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421.
The purpose of this research was to verify that various segments of the rock climbing community have different attitudes toward resource management and to aid in the understanding of attitudinal differences that can affect rock-climbing management. Respondents were given an on-site questionnaire; 400 usable surveys were collected from 13 different locations in the United States. Respondents identified themselves according to the type of climbing they participated in (e.g., traditional climbing, sport climbing, and hybrid climbing). Factor analysis identified five usable factors: bolt placement/use, need for management, reservations about management, appropriateness of bolts, and climbers' self-perception. A repeated-measures analysis of variance identified significant differences among responses from traditional and sport climbers on four of the five scales used to measures attitudes. The variance among the climbing subgroups indicated that various climbing groups had significantly different attitudes toward management. All climbers surveyed had reservations about the management process. Results from the analysis indicated that climbers from all three groups (traditional, sport, and hybrid) felt that managers did not adequately understand the activity of climbing, climbers did not adequately understand the management process, climbing was not treated fairly in the management process in comparison to other activities, and climbing was micromanaged.  相似文献   
422.
1. Each NABC member institutions should ensure that subject matter on ethical issues associated with food and agricultural biotechnology is systematically integrated into the curriculum of their institution. The pattern of implementation will vary a teach institution, but we expect that some combination of the following three strategies will be employed at most institutions. a) Modules Included in Basic and Applied Science Courses b) Modules Included in General Courses on Applied Ethics c) Special courses on Ethics and Food Biotechnology 2. Each NABC member institution should develop an institutional mechanism for supporting faculty interest and research on ethical issues. Again, implementation will vary. In some institutions, an informal network of interested colleagues will fulfill this function, but in many places an annual workshop or a formal faculty/center will be needed to carry this out. 3. Each NABC institution should include information on ethical issues in its public education programs on biotechnology. Extension and public policy education materials should be developed and NABC institutions should actively disseminate materials on ethical issues beyond the campus. 4. NABC should support these efforts of member institutions by sponsoring regular workshops or conferences on ethical issues,aiding in the development of modules and teaching materials, and aiding in the dissemination of materials in both printed and electronic form. In particular, NABC should support these efforts by raising funds from member institutions, from foundations and government agencies, and from the private sector,including commercial biotechnology companies. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
423.
424.
Summary Some of the environmental and developmental activities assisted by Britain's Programme of Overseas Aid are outlined. In particular, the article draws attention to a new booklet published by the Overseas Development Administration to mark the European Year of the Environment which, in the Minister's words, shows how through British aid, programme improvements are possible by a combination of sound scientific research and a sensitivity to people's needs.Mr Christopher Patten, Member of Parliament for Bath, is the UK's current Minister for Overseas Development. He also serves as Minister of State for Foreign and Commonwealth Affairs. The Minister may be contacted through the offices of the Overseas Development Administration, Eland House, Stag Place, London SW1E 5DH, UK.  相似文献   
425.
A 4-year study (1972–1976) determined long-term trends of organochlorine residues (DDT, DDE, DDD, PCB's, mirex) and trawl-susceptible organisms in a shallow, river-dominated estuary in North Florida (Apalachicola Bay, USA). Moderate levels of such compounds were found in various species prior to the restricted use of DDT in 1972. A subsequent precipitous decline in organochlorine besidues was attributed to decreased upland usage, major flushing of the river basin in early 1973, and various factors associated with estuarine function. No mirex was found in sediments or aquatic organisms. Apparently, the half-life of organochlorines is relatively short in this bay system. Various statistical methods were used to test the relationships of different physico-chemical and biological parameters. During the 4-year study period, seasonal river flow fluctuations dominated water color, turbidity, salinity, nutrients (NO3), chlorophyll a, and the temporal succession of fishes in the bay. Certain long-term trends of fish associations were noted; relative dominance of key fish species declined and stabilized while bay-wide species richness and diversity increased with time. Qualitative changes in species representation determined the long-term pattern of community variability. This was consonant with a distinctive fish fauna during the first year of sampling. The bay anchovy Anchoa mitchilli was dominant during 9 of the first 12 monts of the project; this influenced the time-related changes in community indices. Temporally clustered fish associations reflected the importance of river flow in the estuarine environment. Direct correlation of fish distribution with the rapid disappearance of organochlorine compounds was complicated by aperiodic natural phenomena such as storms and river fluctuations. Population and community trends appeared consistent with other studies showing similar patterns of dominance of stress-resistant fish populations and related changes in community parameters. In this case, the relatively predictable annual succession of fish associations allowed an appraisal of key forcing functions. Due to the high level of seasonal and annual biological variability in this estuary, there were some problems in the application of linear statistical models to the data base. Although the long-term trend of relative species representation is useful as an index of stress, new techniques are needed to analyze extensive field data so that functions such as trophic interactions are included in the estimation of causal relationships. There are indications that such effects could be related to the impact of organochlorine compounds on estuarine systems.  相似文献   
426.
The ‘modernist’ project that has come to dominate food and agricultural policy has failed to provide sustainable outcomes for many poor people in developing countries. Conventional agricultural science is not able to explain let alone address these concerns because it is based on a static equilibrium-centred view that provides little insight into the dynamic character of agri-food systems. This paper analyses how prevailing narratives of technological change and economic growth have come to dominate key food and agriculture policy debates. It seeks to counter these orthodox notions by emphasising that agri-food systems are embedded in complex ecological, economic and social processes, and showing how their interactions are dynamic and vulnerable to short-term shocks and long-term stresses like climate change. The paper makes the case for a deeper understanding of diverse ‘rural worlds’ and their potential pathways to sustainability through agriculture. Moreover, it argues for a normative focus on poverty reduction and concern for the distributional consequences of dynamic changes in agri-food systems, rather than aggregates and averages. Finally, it sets out an interdisciplinary research agenda on agri-food systems that focuses on dynamic system interactions in complex, risk-prone environments and explores how pathways can become more resilient and robust in an era of growing risk and uncertainty.  相似文献   
427.
Fragmentation of landscapes is a pervasive source of environmental change. Although understanding the effects of fragmentation has occupied ecologists for decades, there remain important gaps in our understanding of the way that fragmentation influences mobile organisms. In particular, there is little tested theory explaining the way that fragmentation shapes interactions between consumers and resources. We propose a simple model that explains why fragmentation may harm consumers even when the total amount of resources on the landscape they use remains unchanged. In particular, we show that nonlinearity in the relationship between resource availability and benefits acquired by consumers from resources can cause a decrease in benefits to consumers when landscapes are subdivided into isolated parts and when the distribution of consumers in fragments is not matched to the distribution of resources. We tested predictions of the model using a laboratory system of cabbage looper (Trichoplusia ni) larvae on artificial landscapes. Consistent with the model's predictions, survivorship of larvae decreased when landscapes with heterogeneous resources were fragmented into isolated parts. However, average mass of surviving larvae did not change in response to fragmentation. With basic knowledge of consumer resource use patterns and landscape structure, our model, supported by our experiment, contributes new understanding of the resource-mediated effects of fragmentation on consumers.  相似文献   
428.
This study investigates the influence of genetic factors on survey response behavior. A pool of 558 male and 500 female twin pairs from the Minnesota Twin Registry (MTR) was asked to complete a paper‐and‐pencil survey of leadership activities. We used quantitative genetics techniques to estimate the genetic, shared environmental, and nonshared environmental effects on people's compliance with the request for survey participation. Results indicated that genetic influences explained 45% of the variance in survey response behavior for both women and men, with little shared environmental effects. Similar estimates were obtained after we partialled out potential confounds including twin closeness, age, and education. The results have important implications for response rates and nonresponse bias in survey‐based research. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
429.
In this study we test one central prediction from sociogenomic theory—that social and non-social taxa share common genetic toolkits that regulate reproduction in response to environmental cues. We exposed Drosophila females of rover (for R) and sitter (for s) genotypes to an ovary-suppressing pheromone derived from the honeybee Apis mellifera. Surprisingly, queen mandibular pheromone (QMP) affected several measures of fitness in flies, and in a manner comparable to the pheromone’s normal effect on bee workers. QMP-treated sitter flies had smaller ovaries that contained fewer eggs than did untreated controls. QMP-treated rover flies, by contrast, showed a more variable pattern that only sometimes resulted in ovary inhibition, while a third strain of fly that contains a sitter mutant allele in a rover background (for s2) showed no ovarian response to QMP. Taken together, our results suggest that distinctly non-social insects have some capacity to respond to social cues, but that this response varies with fly genotype. In general, the interspecific response is consistent with a conserved gene set affecting reproductive physiology. The differential response among strains in particular suggests that for is itself important for modulating the fly’s pheromonal response.  相似文献   
430.
Abstract

This paper examines controversy during the 2001 foot-and-mouth outbreak after mass carcass burial sites were selected at two sites in northeast England, and focuses on shortcomings in public consultation surrounding the carcass disposal policy. The slaughter of six million animals necessitated a national disposal strategy on a hitherto unknown scale. The belated decision to concentrate carcass disposal in a small number of mass burial sites provoked more opposition in the two ex-mining localities selected in the northeast than anywhere else. In both cases local liaison committees were established to manage dialogue between residents and public authorities. We argue that, although seen by the authorities primarily as a vehicle for risk communication and public reassurance, for residents these functioned chiefly as a vehicle for holding public authorities to account. These divergent purposes were overshadowed by the chaotic circumstances in which the early stages of the mass burial policy were implemented, and the way in which the carcass disposal policy was dictated by the operation of the slaughter policy, whose draconian form precluded any but the most cursory public consultation.  相似文献   
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