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81.
ABSTRACT

Despite a notable increase in the literature on community resilience, the notion of ‘community’ remains underproblematised. This is evident within flood risk management (FRM) literature, in which the understanding and roles of communities may be acknowledged but seldom discussed in any detail. The purpose of the article is to demonstrate how community networks are configured by different actors, whose roles and responsibilities span spatial scales within the context of FRM. Accordingly, the authors analyse findings from semi-structured interviews, policy documents, and household surveys from two flood prone areas in Finnish Lapland. The analysis reveals that the ways in which authorities, civil society, and informal actors take on multiple roles are intertwined and form different types of networks. By implication, the configuration of community is fuzzy, elusive and situated, and not confined to a fixed spatiality. The authors discuss the implications of the complex nature of community for FRM specifically, and for community resilience more broadly. They conclude that an analysis of different actors across scales contributes to an understanding of the configuration of community, including community resilience, and how the meaning of community takes shape according to the differing aims of FRM in combination with differing geographical settings.  相似文献   
82.
Travel behavior of the present generation of youths is being increasingly explored due to their relevance in shaping future accessibility needs and mobility habits. The present study offers an original perspective on this topic by identifying territorial disparities that emerge in youth mobility patterns in rural and urban areas. Unlike most previous research, we propose taking a global view on mobility by analyzing all trip purposes and transportation modes. This is conducted by analyzing a comprehensive mobility survey in the Barcelona Metropolitan Region, which provides data on mobility engagement, trip purposes, modal split, travel times and territorial differences. In general, youngsters account for larger daily travel times than older adults, present a higher attachment to public transportation and walk less on a daily basis. These differences are enhanced in rural territories, where while older adults overcome accessibility issues with higher use of the private vehicle, youngsters are more likely to invest larger travel times on transit.  相似文献   
83.
We present a high-resolution, multiproxy reconstruction of the depositional history of Lake Arreo, northern Spain, for the last 60 years. We conducted sedimentological, geochemical and diatom analyses in short cores and made a detailed comparison with regional instrumental climate data (1952–2007), limnological monitoring of the lake (1992–2008) and recent land use changes that affect the lake catchment. Chronology is based on “floating” discontinuous varve counts and 137Cs and 14C dates. Four periods were identified in the Lake Arreo recent history: (1) prior to 1963, varved facies intercalated with fine turbidite deposits, and diatom assemblages dominated by Cyclotella taxa indicate predominantly meromictic conditions, (2) from 1964 to 1978, permanent anoxia persisted in bottom waters, as shown by similar facies and diatom assemblages as before, though detrital layers were coarser, (3) from 1979 to 1994, sediment delivery to the lake increased and laminated, clastic facies were deposited, and (4) from 1995 to 2008, dominance of massive facies and an increase in Fragilaria tenera and Achnanthes minutissima reflect relatively lower lake levels, less frequent bottom anoxia with more frequent water column mixing, similar to modern conditions. The period 1952–1979 was a time of meromixis and varved facies deposition, and was characterized by higher rainfall and less intense agricultural pressure in the watershed. There were two short humid periods (1992–1993 and 1996–1998) when monitoring data show more anoxic weeks per year and relatively higher lake levels. Increased cultivation of small landholdings in 1963, and particularly after 1979, caused a large increase in sediment delivery to the lake. The inferred lake evolution is in agreement with monitoring data that suggest a transition from dominantly meromictic conditions prior to 1993–1994 to a predominantly monomictic pattern of circulation since then, particularly after 2000. The synergistic effects of intensive water extraction for irrigation and lower rainfall since 1979, and particularly since 1994, brought the long period of meromictic conditions in Lake Arreo to an end. Water balance and sediment delivery to the lake are dominant factors that control the limnological and mixing conditions in Lake Arreo and they must be considered in management and restoration plans.  相似文献   
84.
Zusammenfassung Die Beziehung zwischen äquatorialen Konvektionsregen und der Meereshöhe wird am Beispiel der Südabdachung der Haputale Range auf Ceylon (etwa 7° nördl. Br. und rund 1400 m Höhenunterschied) untersucht. Auf der Grundlage unveröffentlichter Niederschlagsmessungen von 21 Stationen, vorwiegend Teeplantagen, für die Periode von 1951–1965 wird die Änderung der Niederschlagsmenge mit der Höhe an Hand der mittleren jährlichen und mittleren monatlichen Niederschlagsmengen diskutiert. Hierbei ergibt sich im Jahresmittel und in den Monaten mit vorwiegend konvektiver Niederschlagsbildung — das sind die Intermonsunmonate März, April und Mai sowie Oktober und November —, daß nach anfänglicher Zunahme des Niederschlags mit wachsender Höhe oberhalb einer kritischen Höhenlage zwischen 900–1400 m NN eine stetige Abnahme des Niederschlags eintritt.
Summary The relationship between equatorial convective rain and altitude above sea-level is investigated taking the southern slope of the Haputale Range in Ceylon (7° N, about 1400 m range of altitude) as an example. On the basis of unpublished precipitation observations of 21 stations, most of them on tea-estates, from the period 1951 to 1965 the variation of the amount of precipitation with altitude is discussed using mean annual and mean monthly precipitation totals. It appears that in the annual mean and during the months with prevailing convective rain — these are the intermonsoonal months March, April, May and October, November — the precipitation totals increase with altitude up to a critical level between 900 and 1400 m a.s.l. and then decrease again monotonically.

Résumé On examine ici la relation existant entre les précipitations équatoriales de convection d'une part et l'altitude d'autre part. Pour ce faire, on se sert de l'exemple offert par le versant sud de l'Haputale Range de Ceylan (situé à environ 7° de latitude N et présentant une différence d'altitude de 1400 m environ). Sur la base de mesures non publiées des précipitations — mesures effectuées de 1951 à 1965 à 21 stations, en majeure partie des plantations de thé — on discute les modifications que subissent les sommes de précipitations avec l'altitude. Dans ce but, on utilise les moyennes annuelles et mensuelles de cet élément. Il en résulte que les précipitations augmentent tout d'abord avec l'altitude et cela jusqu'à une zone critique située entre 900 et 1400 m. Au-dessus, les précipitations diminuent de nouveau régulièrement. Cette constatation est valable aussi bien pour la moyenne annuelle que pour les mois caractérisés avant tout par des précipitations d'origine convective c'est à dire ceux qui se situent entre les périodes de mousson (mars, avril, mai, octobre et novembre).


Mit 4 Abbildungen  相似文献   
85.
Karabash (52°2 N, 60°10 E) is a copper smelting town in the southern Ural Mountains of Russia. The town is affected by sulphur dioxide emissions and deposition of metal-rich particulates from the smelter, acid drainage from old mine workings, and leachates from disused waste dumps and tailings dams. The close proximity of houses to these sources of pollution is of concern to human health and has devastated terrestrial vegetation in the environs. The environmental impact of the smelter on lakes in the area has been assessed using chironomids. Short sediment cores were taken from 16 lakes within a 50 km radius of the smelter and the composition of the chironomid fauna from the bottom of each core, representing conditions prior to the commissioning of the smelter in 1910, was compared with the present chironomid fauna in the surface sediments. Redundancy analysis (RDA) showed that changes in the chironomid fauna of most lakes were driven by trophic change, independent of the industrial activity. Lakes and ponds adjacent to the smelter and waste dumps, which directly receive contaminated waters were devoid of macro- and mesofauna and flora, but there is no evidence that other lakes have been severely impacted by smelter emissions. Local geology ensures that the lakes are well-buffered to the effects of acid deposition which will limit the bioavailability of metals in the water column and sediment.  相似文献   
86.
87.
Résumé Les observations de deux stations situées à l'entrée de la vallée du Rhône et à l'intérieur de celle-ci permettent de déterminer dans une certaine mesure comment l'air froid pénètre dans cette longue vallée des Alpes suisses. L'accès se fait beaucoup plus souvent par-dessus les montagnes de l'Ouest ou du Nord que par le chenal de la vallée seulement.
Summary The observations of two stations at the entrance and in the interior of the Rhône valley allow to a certain degree to determine how cold air penetrates this long extended valley of the Swiss Alps. The influx of air takes much more frequently place over the mountains in the West and North than through the trough of the valley.

Zusammenfassung Die Beobachtungen von zwei Stationen, die am Eingang und im Inneren des Rhonetals gelegen sind, erlauben einigermaßen festzustellen, wie die Kaltluft in dieses langgestreckte Tal der Schweizeralpen eindringt. Dabei erfolgt der Luftzustrom viel häufiger über die Berge im W und N als ausschließlich durch die Talrinne.


Avec 1 Figure  相似文献   
88.
This study presents an analysis of climate-change impacts on the water resources of two basins located in northern France, by integrating four sources of uncertainty: climate modelling, hydrological modelling, downscaling methods, and emission scenarios. The analysis focused on the evolution of the water budget, the river discharges and piezometric heads. Seven hydrological models were used, from lumped rainfall-discharge to distributed hydrogeological models, and led to quite different estimates of the water-balance components. One of the hydrological models, CLSM, was found to be unable to simulate the increased water stress and was, thus, considered as an outlier even though it gave fair results for the present day compared to observations. Although there were large differences in the results between the models, there was a marked tendency towards a decrease of the water resource in the rivers and aquifers (on average in 2050 about ?14 % and ?2.5 m, respectively), associated with global warming and a reduction in annual precipitation (on average in 2050 +2.1 K and ?3 %, respectively). The uncertainty associated to climate models was shown to clearly dominate, while the three others were about the same order of magnitude and 3–4 times lower. In terms of impact, the results found in this work are rather different from those obtained in a previous study, even though two of the hydrological models and one of the climate models were used in both studies. This emphasizes the need for a survey of the climatic-change impact on the water resource.  相似文献   
89.
Bottom-up and top-down models are used to support climate policies, to identify the options required to meet GHG abatement targets and to evaluate their economic impact. Some studies have shown that the GHG mitigation options provided by economic top-down and technological bottom-up models tend to vary. One reason for this is that these models tend to use different baseline scenarios. The bottom-up TIMES_PT and the top-down computable general equilibrium GEM-E3_PT models are examined using a common baseline scenario to calibrate them, and the extend of their different mitigation options and its relevant to domestic policy making are assessed. Three low-carbon scenarios for Portugal until 2050 are generated, each with different GHG reduction targets. Both models suggest close mitigation options and locate the largest mitigation potential to energy supply. However, the models suggest different mitigation options for the end-use sectors: GEM-E3_PT focuses more on energy efficiency, while TIMES_PT relies on decrease carbon intensity due to a shift to electricity. Although a common baseline scenario cannot be ignored, the models’ inherent characteristics are the main factor for the different outcomes, thereby highlighting different mitigation options.

Policy relevance

The relevance of modelling tools used to support the design of domestic climate policies is assessed by evaluating the mitigation options suggested by a bottom-up and a top-down model. The different outcomes of each model are significant for climate policy design since each suggest different mitigation options like end-use energy efficiency and the promotion of low-carbon technologies. Policy makers should carefully select the modelling tool used to support their policies. The specific modelling structures of each model make them more appropriate to address certain policy questions than others. Using both modelling approaches for policy support can therefore bring added value and result in more robust climate policy design. Although the results are specific for Portugal, the insights provided by the analysis of both models can be extended to, and used in the climate policy decisions of, other countries.  相似文献   
90.
ABSTRACT

The continuous submission and scaling-up of Nationally Determined Contributions (NDCs) constitutes a key feature of the Paris Agreement. In their NDCs, states propose governance mechanisms for implementation of climate action, in turn distinguishing appropriate roles for the state in climate governance. Clarity on Parties’ suggested roles for the state makes explicit assumptions on the premise of climate policy, in turn contributing to enhanced transparency in negotiations on the scaling-up of NDCs. This also speaks to ongoing debates on roles for the state in climate governance literature. This article identifies the governance mechanisms proposed by states in their NDCs and the roles for the state envisioned by those governance mechanisms, and also examines how cross-national patterns of roles for the state break or converge with conventional patterns of international politics. The analysis shows that states propose a plurality of roles, which to different extents may be complementary or conflictual. We conclude that income, region, and the Annexes under the United Nations Framework Convention on Climate Change (UNFCCC) are important for understanding suggested roles for the state, but that there are nuances to be further explored. We argue that this paper has three key findings: i) a majority of states rely on market mechanisms to implement their NDCs while rules on implementation and assessment of market mechanisms are still an outstanding issue in the negotiations, meaning that resolving this issue will be essential; ii) the process for evaluating and assessing qualitative governance mechanisms needs to be specified; and iii) increased awareness of differing views on the state’s roles makes explicit different perspectives on what constitutes an ambitious and legitimate contribution to combating climate change.

Key policy insights
  • A majority of states (> 75%) envision the state as regulator (creating and strengthening legislation), market facilitator (creating and maintaining market structures), or facilitator (creating more favourable material conditions for climate-friendly behaviour).

  • Greater awareness of differing views on roles for the state can increase understanding of different perspectives on ambition and legitimacy of contributions, in turn facilitating trust in negotiations.

  • A distinction between substantive and procedural qualitative governance mechanisms and their function and interaction would facilitate the stocktaking dialogues.

  相似文献   
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