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51.
Social relations associated with conventional agricultural exports find their origins in long term associations based on business, family, and class alliances. Working outside these boundaries presents a host of challenges, especially where small producers with little economic or political power are concerned. Yet, in many developing countries, alternative trade organizations (ATOs) based on philosophies of social justice and/or environmental well-being are carving out spaces alongside traditional agricultural export sectors by establishing new channels of trade and marketing. Coffee provides a case in point, with the fair trade and certified organic movements making inroads into the market place. In their own ways, these movements represent a type of economic and social restructuring from below, drawing upon and developing linkages beyond the traditional boundaries of how coffee is produced and traded. An examination of the philosophies of the fair trade and organic coffee movements reveal that the philosophical underpinnings of both certified organic and fair-trade coffee run counter to the historical concerns of coffee production and trade. Associations of small producers involved in these coffees face stiff challenges – both internal and external to their groups. More work, especially in situ fieldwork aimed at uncovering the challenges, benefits, tensions, and successes, is needed to understand better the ways these networks operate in the dynamic agro-food complex.  相似文献   
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Craig JK  Burke BJ  Crowder LB  Rice JA 《Ecology》2006,87(9):2366-2377
The outcome of predation interactions between growing, size-structured predator and prey cohorts is difficult to predict. We manipulated the food resources available to juvenile spot subject to predation from southern flounder in a 60-day replicated pond experiment to test the hypothesis that spot growing slowly would experience higher predation mortality and stronger selection against small individuals than those growing rapidly. A nearly threefold difference in average growth rate between fast- and slow-growth treatments led to twofold higher predation mortality of slow-growing spot. Relative to no-flounder controls, larger spot were overrepresented at the end of the experiment in both treatments, but the magnitude of flounder size selection was much greater in the slow-growth treatment. The experimental results agreed qualitatively, but not quantitatively, with predictions from a prior size-dependent foraging model. In particular, the model significantly underestimated observed shifts in spot size structure to larger sizes. We hypothesized that competitive release and associated increases in spot growth due to thinning by flounder might reconcile this difference, and extended the model to incorporate this process. We then used the model to estimate the relative contribution of these two confounded predator effects (size-selective predation and thinning) to observed shifts in spot size structure. Model simulations indicated that the combined effects of size-selective predation and thinning could account for nearly all of the observed shift in spot size structure, but that thinning was the more important process. Our results highlight the utility of combining experimental and modeling approaches to unravel the complexities underlying interactions between growing, size-structured predator and prey cohorts.  相似文献   
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The first phase of noise mapping and action planning in Ireland, in accordance with EU Directive 2002/49/EC, is now complete. In total this included one agglomeration, one airport and approximately 600 km of major roads outside the agglomeration. These noise maps describe the level of noise exposure of approximately 1.25 million people. The first phase of noise mapping was dealt with by five noise mapping bodies while 26 action planning authorities were involved in the development of the associated action plans. The second phase of noise mapping, due to be completed in 2012, sees a reduction in the defined thresholds describing the required agglomerations, roads and railways that have to be mapped. This will have a significant impact on the extent of mapping required. In Ireland this will result in an increased number of local authorities being required to develop strategic noise maps for their area along with the further development of associated action plans. It is appropriate at this point to review the work process and results from the first phase of noise mapping in Ireland in order to establish areas that could be improved, throughout the noise mapping project. In this paper a review of the implementation procedures focussing on (dominant) road traffic noise is presented. It is identified that more standardisation is needed and this could be achieved by the establishment of a national expert steering group.  相似文献   
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The intentional dissemination of Bacillus anthracis (anthrax) spores at multiple locations in the United States in the fall of 2001 resulted not only in several deaths and illnesses (including psychological effects), but likely changed lifestyles and attitudes, and increased the public's awareness of individual vulnerability. While federal resources had previously been committed to preparing local public health agencies for counter‐terrorism activities and to enhance environmental and medical response, these release episodes have increased the consistency of environmental and medical response activities, and increased government resources for homeland security. This article abstracts current information from many sources that summarize the environmental responses to the anthrax releases. The article discusses the international agreements and the U.S. regulations concerning biological weapons, the characteristics of the anthrax organism, potential exposure pathways, adverse health conditions resulting from inhalation exposure, the environmental response to two specific release episodes, environmental sampling and analytical procedures, recommended personal protective equipment, and the subsequent federal efforts to improve response capabilities. © 2003 Wiley Periodicals, Inc.  相似文献   
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A review of past research revealed inconsistent findings concerning the relationship between job involvement and work-family conflict. This study tested whether family involvement moderates the relationship between job involvement and work-family conflict. Two types of family involvement (spouse and parent) and two types of work-family conflict (job-spouse and job-parent) were assessed. Data were gathered via questionnaire from a sample of nonteaching professionals employed by a large public university in the northeastern United States. As hypothesized, job involvement and job-spouse conflict were positively related for individuals high in spouse involvement and unrelated for individuals low in spouse involvement. Contrary to prediction, parental involvement did not moderate the relationship between job involvement and job-parent conflict. Instead, job involvement was positively related to job-parent conflict regardless of the level of parental involvement. Results are discussed in terms of standards for role performance and strength of role demands. Implications for future research are also discussed.  相似文献   
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The intraspecific patterns of morphometric variation were examined in Fucus distichus L. and F. evanescens C.Ag., using samples gathered from 49 sites spread across the North Atlantic. Ten characters were measured on each plant. The data were subjected to bivariate regression analyses, canonical correlation analysis and nested analysis of variance (ANOVA). It was shown that the combined effects of the three environmental variables measured for each site (latitude, longitude and exposure) could only explain 23 and 15% respectively of the intraspecific morphometric variation. Inter-individual, within-site differences accounted for a further 62 and 53%. The remaining variation appears to be expressed on a geographic scale of tens of kilometres at most. Thus, the species seem to take the form of fine-scale phenotypic mosaics, superimposed on weak major clines. Such a pattern has not previously been described for any macroalga, although it is known in some angiosperms.  相似文献   
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