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991.
Regional Environmental Change - Historical land use may shape landscapes for centuries into the future, but it remains unclear how much land-use legacies affect contemporary land use. Knowing for...  相似文献   
992.
Rural and remote areas of countries such as Australia and the United States are less well‐resourced and often poorer than their city counterparts. When a disaster strikes, therefore, their long‐term recovery can be impeded by being situated ‘over the horizon'. Nonetheless, they are likely to enjoy higher social capital, with ‘locals’ banding together to help restore economic and social life in the wake of a calamitous incident. At the same time, a repeat of extreme events, springing in part from alteration to the landscape through intense human occupation, threatens to derail sustainable recovery processes everywhere, suggesting that renewed emphasis needs to be placed on preparedness. Improved metrics are also required, spanning both pre‐ and post‐disaster phases, to determine effectiveness. Moreover, a focus on the ‘hardening’ of towns offers a better return in limiting damage and potentially hastens the speed of recovery should these places later fall victim to extreme events.  相似文献   
993.
This study investigates the strategic antecedents of operational agility in humanitarian logistics. It began by identifying the particular actions to be taken at the strategic level of a humanitarian organisation to support field‐level agility. Next, quantitative data (n=59) were collected on four strategic‐level capabilities (being purposeful, action‐focused, collaborative, and learning‐oriented) and on operational agility (field responsiveness and flexibility). Using a quantitative analysis, the study tested the relationship between organisational capacity building and operational agility and found that the four strategic‐level capabilities are fundamental building blocks of agility. Collectively they account for 52 per cent of the ability of humanitarian logisticians to deal with ongoing changes and disruptions in the field. This study emphasises the need for researchers and practitioners to embrace a broader perspective of agility in humanitarian logistics. In addition, it highlights the inherently strategic nature of agility, the development of which involves focusing simultaneously on multiple drivers.  相似文献   
994.
Protecting our water resources in terms of quality and quantity is considered one of the big challenges of the twenty-first century, which requires global and multidisciplinary solutions. A specific threat to water resources, in particular, is the increased occurrence and frequency of flood events due to climate change which has significant environmental and socioeconomic impacts. In addition to climate change, flooding (or subsequent erosion and run-off) may be exacerbated by, or result from, land use activities, obstruction of waterways, or urbanization of floodplains, as well as mining and other anthropogenic activities that alter natural flow regimes. Climate change and other anthropogenic induced flood events threaten the quantity of water as well as the quality of ecosystems and associated aquatic life. The quality of water can be significantly reduced through the unintentional distribution of pollutants, damage of infrastructure, and distribution of sediments and suspended materials during flood events. To understand and predict how flood events and associated distribution of pollutants may impact ecosystem and human health, as well as infrastructure, large-scale interdisciplinary collaborative efforts are required, which involve ecotoxicologists, hydrologists, chemists, geoscientists, water engineers, and socioeconomists. The research network “project house water” consists of a number of experts from a wide range of disciplines and was established to improve our current understanding of flood events and associated societal and environmental impacts. The concept of project house and similar seed fund and boost fund projects was established by the RWTH Aachen University within the framework of the German excellence initiative with support of the German research foundation (DFG) to promote and fund interdisciplinary research projects and provide a platform for scientists to collaborate on innovative, challenging research. Project house water consists of six proof-of-concept studies in very diverse and interdisciplinary areas of research (ecotoxicology, water, and chemical process engineering, geography, sociology, economy). The goal is to promote and foster high-quality research in the areas of water research and flood-risk assessments that combine and build off-laboratory experiments with modeling, monitoring, and surveys, as well as the use of applied methods and techniques across a variety of disciplines.  相似文献   
995.
Substantial percentage of world food production depends on pollinating service of honeybees that directly depends on their health status. Among other factors, the success of bee colonies depends on health of developed larvae. The crucial phase of larval development is the first 6 days after hatching when a worker larva grows exponentially and larvae are potentially exposed to xenobiotics via diet. In the present study, we determined the lethal concentration LC50 (72 h) following single dietary exposure of honeybee larvae to formetanate under laboratory conditions, being also the first report available in scientific literature. Activities of antioxidant enzymes, superoxide dismutase (SOD), catalase (CAT) and glutathione-S-transferase (GST) were also measured in the homogenates of in vitro reared honeybee larvae after single formetanate exposure. Decreased specific activity of SOD and increased activities of CAT and GST suggest the induction of oxidative stress. Higher levels of thiobarbituric reactive species in all samples supported this fact. Comparing determined larval toxicity (LC50 of 206.01 mg a.i./kg diet) with adult toxicity data, we can suppose that the larvae may be less sensitive to formetanate than the adult bees.  相似文献   
996.
Environmental Science and Pollution Research - Trichloroethylene (TCE) is a widespread soil and groundwater pollutant and clean-up is often problematic and expensive. Phytoremediation may be a...  相似文献   
997.

Containment of genetically modified (GM) microorganisms such as Escherichia coli is a legal requirement to protect the environment from an unintended release and to avoid horizontal gene transfer (HGT) of recombinant DNA to native bacteria. In this study, we sampled the laboratory wastewater (LWW) at a large Swiss university from three sources over 2 years and cultured ampicillin-resistant, presumptive GM E. coli. From a total of 285 samples, 127 contained presumptive GM E. coli (45%) at a mean concentration of 2.8 × 102 CFU/ml. Plasmid DNA of 11 unique clones was partially or entirely sequenced. All consisted of cloning vectors harboring research-specific inserts. To estimate the chance of HGT between GM E. coli and native bacteria in LWW, we identified taxa representative for the bacterial community in LWW using 16S rRNA amplicon sequencing and measured conjugation frequencies of E. coli with five LWW isolates. At optimal conjugation conditions, frequencies were between 3.4 × 10−3 and 2.4 × 10−5. Given the absence of transferable broad-host range plasmids and suboptimal conjugation conditions in the LWW system, we conclude that the chance of HGT is relatively low. Still, this study shows that the implementation of robust containment measures is key to avoid the escape of GM microorganisms.

  相似文献   
998.
Urban green/blue spaces are put under pressure as urban areas grow, develop and evolve. It is increasingly recognized, however, that green/blue spaces provide important ecosystem services, stimulate higher real estate prices and prevent flooding problems. This paper aims to assess and compare the socio-economic impacts of potential green/blue space, urban residential and road infrastructure development scenarios in the Lyon Confluence project area (France), using the Sustainable Urbanizing Landscape Development (SULD) hedonic pricing simulation model. Results show four major tendencies regarding the value-added of green/blue spaces in urban landscapes: (1) cities become more compact; (2) population densities increase; (3) real estate values rise; and (4) demographic distribution patterns change. The magnitude of these impacts depends, however, on the quality and size of the intervention, the social classes attracted to the intervention area and on the location of the intervention relative to existing residential areas, urban centres, road infrastructure and environmental amenities.  相似文献   
999.
Control of wild animals may give rise to controversy, as is seen in the case of badger control to manage TB in cattle in the UK. However, it is striking that concerns about the potential suffering of the affected animals themselves are often given little attention or completely ignored in policies aimed at dealing with wild animals. McCulloch and Reiss argue that this could be remedied by means of a “mandatory application of formal and systematic Animal Welfare Impact Assessment (AWIA)”. Optimistically, they consider that an AWIA could help to resolve controversies involving wild animals. The aim of this paper is to evaluate the potential of AWIA. We begin by showing how ideas akin to AWIA already play a significant role in other animal ethics controversies, particularly those concerning laboratory animal use and livestock production; and we bring in lessons learnt from these controversies. Then we comment on the suggested development and application of AWIA in the case of badger control. Finally, we discuss the prospects of applying AWIA to other sorts of wild animal controversy. We argue that the AIWA, as developed by McCulloch and Reiss, relies on several dubious premises, including that killing is a welfare issue. Furthermore, we argue that AWIA is unlikely to prevent serious moral disagreements over how to weigh concerns about wild animals against priorities in human health, the health of domestic and farm animals, and biodiversity, but that it may nonetheless serve to limit harms imposed on the wild animals.  相似文献   
1000.
The overall influence of urbanization on how flows of different frequency might change over time, while important in hydrologic design, remains imprecisely known. In this study, we investigate the effects of urbanization on flow duration curves (FDCs) and flow variability through a case study of eight watersheds that underwent different amounts of growth, in the Puget Sound region in Western Washington State, United States. We computed annual FDCs from flow records spanning 1960‐2010 and, after accounting for the effects of precipitation, we conducted statistical trend analyses on flow metrics to quantify how key FDC percentiles changed with time in response to urbanization. In the urban watersheds, the entire FDC tended to increase in magnitude of flow, especially the 95th‐99th percentile of the daily mean flow series, which increased by an average of 43%. Stream flashiness in urban watersheds was found to increase by an average of 70%. The increases in FDC magnitude and flashiness in urbanizing watersheds are most likely a result of increasing watershed imperviousness and altered hydrologic routing. Rural watersheds were found to have decreasing FDC magnitude over the same time period, which is possibly due to anthropogenic extractions of groundwater, and increasing stream flashiness, which is likely a result of reductions in base flow and increasing precipitation intensity and variability.  相似文献   
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