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151.
152.
Anti-HEV antibodies were detected in animals from abattoir and in farms from northeast Brazil. Our results suggest that HEV is highly disseminated in the swine population and might present a great risk to animal handlers and for consumption of raw or undercooked meat and meat products in northeast Brazil.  相似文献   
153.
The Urban Cleaning Company of the City of Rio de Janeiro - COMLURB launched the Recycling Separation Center Project (Projeto Central de Separação de Recicláveis or CSR) in 2003. The objectives of the project were the adequate disposal of solid urban waste as well as the generation of employment and income. The COMLURB Project had economic, environmental and social facets, and the researchers sought to establish whether COMLURB had prepared reports that would enable evaluation of the investment made and the results obtained. In particular, the researchers sought to establish whether COMLURB financial statements set out the results of actions inherent to the CSR. We concluded from our analysis of the Project that the three elements of sustainability (social, environmental and economic), despite being fully present, were not adequately demonstrated. This study therefore proposes a model report with a view to enabling various information users to evaluate the results of the CSR Project.  相似文献   
154.
Public participation within environmental monitoring may contribute to increasing the knowledge on the state of the environment at the same time it promotes citizens' involvement in environmental protection. However, the use of voluntary collected data is limited due to a lack of confidence in data collection procedures. Additionally, data quality is often unknown and the data are usually dispersed and non-structured. Information and communication technologies (ICT) may promote the use of voluntary collected data through the development of a collaborative system that incorporates tools and methodologies to facilitate data collection, access and validation. Furthermore, the use of ICT may promote public involvement within environmental monitoring, since it facilitates communication among all the stakeholders. This paper analyses the role of ICT in developing a system for environmental collaborative monitoring intending to promote the use of volunteer collected data. It starts by analysing the role of volunteers within environmental monitoring and continues analysing the potential of ICT to take advantage of the benefits of using data collected by citizens. A collaborative system that allows the public to express its knowledge on the state of the environment is described. Special emphasis is given to tools that explore non-traditional types of environmental data such as images, sounds and videos in association with spatial information. To illustrate the above mentioned concepts, a case study for beach quality monitoring developed within the Senses@Watch project, is described.  相似文献   
155.
The present work presents the results of 137Cs concentration in seawater, fish and sediments samples collect in 11 sampling points, crossing the Brazilian Southeastern coastal region, from Vitória (ES) to Santos (SP), on a routine basis from 1997 to 2002. This monitoring program was carried out by the Instituto de Radioproteção e Dosimetria (IRD/CNEN/MCT), in cooperation with the Instituto de Estudos do Mar Almirante Paulo Moreira (IEAPM/Brazilian Navy), aiming at determining artificial radionuclides in marine samples. Additionally to the 137Cs results, 90Sr concentrations in fish samples from 1998 to 2002 are also reported.The 137Cs in seawater follows a lognormal distribution, with a geometric mean of 1.8 Bq m-3 and a geometric standard deviation of 1.4 (n=54), decay corrected to June/2002. For 137Cs levels in fish samples a geometric mean of 0.19 Bq kg−1 and a geometric standard deviation of 2.9 (n=39), decay corrected to June/2002, with a range of 0.03 to 1.7 Bq kg−1, were obtained. Based on the 137Cs mean concentration in fish as well as in seawater, a transfer factor of 1 × 102 was calculated, which is quite in agreement with the recommended value found in the Safety Report Serie 19.  相似文献   
156.
The aim of this study was to evaluate the water quality of the Cértima River basin (Central Portugal). For that purpose, surface water samples were collected in March, May and July 2003, at 10 selected sampling sites, and were analysed for physicochemical parameters, namely temperature, conductivity, pH, total suspended solids, dissolved oxygen, biochemical oxygen demand (BOD5), Kjeldahl nitrogen and total phosphorus. Results revealed an acceptable water quality during the spring season. Maxima of 64 mg dm−3 for BOD5, 39 mg dm−3 for Kjeldahl nitrogen, and 5.2 mg dm−3 for total phosphorus, were recorded during summer, indicating a significant degradation of the water quality in a river stretch located downstream of the town of Mealhada. These values, which did not comply with the objectives of minimum quality for surface waters prescribed by the Portuguese legislation, were related to domestic wastewater discharges and runoff waters from a cattle farm. Besides their effects on the middle stretch of the river, these pollution sources were the most likely cause of the high nutrient load in downstream waters, and thus may have a major impact on the trophic status of Pateira de Fermentelos, a sensitive wetland area located in the lower Cértima basin.  相似文献   
157.
Methods to determine nutrient release rates of coated fertilizers usually rely on chemical analyses, which often are time-consuming and/or expensive. Our goal was to develop an innovative and rapid low-cost method to evaluate nutrient release from polymer coated MAP or urea using conductometry. The release in water is determined by measuring the electric conductivity (EC) over time, with intervals dependent on release rates. In the case of soluble salt fertilizers, EC can be immediately determined and converted to a concentration using a calibration curve. In the case of urea, an additional step is needed to convert the neutral urea into ammonium. The release rates in water were assessed for a range of commercial and laboratory-coated fertilizers. A validation test demonstrated strong agreement with the release determined using analytical techniques. The EC method hence offers an easy way to quickly evaluate the time course of release of nutrients from controlled-release fertilizers.  相似文献   
158.
The mullet fishery system encompasses a complex arrange of ecological and socioeconomic factors interacting in multiple scales on the Southern-Southeastern Brazilian coast. Similarly, to other fisheries in developing countries, overfishing and poor governance have been threatening the resilience of the mullet fishery. In this paper, we explore aspects related to fisheries management from the perspective of the concept of resilience. The industrial and artisanal fishery sectors represent the different stakeholders. The main issues of concern are related to failures in the fisheries management to properly address equity in resource access and resource use sustainability among stakeholders. Asymmetry in technology and political and economic power affect food security and income generation especially for subsistence and small-scale fishing. Despite changes in rules-in-use, overfishing and conflicts between resource users are still relevant. Fishery dynamics and resource availability are greatly affected locally by forces such as pollution, urbanization, non-selective fishing, and regionally, by the El Niño Southern Oscillation (ENSO), and industrial (purse-seine) fishery. Considering the influence of ENSO on this fishery, a time span of at least 7 years to investigate this system could provide better answers to improve the management. Effective resilient fisheries should rely on three aspects. First, there should be a flexible fish allocation system based on ecosystem variability. Secondly, fish allocation should prioritize food security and poverty alleviation. Thirdly, a monitoring system should be implemented that takes into consideration ecosystem, fisheries and human dimensions to support a flexible and adaptive fisheries management, with resilient fisheries as an ultimate goal.  相似文献   
159.
Environmental Science and Pollution Research - In the current study, water quality of five river sites in Parana River basin (Brazil), utilized for public water supply, was assessed through a set...  相似文献   
160.
Environment, Development and Sustainability - Although sustainability assessment is widely discussed at Brazil, in Brazilian Amazon its use is still little applied, considering this territory is...  相似文献   
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