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921.
This article tells the story of long-lasting and ongoing struggles surrounding the construction plans for a major reservoir on the headwaters of the Kemi River in the Finnish Province of Lapland. A point of contention since the beginning of hydropower development on the river in the mid twentieth century, the reservoir project has been promoted and abandoned multiple times in waves of land purchasing, legal procedures, opposition campaigns, and the delineation of nature reserves. Despite a Finnish Supreme Administrative Court ruling officially setting an end to the project, it never entirely left public discourse and is currently being re-negotiated in slightly adapted form. Articulating voices and documenting practices of riverbank inhabitants, activists and hydro electricity managers, this article presents the struggle as multiple modes of heterogeneous engineering, where both proponents and opponents work towards creating different realities. The article develops the metaphor of heterogeneous engineering by drawing attention to three temporal dimensions central to the reservoir struggle: moments, which refer to the situated emergence of practices and strategies; futures, which speak to the attempts to build and contest expectations regarding conflicting projects; and durations, which consider the cumulative aspects of a decades-long struggle on people and landscapes. Thereby, the article contributes to discussions on making, planning and environmental management, and illustrates ways of studying these processes as situated practices in relation to time.  相似文献   
922.
People’s reasons for visiting national parks have been well researched. So too have their park activities and how diverse activities potentially affect visitors’ park experiences (e.g. perceptions of overcrowding). Far less research has examined how park users’ environmental values might affect their perceptions of other users and the appropriateness of different activities – a potential source of conflict. Relationships between personal environmental values and environmental and social perceptions are complex and interactive in the context of park visitation. Visitors’ encounters with other users can powerfully affect their experience and enjoyment of parks, in turn reflecting such factors as values-related expectations and judgments in the context of national parks. Personal and social values may also play an important role in influencing whether different activities are perceived as ‘out of place’ in the context of national park place meaning, yet the conceptualization of values within geographic literature on parks remains comparatively weak.This paper utilizes a definition of values, derived from a concise review of the geography and social psychology literatures, to explain the results of survey research we undertook within national parks in Queensland, Australia. We use a ‘values-behavior hierarchy’ conceptual framework to consider how the personal environmental values of a sample of park visitors (n = 404) potentially affected patterns of park visitation, user activities, and user conflicts. Findings suggest that visitors’ environmental values shaped how they perceived other park users and the appropriateness of their activities. This has international implications for geographic research and other disciplines and professions involved in national park visitation, park use, and human impacts, on and of these powerful places.  相似文献   
923.
A rapidly growing literature interrogates the social and economic impacts of various Reducing Emissions from Deforestation and Forest Degradation (REDD+) schemes in Sub-Saharan Africa. Less often, however, have scholars examined the necessary corollary of such initiatives; that is, both new and enhanced law enforcement initiatives to combat the global trade in illegal forest products and secure property rights to conserved forests. Drawing upon recent consultative experiences for relevant multinational agencies in East Africa, we critically analyze the emergent features of this additional ‘dark side’ of REDD+, highlighting in particular both its potential for ‘leakage’ effects on adjacent jurisdictions and deleterious implications for forest-dependent communities. Specifically, we highlight the ways in which such activities threaten to conflate illegal with informal trade in forest products; the ways in which they are potentially ill-suited for addressing the trade in charcoal as opposed to the trade in timber; and the incentives that they may provide for states to further marginalize indigenous forest-dwelling populations in the region. In doing so, we argue that this nascent synthesis of REDD+ and transnational law enforcement threatens to contribute significantly and regressively to the broader securitization of conservation in Sub-Saharan Africa and elsewhere.  相似文献   
924.
It is widely accepted that environmental change can influence human migration. In particular, the environment plays a role in migration processes in drylands, in which environmental change—including increasing variability of rainfall, increasing frequency of droughts, chronic water shortage, and land degradation—can heavily influence migration. However, systematic large-scale studies of the relationship between environmental factors and human migration are rare, and a global, consistent picture of environmental drivers of migration is lacking. In this study, we sought to fill this gap by analysing spatial patterns of environmental drivers of migration in drylands by performing a cluster analysis on spatially explicit global data. In this analysis, we focused explicitly on precipitation, aridity, drought, land degradation, soil constraints, and availability of cropland and pastures as potential environmental drivers of migration in drylands. In addition, we linked the identified clusters to two observed hotspots of out-migration—Burkina Faso and Northeast Brazil—to gauge the cluster results. Our results show that environmental drivers can be grouped into eight distinct clusters, and we identified the most severe environmental constraints for each cluster. These results suggest that out-migration—both in absolute and relative terms—occurs most frequently in a cluster that is constrained primarily by land degradation rather than water availability.  相似文献   
925.
A reliance on mathematical modelling is a defining feature of modern global environmental and public health governance. Initially hailed as the vanguard of a new era of rational policy-making, models are now habitually subject to critical analyses. Their quality, in other words, is routinely queried, yet what exactly is quality in this context? The prevailing paradigm views model quality as a multi-dimensional concept, encompassing technical dimensions (e.g. precision and bias), value judgments, problem-framing, treatment of “deep” uncertainties, and pragmatic features of particular decision contexts. Whilst those technical dimensions are relatively simple to characterise, the broader dimensions of quality are less easily formalised and as a result are difficult to take account of during model construction and evaluation. Here, we present a typology of governance regimes (risk-based, precautionary, adaptive and participatory) that helps make explicit what these broader dimensions of model quality are, and sketches out how the emphasis placed on them differs by regime type. We show that these regime types hold distinct positions on what constitutes sound evidence, on how that evidence should be used in policy-making, and to what social ends. As such, a model may be viewed within one regime as providing legitimate evidence for action, be down-weighted elsewhere for reflecting a flawed problem-framing, and outright rejected in another jurisdiction on the grounds that it does not cohere with the preferred ethical framework for decision-making. We illustrate these dynamics by applying our typology to a range of policy domains, emphasising both the disconnects that can occur, as well as the ways that modellers have adapted their practices to ensure that their evidence is brought to bear on policy problems across diverse regime types.  相似文献   
926.
Energy system pathways which are projected to deliver minimum possible deployment cost, combined with low Greenhouse Gas (GHG) emissions, are usually considered as ‘no-regrets’ options. However, the question remains whether such energy pathways present ‘no-regrets’ when also considering the wider environmental resource impacts, in particular those on land and water resources. This paper aims to determine whether the energy pathways of the UK’s Carbon Plan are environmental “no-regrets” options, defined in this study as simultaneously exhibiting low impact on land and water services resulting from resource appropriation for energy provision. This is accomplished by estimating the land area and water abstraction required by 2050 under the four pathways of the Carbon Plan with different scenarios for energy crop composition, yield, and power station locations. The outcomes are compared with defined limits for sustainable land appropriation and water abstraction.The results show that of the four Carbon Plan pathways, only the “Higher Renewables, more energy efficiency” pathway is an environmental “no-regrets” option, and that is only if deployment of power stations inland is limited. The study shows that policies for future low-carbon energy systems should be developed with awareness of wider environmental impacts. Failing to do this could lead to a setback in achieving GHG emission reductions goals, because of unforeseen additional competition between the energy sector and demand for land and water services in other sectors.  相似文献   
927.
The assessment of estuaries based on benthic communities is widely used to determine impacts caused by human pressure and is one of the required tools for the implementation of the European Water Framework Directive (WFD). Our study compared multimetric approaches (B-IBI and TICOR) to assess the benthic condition of three Portuguese estuaries (Mondego, Tejo, and Mira rivers) with different levels of natural and human induced stress. Benthic community condition was classified into quality status categories of the WFD and compared for consistency with a priori status categories based upon physical-chemical criteria. Both multimetric indices discriminated equally well between locations classified above or below the good status category but were unable to provide good separation between other quality classes (high/good, moderate, poor/bad). Metrics included in these indices are greatly affected by natural stress and we recommend the development of habitat-specific thresholds to increase the discriminatory ability of any benthic condition index.  相似文献   
928.
Toxic harmful algal bloom (HAB) occurrence is becoming more frequent and problematic in highly urbanized coastal zones. In summer 2005 along the urbanized Genoa coastline (Ligurian Sea, North western Mediterranean Sea), local first aid stations treated about 200 people, who all showed similar symptoms following exposure to marine aerosols. The link with proliferation of Ostreopsis ovata was made, and it highlighted for the first time, the risks that benthic HABs may represent in highly urbanised temperate areas. Subsequently, a specific monitoring plan was designed and implemented in the same area in July 2006, before the first signs of Ostreopsis proliferation were detected. Here we report on this quantification of an Ostreopsis ovata bloom in the Ligurian Sea. Cells were quantified both in the water column and in the epiphytic community on macrophytes. Our results suggest a role of sea water temperature and weather conditions in favouring bloom development.  相似文献   
929.
Economic valuation for the conservation of marine biodiversity   总被引:3,自引:0,他引:3  
Policy makers are increasingly recognising the role of environmental valuation to guide and support the management and conservation of biodiversity. This paper presents a goods and services approach to determine the economic value of marine biodiversity in the UK, with the aim of clarifying the role of valuation in the management of marine biodiversity. The goods and services resulting from UK marine biodiversity are detailed, and 8 of the 13 services are valued in monetary terms. It is found that a decline in UK marine biodiversity could result in a varying, and at present unpredictable, change in the provision of goods and services, including reduced resilience and resistance to change, declining marine environmental health, reduced fisheries potential, and loss of recreational opportunities. The results suggest that this approach can facilitate biodiversity management by enabling the optimal allocation of limited management resources and through raising awareness of the importance of marine biodiversity.  相似文献   
930.
This paper provides a status update on the development of the Swedish wave energy research area located close to Lysekil on the Swedish West coast. The Lysekil project is run by the Centre for Renewable Electric Energy Conversion at Uppsala University. The project was started in 2004 and currently has permission to run until the end of 2013. During this time period 10 grid-connected wave energy converters, 30 buoys for studies on environmental impact, and a surveillance tower for monitoring the interaction between waves and converters will be installed and studied. To date the research area holds one complete wave energy converter connected to a measuring station on shore via a sea cable, a Wave Rider? buoy for wave measurements, 25 buoys for studies on environmental impact, and a surveillance tower. The wave energy converter is based on a linear synchronous generator which is placed on the sea bed and driven by a heaving point absorber at the ocean surface. The converter is directly driven, i.e. it has no gearbox or other mechanical or hydraulic conversion system. This results in a simple and robust mechanical system, but also in a somewhat more complicated electrical system.  相似文献   
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