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851.
ABSTRACT: This paper considers the distribution of flood flows in the Upper Mississippi, Lower Missouri, and Illinois Rivers and their relationship to climatic indices. Global climate patterns including El Niño/Southern Oscillation, the Pacific Decadal Oscillation, and the North Atlantic Oscillation explained very little of the variations in flow peaks. However, large and statistically significant upward trends were found in many gauge records along the Upper Mississippi and Missouri Rivers: at Hermann on the Missouri River above the confluence with the Mississippi (p = 2 percent), at Hannibal on the Mississippi River (p < 0.1 percent), at Meredosia on the Illinois River (p = 0.7 percent), and at St. Louis on the Mississippi below the confluence of all three rivers (p = 1 percent). This challenges the traditional assumption that flood series are independent and identically distributed random variables and suggests that flood risk changes over time.  相似文献   
852.
ABSTRACT: This paper reports on the current assessment of climate impacts on water resources, including aquatic ecosystems, agricultural demands, and water management, in the U.S. Great Plains. Climate change in the region may have profound effects on agricultural users, aquatic ecosystems, and urban and industrial users alike. In the central Great Plains Region, the potential impacts of climate changes include changes in winter snowfall and snow-melt, growing season rainfall amounts and intensities, minimum winter temperature, and summer time average temperature. Specifically, results from general circulation models indicate that both annual average temperatures and total annual precipitation will increase over the region. However, the seasonal patterns are not uniform. The combined effect of these changes in weather patterns and average seasonal climate will affect numerous sectors critical to the economic, social and ecological welfare of this region. Research is needed to better address the current competition among the water needs of agriculture, urban and industrial uses, and natural ecosystems, and then to look at potential changes. These diverse demands on water needs in this region compound the difficulty in managing water use and projecting the impact of climate changes among the various critical sectors in this region.  相似文献   
853.
ABSTRACT: To fully take advantage of regional climate forecast information for agricultural applications, the relationship between divisional and station scale precipitation characteristics must be quantified. The spatial variability of monthly precipitation is assumed to consist of two components: a systematic and a random component. The systematic component is defined by differences in long-term mean precipitation between stations within a climate division, and the random component by differences between station and divisional standardized values. For the Central Climate Division of Oklahoma, the systematic component has a positive precipitation gradient from west to east with a slope ranging between 3 to 16 mm of precipitation per 100 km depending on the month of the year. On the other hand, the random component ranges between 27 to 48 percent of the mean temporal variation of the monthly precipitation. This significant random spatial variability leads to large localized departures from divisional values, and clearly demonstrates the critical influence of the random component in the utilization of divisional climate forecasts for local agricultural applications. The results of this study also provide an uncertainty range for local monthly precipitation projections that are derived from divisional climate information.  相似文献   
854.
ABSTRACT: The effects of potential climate change on mean annual runoff in the conterminous United States (U.S.) are examined using a simple water-balance model and output from two atmospheric general circulation models (GCMs). The two GCMs are from the Canadian Centre for Climate Prediction and Analysis (CCC) and the Hadley Centre for Climate Prediction and Research (HAD). In general, the CCC GCM climate results in decreases in runoff for the conterminous U.S., and the HAD GCM climate produces increases in runoff. These estimated changes in runoff primarily are the result of estimated changes in precipitation. The changes in mean annual runoff, however, mostly are smaller than the decade-to-decade variability in GCM-based mean annual runoff and errors in GCM-based runoff. The differences in simulated runoff between the two GCMs, together with decade-to-decade variability and errors in GCM-based runoff, cause the estimates of changes in runoff to be uncertain and unreliable.  相似文献   
855.
Conservation of biodiversity relies heavily on protected areas but their role and effectiveness under a warming climate is still debated. We estimated the climate-driven changes in the temperature niche compositions of bird communities inside and outside protected areas in southern Canada. We hypothesized that communities inside protected areas include a higher proportion of cold-dwelling species than communities outside protected areas. We also hypothesized that communities shift to warm-dwelling species more slowly inside protected areas than outside. To study community changes, we used large-scale and long-term (1997–2019) data from the Breeding Bird Survey of Canada. To describe the temperature niche compositions of bird communities, we calculated the community temperature index (CTI) annually for each community inside and outside protected areas. Generally, warm-dwelling species dominated communities with high CTI values. We modeled temporal changes in CTI as a function of protection status with linear mixed-effect models. We also determined which species contributed most to the temporal changes in CTI with a jackknife approach. As anticipated, CTI was lower inside protected areas than outside. However, contrary to our expectation, CTI increased faster over time inside than outside protected areas and warm-dwelling species contributed most to CTI change inside protected areas. These results highlight the ubiquitous impacts of climate warming. Currently, protected areas can aid cold-dwelling species by providing habitat, but as the climate warms, the communities’ temperature compositions inside protected areas quickly begin to resemble those outside protected areas, suggesting that protected areas delay the impacts of climate warming on cold-dwelling species.  相似文献   
856.
The Common Agricultural Policy (CAP) is the European Union's main instrument for agricultural planning, with a new reform approved for 2023–2027. The CAP intends to align with the European Green Deal (EGD), a set of policy initiatives underpinning sustainable development and climate neutrality in the European Union (EU), but several flaws cast doubts about the compatibility of the objectives of these 2 policies. We reviewed recent literature on the potential of CAP environmental objectives for integration with the EGD: protection of biodiversity, climate change mitigation and adaptation, and sustainable management of natural resources. The CAP lacks appropriate planning measures, furthering instead risks to biodiversity and ecosystem services driven by landscape and biotic homogenization. Funding allocation mechanisms are not tailored to mitigate agricultural emissions, decreasing the efficiency of climate mitigation actions. The legislation subsidies farmers making extensive use of synthetic inputs without adequately supporting organic production, hindering the transition toward sustainable practices. We recommend proper control mechanisms be introduced in CAP Strategic Plans from each member state to ensure the EU is set on a sustainable production and consumption path. These include proportional assignment of funds to each CAP objective, quantitative targets to set goals and evidence-based interventions, and relevant indicators to facilitate effective monitoring of environmental performance. Both the CAP and the EGD should maintain ambitious environmental commitments in the face of crisis to avoid further degradation of the natural resources on which production systems stand.  相似文献   
857.
Climate warming can substantially impact embryonic development and juvenile growth in oviparous species. Estimating the overall impacts of climate warming on oviparous reproduction is difficult because egg-laying events happen throughout the reproductive season. Successful egg laying requires the completion of embryonic development as well as hatching timing conducive to offspring survival and energy accumulation. We propose a new metric—egg-laying opportunity (EO)—to estimate the annual hours during which a clutch of freshly laid eggs yields surviving offspring that store sufficient energy for overwintering. We estimated the EO within the distribution of a model species, Sceloporus undulatus, under recent climate condition and a climate-warming scenario by combining microclimate data, developmental functions, and biophysical models. We predicted that EO will decline as the climate warms at 74.8% of 11,407 sites. Decreasing hatching success and offspring energy accounted for more lost EO hours (72.6% and 72.9%) than the occurrence of offspring heat stress (59.9%). Nesting deeper (at a depth of 12 cm) may be a more effective behavioral adjustment for retaining EO than using shadier (50% shade) nests because the former fully mitigated the decline of EO under the considered warming scenario at more sites (66.1%) than the latter (28.3%). We advocate for the use of EO in predicting the impacts of climate warming on oviparous animals because it encapsulates the integrative impacts of climate warming on all stages of reproductive life history.  相似文献   
858.
The current discussion of anticipated climate change impacts and future sea level rise is particularly relevant to small island states. An increase in natural hazards, such as floods and storm waves, is likely to have a devastating impact on small islands' coastlines, severely affecting targeted sustainable development. Coastal erosion, notably human‐induced erosion, has been an ongoing threat to small island biodiversity, resources, infrastructure, and settlements, as well as society at large. In the context of climate change, the problem of coastal erosion and the debate surrounding it is gaining momentum. Before attributing associated impacts to climate change, current human activities need to be analysed, focusing not only on geomorphological and climatological aspects, but also on political and traditional cultural frameworks. The objective of this paper is to demonstrate the importance of the social‐political‐ecological systems analysis for adaptation strategies, and thus for future sustainable development. Coastal use is based on human constructs of the coast, as well as local perceptions and values ascribed to the coast. We use the case study of Anjouan, Comoros to differentiate between constructive and destructive practices on the coast, from both a mental and technical perspective. Beach erosion is described as more than a resource problem that manifests itself locally rather than nationally. Divergent political scales of interest impact future development as much as local action. Local action is not least framed by mental contribution and attribution of coasts as places for living, recreation and resource use. The present case study demonstrates that mental constructs of coasts as valuable areas can, in some cases, lead to the protection and preservation of beaches by initiatives of collective action. At the same time, local communities see the negative impacts of sand mining as causes of coastal erosion and, therefore, it is difficult to mobilize them to adapt to climate change and sea level rise.  相似文献   
859.
Yasuo Takao 《Local Environment》2016,21(9):1100-1117
The aim of the present article is to examine the importance of public participation in the production and use of environmental science, with special reference to “expert citizens” who can facilitate and mediate between expert knowledge and lay people. The study of expert citizens is largely unexplored in Japan's environmental policy. As uncertainty, inherent in the complexity of environmental science, increases, there are calls for refashioning expert knowledge into a more citizen–expert interactive governance. In the USA, the way that lay people can participate in scientific knowledge application and policy-making is organised through grassroots and national environmental organisations, such as the National Resources Defense Council. In Japan, such professional associations that build networks of interaction with scientific experts, policy-makers, interest groups and the media, have yet to emerge on a wider scale. Nonetheless, voluntary citizens individually or collectively have developed their expertise over many years and have begun to play an intermediary role at the local level. This article will analyse the potential roles of expert citizens by conducting the case studies of two Japanese localities, Shiki and Joyo cities.  相似文献   
860.
Nationally Appropriate Mitigation Actions (NAMAs) were proposed as a policy framework that could provide middle ground for meeting both the development and mitigation objectives in developing countries. While South Africa engaged actively with the NAMA terminology in the United Nations Framework Convention on Climate Change negotiations, its engagement at the domestic level has been rather lacklustre. This presents an interesting paradox. The paper studies the interplay of international norms embodied in NAMAs with South Africa's domestic policy process. Disengagement and contestation around NAMAs in South Africa is played out at three stages: decision-making stage where the symptoms surrounding this contestation first emerge; policy formulation stage where NAMAs have to not only align with the National Development Plan but also compete with a predilection for domestically familiar terminology of flagships under the national climate policy; and finally the broader agenda-setting stage of policy process, where NAMAs have to prove useful in not only pursuing the developmental state agenda but also in tackling the underlying material factors that represent country's economic dependency on fossil fuels. NAMAs faced combined resistance from ideas and interests in various degrees at all these stages resulting in their disengagement.  相似文献   
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