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191.
To provide information necessary for a license application for a deep repository for spent nuclear fuel, the Swedish Nuclear Fuel and Waste Management Co is carrying out site investigations, including extensive studies of different parts of the surface ecosystems, at two sites in Sweden. Here we use the output from detailed modeling of the carbon dynamics in the terrestrial, limnic and marine ecosystems to describe and compare major pools and fluxes of organic matter in the Simpevarp area, situated on the southeast coast of Sweden. In this study, organic carbon is used as a proxy for radionuclides incorporated into organic matter. The results show that the largest incorporation of carbon into living tissue occurs in terrestrial catchments. Carbon is accumulated in soil or sediments in all ecosystems, but the carbon pool reaches the highest values in shallow near-land marine basins. The marine basins, especially the outer basins, are dominated by large horizontal water fluxes that transport carbon and any associated contaminants into the Baltic Sea. The results suggest that the near-land shallow marine basins have to be regarded as focal points for accumulation of radionuclides in the Simpevarp area, as they receive a comparatively large amount of carbon as discharge from terrestrial catchments, having a high NPP and a high detrital accumulation in sediments. These focal points may constitute a potential risk for exposure to humans in a future landscape as, due to post-glacial land uplift, previous accumulation bottoms are likely to be used for future agricultural purposes.  相似文献   
192.
O'Brien K  Eriksen S  Sygna L  Naess LO 《Ambio》2006,35(2):50-56
Most European assessments of climate change impacts have been carried out on sectors and ecosystems, providing a narrow understanding of what climate change really means for society. Furthermore, the main focus has been on technological adaptations, with less attention paid to the process of climate change adaptation. In this article, we present and analyze findings from recent studies on climate change impacts, vulnerability, and adaptation in Norway, with the aim of identifying the wider social impacts of climate change. Three main lessons can be drawn. First, the potential thresholds and indirect effects may be more important than the direct, sectoral effects. Second, highly sensitive sectors, regions, and communities combine with differential social vulnerability to create both winners and losers. Third, high national levels of adaptive capacity mask the barriers and constraints to adaptation, particularly among those who are most vulnerable to climate change. Based on these results, we question complacency in Norway and other European countries regarding climate change impacts and adaptation. We argue that greater attention needs to be placed on the social context of climate change impacts and on the processes shaping vulnerability and adaptation.  相似文献   
193.
Recent studies from a number of countries have shown that measurable concentrations of both human and veterinary pharmaceuticals can be found in a variety of environmental matrices such as surface and ground water, soils, and sediments. Few data are available that characterize the sources, exposure and effects of pharmaceuticals in the environment and there is clearly a need to define these parameters within a Canadian context. We present in this paper the first report in southern Ontario, Canada on the geographic and temporal distribution of pharmaceuticals detected within seven tributaries receiving primarily agricultural inputs in a typical watershed. Of the 28 pharmaceuticals surveyed, 14 were detected in the streams sampled (n=125). Temporal trends in concentration for five frequently detected pharmaceuticals show pulses occurring between May and November of 2003 at similar but varying times over the seasons, depending on the pharmaceuticals, flow rate, and precipitation. Fluctuations in concentration of ions indicative of agricultural run off, such as nitrate and phosphate, were not found to be useful predictors of changes in pharmaceutical concentration (P>0.4), however a significant correlation between dissolved organic carbon and monensin and carbamazepine concentrations were observed (P<0.013). Exposure profiles illustrating concentration distributions for three of the more prevalent pharmaceuticals detected, including lincomycin, monensin and carbamazepine, showed a log normal distribution, useful for calculating centiles of environmental concentrations. While distributions of estimated total potency of pharmaceuticals detected in the surface waters suggested small risks of environmental effects of mixtures to daphnia, green algae, Lemna gibba, and fish, the significance of non-target effects and impacts due to chronic low level exposures to chemical mixtures remains unclear.  相似文献   
194.
Much attention is drawn to polycyclic aromatic hydrocarbons(PAHs) as an air pollutant due to their toxic, mutagenic and carcinogenic properties. Therefore, to understand the levels, seasonality, sources and potential health risk of PAHs in two distinct geographical locations at Karachi and Mardan in Pakistan, total suspended particle(TSP) samples were collected for over one year period. The average total PAH concentrations were 31.5 ± 24.4 and 199 ± 229 ng/m3 in Karachi and Mardan, re...  相似文献   
195.
196.
志愿非法规性举措(VNRI)在加拿大的使用,加之审慎混用各种手段,包括法规框架与经济手段,已经带来公司文化和行为的显著变化.随着各家公司和代表其利益的协会鼓励环境领导,负责任企业家便成为一种现实.详细考察了两个计划:加速削减/消除毒物(ARET)和全国包装议定书(NaPP).虽然这两个计划在其目的、目标和对象上有显著差异,而且它们所解决的环境问题也不同,但两者都成功地加以实施,达到了以低于法规所设想的费用达到最高环境质量水平之目的,并产生了更大的和未预见到的效益.  相似文献   
197.
In this paper we argue that organizational identification is predictive of employee interests and concerns during periods of organizational change. More specifically, we assert that organizational identification may largely determine whether employees may be focused upon the change related outcomes (e.g., salary, expenses, etc.), or on the change processes (e.g., procedures, voice and participation options, etc.). Data of both a scenario experiment and a survey are presented indicating that high and low identifiers indeed are differentially interested in process and outcome information. The results suggest that people who identify less with the organization are more likely to be focused upon the change outcomes then on the change process, while people who identify highly (i.e., deep structure) with the organization are more likely to be focused upon the change processes then on the change outcomes. The benefits of awareness of organizational members' level of identification for organizational change management are discussed. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
198.

Introduction

Older drivers are increasing in number and they often have health conditions that place them at high risk for motor-vehicle crashes (MVC). Screening is underutilized, and is rarely done in hospital settings.

Methods

A convenience sample of 755 older adults completed age related driving disorders screening at University of California, San Diego inpatient and outpatient health centers. Screening included three strength/frailty tests, two vision tests (acuity and fields), and two cognitive tests, based on AMA recommendations. The average age of participants was 72.5; 55.5% were male and 94% English-speaking; 17.8% of older adults failed at least one aspect of screening.

Results

In multivariate analysis, significant associations of failed status were age, male sex, selfrestrictions of driving, and inpatient screening locations. The screening identified one in six adults to be 'high-risk' for age related driving disorders. Screening was effective and feasible in both inpatient and outpatient settings.

Impact on industry

As the driving population ages, industry, government and health car providers need to plan for the management of driving impairments in older adults.  相似文献   
199.
Prokopy, Linda Stalker, Z. Asligül Göçmen, Jing Gao, Shorna Broussard Allred, Joseph E. Bonnell, Kenneth Genskow, Alicia Molloy, and Rebecca Power, 2011. Incorporating Social Context Variables Into Paired Watershed Designs to Test Nonpoint Source Program Effectiveness. Journal of the American Water Resources Association (JAWRA) 47(1):196‐202. DOI: 10.1111/j.1752‐1688.2010.00508.x Abstract: In a traditional paired watershed study, watersheds are selected to be as similar as possible so that conclusions may be drawn about the performance of Best Management Practices. We have extended the paired watershed concept to examine the effectiveness of watershed management programs by adding comparative criteria for social characteristics. For four different 8 or 11/12 digit hydrologic unit code (HUC) watersheds in the Midwest, we have piloted a systematic method for selecting paired subwatersheds. First, we developed a list of 11 key variables. Next, a factor analysis was conducted to determine the underlying structure of the 11 input variables. Finally, in each of the four watersheds, potential paired subwatersheds (all 14 digit HUCs) were selected using the factors in a cluster analysis. Informal interviews were then held with key informants in each watershed to provide qualitative assessments of criteria that could impact the comparability of the subwatersheds. This method for selecting paired watersheds should be helpful for other researchers to test the effectiveness of watershed management programs focused on behavior change.  相似文献   
200.
Soil microbes drive the classic plant diversity-productivity pattern   总被引:1,自引:0,他引:1  
Ecosystem productivity commonly increases asymptotically with plant species diversity, and determining the mechanisms responsible for this well-known pattern is essential to predict potential changes in ecosystem productivity with ongoing species loss. Previous studies attributed the asymptotic diversity-productivity pattern to plant competition and differential resource use (e.g., niche complementarity). Using an analytical model and a series of experiments, we demonstrate theoretically and empirically that host-specific soil microbes can be major determinants of the diversity-productivity relationship in grasslands. In the presence of soil microbes, plant disease decreased with increasing diversity, and productivity increased nearly 500%, primarily because of the strong effect of density-dependent disease on productivity at low diversity. Correspondingly, disease was higher in plants grown in conspecific-trained soils than heterospecific-trained soils (demonstrating host-specificity), and productivity increased and host-specific disease decreased with increasing community diversity, suggesting that disease was the primary cause of reduced productivity in species-poor treatments. In sterilized, microbe-free soils, the increase in productivity with increasing plant species number was markedly lower than the increase measured in the presence of soil microbes, suggesting that niche complementarity was a weaker determinant of the diversity-productivity relationship. Our results demonstrate that soil microbes play an integral role as determinants of the diversity-productivity relationship.  相似文献   
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