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51.
The aim of this paper is to understand how local residents participate in the construction of local environmental problems and to evaluate a particular analytical approach in environmental sociology to study this phenomenon. The paper is based on an interview study with a sample of local residents. The analysis demonstrates how the local residents attempt to construct a local environmental problem. In particular, the study focuses on how involved actors are positioned, how different sorts of knowledge claims are used, and how the neglect the residents perceive from the authorities affects the attempt to construct a local environmental problem. The study shows that the local residents play a central role in the construction of the situation and that the evaluated model could be very helpful as an analytical tool in the investigation of local residents' participation in the construction of environmental problems.  相似文献   
52.
This paper examines how local communities adapt to climate change and how governance structures can foster or undermine adaptive capacity. Climate change policies, in general, and disaster risk management in mountain regions, in particular, are characterised by their multi-level and multi-sectoral nature during formulation and implementation. The involvement of numerous state and non-state actors at local to national levels produces a variety of networks of interaction and communication. The paper argues that the structure of these relational patterns is critical for understanding adaptive capacity. It thus proposes an expanded concept of adaptive capacity that incorporates (horizontal and vertical) actor integration and communication flow between these actors. The paper further advocates the use of formal social network analysis to assess these relational patterns. Preliminary results from research on adaptation to climate change in a Swiss mountain region vulnerable to floods and other natural hazards illustrate the conceptual and empirical significance of the main arguments.  相似文献   
53.
Conservation translocation is a common method for species recovery, for which one increasingly frequent objective is restoring lost ecological functions to promote ecosystem recovery. However, few conservation translocation programs explicitly state or monitor function as an objective, limiting the ability to test assumptions, learn from past efforts, and improve management. We evaluated whether translocations of hihi (Notiomystis cincta), a threatened New Zealand passerine, achieved their implicit objective of restoring lost pollination function. Through a pollinator-exclusion experiment, we quantified, with log response ratios (lnR), the effects of birds on fruit set and seed quality in hangehange (Geniostoma ligustrifolium), a native flowering shrub. We isolated the contributions of hihi by making comparisons across sites with and without hihi. Birds improved fruit set more at sites without hihi (lnR = 1.27) than sites with hihi (lnR = 0.50), suggesting other avian pollinators compensated for and even exceeded hihi contributions to fruit set. Although birds improved seed germination only at hihi sites (lnR = 0.22–0.41), plants at sites without hihi had germination rates similar to hihi sites because they produced 26% more filled seeds, regardless of pollination condition. Therefore, although our results showed hihi improved seed quality, they also highlighted the complexity of ecological functions. When an important species is lost, ecosystems may be able to achieve similar function through different means. Our results underscore the importance of stating and monitoring the ecological benefits of conservation translocations when functional restoration is a motivation to ensure these programs are achieving their objectives.  相似文献   
54.
Polychlorinated naphthalenes (PCNs) and non-ortho chlorinated biphenyls (non-ortho CBs) were analysed in blubber, nuchal fat, liver, muscle, kidney and brain of three male harbour porpoises (Phocoena phocoena) from the west coast of Sweden. To estimate spatial variation, PCNs and non-ortho CBs were analysed in six blubber samples collected at different anatomical sites of each animal. Highest wet weight concentrations of ΣPCNs were detected in the lipid rich tissues (blubber and nuchal fat) and liver (520–730 and 520 pg/g, respectively) and lowest in brain (22 pg/g). TetraCNs were most abundant in muscle, kidney and brain, while the hexaCNs were most abundant in the lipid rich tissues and liver. The highest lipid weight concentration recorded (11 ng/g) was for the hexaCN congeners no. 66/67 in liver. These coeluting hexaCN congeners accounted for 80–100% of total hexaCNs in all tissues examined.Concentrations of Σnon-ortho CBs were highest in lipid rich tissues (220–280 pg/g wet weight). Non-ortho CB no. 77 and 169 constituted between 62–86% and 4.9–9.3%, respectively, of total Σnon-ortho CBs. No major variation of Σnon-ortho CB concentrations was found between the six different blubber sites but higher ΣPCN concentrations (wet weight) were found dorsally at the peduncle. Toxic equivalent concentrations (TEQs) showed that non-ortho CB no. 126 was the main contributor to total TEQs in all tissues, except liver in which hexaCN congener nos. 66/67 contributed to about 50% of total TEQs.  相似文献   
55.
Little is known about how cryptic colouration influences prey search in near-surface aquatic habitats, although such knowledge is critical for understanding the adaptive value of colour crypsis as well as the perceptive constraints influencing foraging behaviour in these environments. This study had two main aims: (1) to investigate how background colour matching by prey affects foraging efficiency by brown trout parr and (2) to investigate how foraging ability on cryptic and conspicuous prey is affected by fish size at age (reflecting dominance). We addressed these questions by training wild brown trout parr to forage individually on live brown-coloured maggots on a cryptic (brown) or conspicuous (green) background. A separate experiment confirmed the absence of trout preference for brown or green substrate. The results show that prey background colour matching increases search time in brown trout. Search time generally decreased by learning, but conspicuous prey remained an easier prey to find throughout the six training trials. Thus, perceptive constraints appear to limit search efficiency for cryptic prey, suggesting that cryptic colouration can confer survival benefits to prey in natural environments. Smaller fish generally found conspicuous prey faster than larger individuals, whereas search time for cryptic prey was not influenced by body size. This suggests that smaller individuals compensate for inferior competitive ability by increasing foraging activity rather than improving cognitive ability. The technique of varying cognitive demands in behavioural tasks could be used more in future studies aimed at distinguishing motivational effects from cognitive explanations for variation in behavioural performance.  相似文献   
56.
Fugitive emissions account for approximately 50% of total hydrocarbon emissions from process plants. Federal and state regulations aiming at controlling these emissions require refineries and petrochemical plants in the United States to implement a Leak Detection and Repair Program (LDAR). The current regulatory work practice, U.S. Environment Protection Agency Method 21, requires designated components to be monitored individually at regular intervals. The annual costs of these LDAR programs in a typical refinery can exceed US$1,000,000. Previous studies have shown that a majority of controllable fugitive emissions come from a very small fraction of components. The Smart LDAR program aims to find cost-effective methods to monitor and reduce emissions from these large leakers. Optical gas imaging has been identified as one such technology that can help achieve this objective. This paper discusses a refinery evaluation of an instrument based on backscatter absorption gas imaging technology. This portable camera allows an operator to scan components more quickly and image gas leaks in real time. During the evaluation, the instrument was able to identify leaking components that were the source of 97% of the total mass emissions from leaks detected. More than 27,000 components were monitored. This was achieved in far less time than it would have taken using Method 21. In addition, the instrument was able to find leaks from components that are not required to be monitored by the current LDAR regulations. The technology principles and the parameters that affect instrument performance are also discussed in the paper.  相似文献   
57.
Pictures of sides of beef, hanging from overhead rails in refrigerated warehouses and meat-processing plants, often leave a feeling of unease. These pictures provoke the notion that human beings have no right to inflict suffering and death on other sentient beings for the sole purpose of providing food. However, the ethical analysis conducted in this study shows that meat production, if animal welfare and deaths per calorie created are considered, is less of a pressing problem compared to the production of milk. While meat can be provided with minimal suffering to animals, the consumption of milk is always associated with considerable suffering during the dairy cow’s life-span and the lives of their offspring. Moreover, more bovine deaths per unit of calorific value created are associated with milk production compared to meat production. The vegan movement, which is currently growing, wishes to minimise farm animal suffering as much as possible. However, if a vegan diet is not possible, consumers should make an informed decision about the products they consume. Replacement of the calories obtained from meat with those from milk and dairy products is not rational if animal welfare is considered.  相似文献   
58.
Environmental fungi become a potential Indoor Air Quality (IAQ) problem when adequate moisture and nutrients are present in building materials. Because of their potential to rapidly spread contamination throughout a building, ventilation system materials are of particular significance as potential microbial contamination sources. Current recommendations are to discard fibrous glass insulation that appears to be wet or moldy. Unfortunately, this advice is not always followed. Instead, cleaning is sometimes being used in buildings to remediate fibrous glass duct liner that is already contaminated with microbial growth. The objectives of this research program were to: 1) determine, under dynamic test conditions, whether fungal spore levels on heating, ventilating, and air-conditioning (HVAC) duct material surfaces could be substantially reduced by thorough vacuum cleaning, 2) evaluate whether subsequent fungal growth could be limited or contained by mechanical cleaning, and 3) provide data concerning the advisability of cleaning duct materials. The constant high relative humidity (RH) environment to which the test materials were exposed during this study was selected as a favorable growth environment that is frequently found in Southeastern United States HVAC systems. The results showed that, following cleaning, the levels of the two test fungi, A. versicolor and P. chrysogenum, recovered to preclean levels within 6 weeks. Therefore, mechanical cleaning by contact vacuuming alone was able to only temporarily reduce the surface fungal load. The current guidelines to discard contaminated materials should be followed.  相似文献   
59.
在解决复杂的土地管理问题时,对短缺或者有争执的资源进行地理评估有助于不同利益相关者之间沟通认识和增进理解.本文中,我们说明如何使用遥感和GIS收集和汇总瑞典北部驯鹿放牧者和其他土地使用者(林业、采矿业、旅游业等等)的土地使用活动及使用模式的信息.该项目主要基于最终的土地使用者,即驯鹿放牧者们所做的工作,体现了面向土地使用者的新的努力.发展驯鹿业的土地利用规划的基础有以下几个方面:收集并数字化传统的驯鹿栖息地生态学和景观信息将这些信息与来自野外调查及基于人造卫星观测的植被分类结果整合;绘制其他土地使用者的活动情况图.最终的土地利用规划提供的信息有利于驯鹿放牧者与其他利益相关者之间的磋商,并有助于驯鹿管理实施.该项目可作为一种大众参与和计划编制的模式,从而使本土信息和先进的遥感技术融入一个交互式的过程中.  相似文献   
60.
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