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191.
In this study, we investigated whether ammonia emissions from industrial composting of organic waste may influence the surrounding environment, using lichens as bioindicators. To this purpose, samples of N-tolerant and N-sensitive lichens, namely Xanthoria parietina and Evernia prunastri, were transplanted for 1–3 months along transects at increasing distance (0–400 m) from a composting facility in Tuscany, Italy. Atmospheric concentrations of ammonia were measured using passive samplers. The physiological response of lichen transplants was investigated by means of the photosynthetic efficiency (measured as chlorophyll a fluorescence emission), the integrity of cell membranes (measured as electrolyte leakage), and sample viability (measured as enzymatic activity of dehydrogenase). Epiphytic lichen communities were investigated using biodiversity indices. The results showed decreasing concentrations of ammonia, from 48.7 μg/m3 at the composting facility to 2.7 μg/m3 at 400 m. The N-tolerant X. parietina was not affected and some physiological parameters even showed a higher performance, while the N-sensitive E. prunastri showed a reduced performance with increasing atmospheric concentrations approaching the source. A shift from lichen communities composed by meso-acidophilous species (actual condition) to more nitrophilous communities in the near future, approaching the composting facility is suggested. It is concluded that lichens can provide useful data for decision-makers to establish correct science-based environmentally sustainable waste management policies.  相似文献   
192.
The presence of pesticide residues in fresh vegetables and fruit have been qualitatively and quantitatively determined at the laboratories of the Regional Agency for Environmental Protection (ARPA), Division of the Province of Bologna. More than 1,700 samples have been tested by routine analyses. The possible risks for consumers have been evaluated by various parameters. The most important ones were: the amount of each residue; the respective ADI (Acceptable Daily Intake) limit; the contemporary presence of different residues; an estimation of the daily intake, based on the amount of fruit and vegetables consumed per person. It has been possible to evaluate that the daily intake of pesticide residues in the province of Bologna during the period 2003–06 resulted lower than the ADI limits concerning the vegetables. According to the information on fruit consumption the daily intake of omethoate (O,O-dimethyl S-methylcarbamoylmethyl phosphorothioate) resulted higher than its ADI limit, of dicofol (2,2,2-trichloro-1,1-bis(trichloromethyl)benzenemethanol) very close to the admitted limit, under the respective limits for all the other residues.  相似文献   
193.
This study investigated the influence of angular exposure and distance from vehicular traffic on the diversity of epiphytic lichens and the bioaccumulation of traffic-related elements in a town of central Italy. An Index of Lichen Diversity (ILD) was calculated on the street-facing and the opposite side of road-lining trees and in a urban park 250 m away, and the content of selected trace elements (Al, Ba, Ce, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Sb, V, and Zn) was determined in samples of the lichen Punctelia borreri (Sm.) Krog growing on tree bark, both on the exposed and opposite sides. ILD increases with distance from traffic emissions. However, at the site with vehicle traffic, non-nitrophilous lichens decreased while nitrophilous ones increased. The concentration of the traffic-related elements Ba, Cr, Cu, Mn, Sb, and Zn accumulated in thalli of P. borreri was higher on roadside trees than in trees from the urban park. ILD was not affected by the angular exposure to the road and the bioaccumulation of traffic-related elements was similar in lichens from the side of the bole exposed to traffic emissions and particulate resuspension and from the opposite side. The angular exposure in respect to the traffic source does not influence trace element accumulation. These results are important when using lichens for biomonitoring purposes, both for planning future studies and for the reliability of the interpretation of past surveys that do not report information about the angular exposure of the collected lichen material.  相似文献   
194.
The first step in planning the actions for climate change adaptation involves performing Climate Change Vulnerability Assessment (CCVA) to vulnerable populations and ecological systems. The study aims to perform a bibliometric analysis on the CCVA research field to identify how it was structured in terms of the mostly occurring research terms and their citation impact. A set of scientific papers related to CCVA (n?=?8941) were retrieved via Elsevier’s Scopus database over the period 1996–2016 using specific keywords. The search was carried out in February 2017. The number of yearly papers published in CCVA research field increased after 2006, increasing more than six times in 2016. Our co-occurrences term analysis grouped four clusters related to (i) exposure, sensitivity, and quantitative methods for assessing CCVA, (ii) adaptive capacity and qualitative approaches, (iii) CCVA integrated approaches by combining participatory methods to quantitative ones, and (iv) collaboration and participation issues related to global change. The co-citation analysis showed that highly cited research terms were related to adaptation, exposure factors, and related changes and global change. This bibliometric analysis has provided an overall picture on the CCVA research field, particularly highlighting its utility for climate change adaptation.  相似文献   
195.
Increased awareness of the importance of environmental protection and the introduction of international standards like ISO 14001 stimulated development of environmental sustainability indicators as a means to measure systems environmental performance. Here, a thermodynamic approach, emergy analysis (Odum, 1988) was used to obtain sustainability indicators able to analyse and quantify the productive and ecological performance of four famous Italian wine productions: Chianti, Brunello di Montalcino, Nobile di Montepulciano, and Barbera d'hti. The application to agricultural production was motivated by the growing need for productive and environmentally sound development in modern agriculture, in which the resource base, the environment, is preserved. The choice of wines, more precisely, grape production, is due to their importance for Italian agriculture and the economy. All the wines demonstrated a good long-term environmental sustainability, especially in view of their high quality and in comparison with the average Italian wine production. Emergy analysis proved a powerful tool for assessing environmental performance of these systems, and its use could easily be extended to other wine productions to obtain a form of environmental performance classification of this product. Systematic use of emergy analysis to assess environmental performance of different processes and products, not necessarily in agriculture, could be useful for environmental certification.  相似文献   
196.
197.
The process used to obtain recycled Al alloys depends on the scrap quality. Rotary furnaces are normally used in Europe as they allow a great productivity and they can process low quality scrap using a salt flux to protect the molten metal from oxidation. In this article, the effect of the quantity of salt on the metal recovery has been experimentally investigated by melting several types of scrap under a mixture of NaCl–KCl–Na3AlF6 salts. The quantity of salt has been related to the salt factor (SF), which is the ratio between the non-metallic content in the scrap and the quantity of salt required. The same levels of salt factor have been tested by melting the scrap in rotary and crucible furnaces. The metal recovery increases with the salt content for both furnaces. The results obtained with the different melting processes are comparable because the yield difference is similar considering different salt factors. Crucible furnace gives greater metal recovery but it cannot replace rotary furnace in Al refining industry due to lower melting capacity. However, the results highlight that the optimisation of the Al refining process can be supported by preliminary tests through crucible furnaces reducing the time and material consumptions.  相似文献   
198.
The Nile delta sedimentation constitutes a continuous high-resolution record of Ethiopian African monsoon (EAM) regime intensity. Multi-proxy analyses performed on hemipelagic sediments deposited on the Nile deep-sea fan allow the quantification of the Saharan aeolian dust and the Blue/White Nile River suspended matter frequency fluctuations during the last 21,000 years. The radiogenic strontium and neodymium isotopes, clay mineralogy, elemental composition and preliminary palynological analyses reveal large changes in source components, oscillating between a dominant aeolian Saharan contribution during the Last Glacial Maximum (LGM) and the late Holocene (~4,000–2,000 years), a dominant Blue/Atbara Nile River contribution during the early Holocene (15,000–8,000 years) and a probable White Nile River contribution during the middle Holocene (8,000–4,000 years). The following main features are highlighted: (1) The rapid shift from the LGM arid conditions to the African Humid Period (AHP) started at about 15,000 years. The AHP extends until 8,000 years, and we suggest that the EAM maximum between 15,000 and 8,000 years is responsible for a larger Blue/Atbara Nile sediment load and freshwater input into the eastern Mediterranean Sea. (2) The transition between the AHP and the arid late Holocene is gradual and occurs in two main phases between 8,400–6,500 years and 6,500–3,200 years. We suggest that the main rain belt shifted southward from 8,000 to ~4,000 years and was responsible for progressively reduced sediment load and freshwater input into the eastern Mediterranean Sea. (3) The aridification along the Nile catchments occurred from ~4,000 to 2,000 years. This dry period, which culminates at 3,200 year, seems to coincide with a re-establishment of increased oceanic primary productivity in the western Mediterranean Sea. Such a pattern imposes a large and rapid northward shift of the rain belt over the Ethiopian highlands (5–15°N) since 15,000 years. Precipitation over Ethiopia increased from 15,000 to 8,000 years. It was followed by a gradual southward shift of the rain belt over the equator from 8,000 to 4,000 years and finally a large shift of the rain belt south the equator between 4,000 and 2,000 years inducing North African aridification. We postulate that the decrease in thermohaline water Mediterranean circulation could be part of a response to huge volumes of freshwater delivered principally by the Nile River from 15,000 to 8,000 years in the eastern Mediterranean.  相似文献   
199.
This paper aims to assess the suitability of remote sensing for enhancing the management of water body resources and for providing an inexpensive way to gather, on a wide area, weed infestation extent and optical parameter linked to the water body status. Remotely sensed satellite images and ancillary ground true data were used to produce land cover maps, trough classification techniques, and water compounds maps, applying radiative transfer models. The study proposed within the framework of the cooperation between Italian Foreign Affair Ministry (through the University of Rome) and Kenyan Authorities has been carried out on the Kenyan part of the Lake Victoria. This lake is one of the largest freshwater bodies of the world where, over the last few years environmental challenges and human impact have perturbed the ecological balance affecting the biodiversity. The objective of this research study is to define the thematic products, retrievable from satellite images, like weed abundance maps and water compound concentrations. These products, if provided with an appropriate time frequency, are useful to identify the preconditions for the occurrence of hazard events like abnormal macrophyte proliferation and to develop an up-to-date decision support system devoted to an apprised territory, environment and resource management.  相似文献   
200.
Sea ports and the related maritime activities (e.g. shipping, shipbuilding, etc.) are one of the main driver of Europe’s growth, jobs, competitiveness and prosperity. The continuously growth of shipping sectors has however introduced some environmental concerns, particularly with respect to ship-generated waste management. The port of Koper, one of the major ports on the northern Adriatic Coast, is the focus of this study. In this paper, a life cycle assessment was performed to identify and quantify the environmental impacts caused by the ship-generated waste management of port of Koper. Carcinogens substance (e.g. dioxins) and inorganic emissions, especially heavy metals, resulted to be the most critical environmental issues, while the fossil fuels consumption is reduced by recovery of ship-generated oils. Moreover, the final treatment of ship waste was found to be critical phase of the management, and the landfill have a significant contribute to the overall environmental load. These results can be useful in the identification of the best practices and in the implementation of waste management plans in ports.  相似文献   
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