shifts are related to changes in moisture sources and the importance of edaphic controls on the vegetation. The Late Quaternary reconstruction of large‐scale vegetation dynamics in Colombia allows an understanding of the environmental controls on these to be developed. In particular, shifts in the character of the main climatic systems that influence Colombian vegetation are described. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
137.
Human land use contributes significantly to the growth of greenhouse gases in the atmosphere. Changes in land management practices have been proposed as a critical and cost-effective mechanism for reducing greenhouse gas emissions and promoting the storage of additional carbon in vegetation and soils. However many discussions of the potential for land use to mitigate climate change only take into account biophysical factors such as vegetation and land cover and neglect how the agency of land owners themselves affects whether additional carbon storage can be achieved. Unlike many potential REDD opportunities in developing countries, land management in the U.S. to enhance carbon sequestration would occur against a backdrop of clearly defined, legally enforceable land ownership. In addition, more than a third of the land surface in the U.S. is managed by federal agencies who operate under legal guidelines for multiple use and is subject to demands from multiple constituencies. We set out to investigate how the goal of enhancing carbon sequestration through land use is perceived or implemented in one region of the U.S., and how this goal might intersect the existing drivers and incentives for public and private land use decision making. We conducted a case study through interviews of the major categories of landowners in the state of Colorado, which represents a mixture of public and privately held lands. By analyzing trends in interview responses across categories, we found that managing for carbon is currently a fairly low priority and we identify several barriers to more widespread consideration of carbon as a management priority including competing objectives, limited resources, lack of information, negative perceptions of offsetting and lack of a sufficient policy signal. We suggest four avenues for enhancing the potential for carbon to be managed through land use including clarifying mandates for public lands, providing compelling incentives for private landowners, improving understanding of the co-benefits and tradeoffs of managing for carbon, and creating more usable science to support decision making. 相似文献
138.
139.
140.
Elisabeth Bondar-Kunze Stefan Preiner Friedrich Schiemer Gabriele Weigelhofer Thomas Hein 《Aquatic Sciences - Research Across Boundaries》2009,71(4):437-447
This study evaluated the effects of a controlled surface water connectivity scheme on several backwaters in an urban floodplain
within the city limits of Vienna, the Upper Lobau. A phosphorus budget and ecosystem metabolism measurements were used to
assess the reaction of two trophically distinct floodplain backwater sections on changed connectivity conditions. The surface
water connection led to a reduction of the retention times in the backwater system. The water column nutrient concentrations
in the individual backwater sections approached those of the source water body. The significance of these effects, however,
depends on the historical and current trophic situation of the respective water bodies. Generally, the surface water connectivity
introduced particulate phosphorus export up to 30% increase over the influent loading and dissolved phosphorus up to 14% increase
over the influent loading. However, in sections with submersed macrophyte development, which provided enhanced filtering capacities
for particulate matter, sediment and phosphorus accumulation rates were increased. At the same time, water transparency increased
resulting in a positive feedback supporting further macrophyte development. Based on these findings, the evaluation of restoration
measures in urban floodplains needs to consider the spatial and temporal dynamics of nutrients and ecosystem processes such
as gross primary production and community respiration to predict long-term development. 相似文献