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41.
42.
Sue Walker 《Climatic change》2005,70(1-2):311-318
Agricultural meteorologists are concerned with many operational aspects of the effects of climate on crop production, livestock, and natural resource management. For them to continue to make a contribution to the economy of a country they must continually sharpen their skills and remain updated on the latest available information. Training should include a variety of skills, including transferable skills (e.g. communication, numeracy), professional skills (including cognitive skills) and information technology skills. Problem-based learning can be used to promote critical thinking, decision making and analytical skills. More use should be made of computer-aided learning for agricultural meteorologists’ in-service training. In particular, the Internet or CDs could be used to disseminate specific recently developed techniques and applications to improve the understanding of the variability in climate and its effect on agricultural production and natural resource management. Examples that can address the vulnerability of farmers include crop–climate matching, the use of indices, crop modelling and risk assessment together with seasonal outlooks. A strategy needs to be formulated to address these needs and implement changes in the education and training of agricultural meteorologists. These training needs must be constantly updated to meet the changing demands of new technology to cope with climate change and climate variability.  相似文献   
43.
The Peter Gruber Foundation, along with the International Congress of Distinguished Awards, has instituted the world's first award devoted to cosmology, with a cash prize of $150 000.
Click HERE to view the article.  相似文献   
44.
Evidence for relative sea‐level changes during the middle and late Holocene is examined from two locations on the Atlantic coast of Harris, Outer Hebrides, Scotland, using morphological mapping and survey, stratigraphical, grain size and diatom analysis, and radiocarbon dating. The earliest event identified is a marine flood, which occurred after 7982–8348 cal. a (7370 ± 80 14C a) BP, when the sea crossed a threshold lying at ?0.08 m Ordnance Datum Newlyn (OD) (?2.17 m mean high water springs (MHWS)) before withdrawing. This could have been due to a storm or to the Holocene Storegga Slide tsunami. By 6407–6122 cal. a (5500 ± 60 14C a) BP, relative sea levels had begun to fall from a sandflat surface with an indicated MHWS level of between 0.08 and ?1.96 m (?2.01 to ?4.05 m). This fall reached between ?0.30 and ?2.35 m (?2.39 to ?4.44 m) after 5841–5050 cal. a (4760 ± 130 14C a) BP, but was succeeded by a relative sea‐level rise which reached between 0.54 and ?1.57 m (?1.55 to ?3.66 m) by 5450–4861 cal. a (4500 ± 100 14C a) BP. This rise continued, possibly with an interruption, until a second sandflat surface was reached between 2.34 and ?0.26 m (0.25 to ?2.35 m) between 2952–3375 cal. a (3000 ± 80 14C a) and 1948–2325 cal. a (2130 ± 70 14C a) BP, before present levels were reached. The regressive episode from the earliest sandflat is correlated with the abandonment of the Main Postglacial Shoreline. It is maintained that the fluctuations in relative sea level recorded can be correlated with similar events elsewhere on the periphery of the glacio‐isostatic centre and may therefore reflect secular changes in nearshore sea surface levels. Despite published evidence from trim lines of differential ice sheet loading across the area, no evidence of variations in uplift between the locations concerned could be found. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
45.
The November 3, 2002 Denali-Alaska earthquake (Mw=7.9) caused significant liquefaction associated damage to various infrastructure built on fine-grained soils. The seismic response, liquefaction potential, and excess pore pressure generation of soils in cold regions, especially those of fine-grained nature, have not been studied thoroughly and therefore are not well-understood. This paper presents results from an extensive laboratory study on the characteristics of excess pore pressure generation and liquefaction potential of fine-grained soils. Laboratory-constituted soils specimens were tested in four categories: (1) tests on specimens subjected to no thermal conditioning or freeze–thaw cycles; (2) tests on specimens conditioned at 24, 5, 1, 0.5, and −0.2 °C; (3) tests on specimens subjected to 1–4 freeze–thaw cycles; and (4) tests on specimens conditioned at near-freezing temperatures of 0.5 and −0.2 °C through different freeze–thaw paths. Strain-controlled, undrained, cyclic triaxial tests were performed at shear strain levels of 0.005–0.8%. Specimens conditioned at different temperatures were found to generate significantly different pore pressures with cyclic loading. The excess pore pressure generation at near or slightly below freezing was found to change dramatically. A transitional change in the dynamic soil behavior, attributed to unfrozen- or frozen-dominant pore water, was discovered. The threshold shear strain was also found to be influenced by the temperature. Subjecting the soil specimens to 1, 2 and 4 freeze–thaw cycles caused a reduction in excess pore pressure generation and slight change in the threshold shear strain. The temperature conditioning path to reach the target temperature was found to be important on the development of excess pore pressure at near and slightly below-freezing temperatures.  相似文献   
46.
The dynamics of sediment transport capacity in gravel‐bed rivers is critical to understanding the formation and preservation of fluvial landforms and formulating sediment‐routing models in drainage systems. We examine transport‐storage relations during cycles of aggradation and degradation by augmenting observations of three events of channel aggradation and degradation in Cuneo Creek, a steep (3%) gravel‐bed channel in northern California, with measurements from a series of flume runs modeling those events. An armored, single‐thread channel was formed before feed rates were increased in each aggradation run. Output rates increased as the channel became finer and later widened, steepened, and braided. After feed rates were cut, output rates remained high or increased in early stages of degradation as the incising channel remained fine‐grained, and later decreased as armoring intensified. If equilibrium was not reached before sediment feed rate was cut, then a rapid transition from a braided channel to a single‐thread channel caused output rates for a given storage volume to be higher during degradation than during aggradation. Variations in channel morphology, and surface bed texture during runs that modeled the three cycles of aggradation and degradation were similar to those observed in Cuneo Creek and provide confidence in interpretations of the history of change: Cuneo Creek aggraded rapidly as it widened, shallowed, and braided, then degraded rapidly before armoring stabilized the channel. Such morphology‐driven changes in transport capacity may explain the formation of flood terraces in proximal channels. Transport‐storage relations can be expected to vary between aggradation and degradation and be influenced by channel conditions at the onset of changes in sediment supply. Published in 2011. This article is a US Government work and is in the public domain in the USA.  相似文献   
47.
Social vulnerability is a term that has been widely used in the natural hazards literature for quite a few years now. Yet, regardless of how scholars define the term, the approaches and indicators they use remain contested. This article presents findings from social vulnerability assessments conducted in different case studies of flood events in Europe (Germany, Italy and the UK). The case studies relied upon a common set of comparable indicators, but they also adopted a context-sensitive, qualitative approach. A shared finding across the case studies was that it was not possible to identify a common set of socio-economic–demographic indicators to explain social vulnerability of groups and/or individuals for all phases of the disastrous events. Similarly, network-related indicators as well as location- and event-specific indicators did not have the relevance we expected them to have. The results underline that vulnerability is a product of specific spatial, socio-economic–demographic, cultural and institutional contexts imposing not only specific challenges to cross-country research concerning social vulnerability to flooding but also to attempts at assessing social vulnerability in general. The study ends with some reflections upon the methodological, practical and theoretical implications of our findings.  相似文献   
48.
This paper offers a critical review of modeling practice in the field of integrated assessment of climate change and ways forward. Past efforts in integrated assessment have concentrated on developing baseline trajectories of emissions and mitigation scenario analyses. A key missing component in Integrated Assessment Models (IAMs) is the representation of climate impacts and adaptation responses. In this paper, we identify key biases that are introduced when climate impacts and adaptation responses are omitted from the analysis and review the state of modeling studies that attempt to capture these feedbacks. A common problem in these IAM studies is the lack of connection with empirical studies. We therefore also review the state of the empirical work on climate impacts and identify ways that this connection could be improved.  相似文献   
49.
Chau  Vu Ngoc  Cassells  Sue  Holland  John 《Natural Hazards》2015,75(2):1747-1765
Natural Hazards - Quang Nam province, central Vietnam, is situated within the tropical monsoon and typhoon zone of south-east Asia and is susceptible to extreme floods. Historical water level data...  相似文献   
50.
Cumming  Gabriel  Campbell  Lisa  Norwood  Carla  Ranger  Sue  Richardson  Peter  Sanghera  Amdeep 《GeoJournal》2021,87(2):209-221

Stakeholders in natural resource management decisions are also multifaceted individuals and members of communities; as such, they bring complex histories, experiences, values, aspirations, and relationships to public participation processes. When these processes fail to take this social context into account, multiple problems can result, including a perceived lack of process trustworthiness; perceived focus on issues that seem immaterial or irrelevant; failure to equitably represent and take account of diverse voices; and failure to engage participants in productive dialogue. In this article we evaluate the Community Voice Method (CVM) as a way of addressing those problems by better situating public participation in place. CVM is a mixed-method approach to public participation in which stakeholders are interviewed and the interview data is presented through a film, which is then screened at public meetings to catalyze dialogue. We draw on 14 years of CVM projects addressing natural resource management issues in the United States, the United Kingdom, and the Caribbean. Through an overview of nine projects and their results, and more in-depth consideration of three, we elucidate how this method fosters trustworthy, relevant, representative, and productive public participation that has resulted in community capacity-building, institutional capacity-building, and stakeholder-guided policymaking.

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