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41.
This paper discusses climate, land, energy and water (CLEW) interactions in Burkina Faso. It shows that integrated assessments of resource use at the national level can provide important insights and benefits, especially for a resource constrained least developed country. Agricultural policy is shown to have strong implications for energy use, whereas energy policies are found to be strongly interrelated with water constraints. Without an integrated and coordinated approach, strategy and policy formulation efforts to increase energy, food and water security could become both incoherent and counter‐productive.  相似文献   
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The atmospheric concentrations of benzene, toluene, ethylbenzene and isomeric xylenes (BTEX) in a medium-sized town (S. Maria Capua Vetere, about 32000 inhabitants, Southern Italy) have been determined during working days and weekends in 2006. The procedure used was 24h passive adsorption by samplers distributed throughout the town followed by GC/MS analysis. On a yearly base, the arithmetic mean benzene concentrations were above the limit required by the 2000/69/CE European Directive. The Pearson correlation coefficients of the 24h geometric mean BTEX concentrations were indicative of stationary sources of toluene located in a well circumscribed area of the urban territory, active only during the working days and not officially recognized. The results highlight the effectiveness of the statistical approach used in this study for the identification of pollutant sources.  相似文献   
43.
Monitoring and mapping shrimp farms, including their impact on land cover and land use, is critical to the sustainable management and planning of coastal zones. In this work, a methodology was proposed to set up a cost-effective and reproducible procedure that made use of satellite remote sensing, object-based classification approach, and open-source software for mapping aquaculture areas with high planimetric and thematic accuracy between 2005 and 2008. The analysis focused on two characteristic areas of interest of the Tam Giang-Cau Hai Lagoon (in central Vietnam), which have similar farming systems to other coastal aquaculture worldwide: the first was primarily characterised by locally referred “low tide” shrimp ponds, which are partially submerged areas; the second by earthed shrimp ponds, locally referred to as “high tide” ponds, which are non-submerged areas on the lagoon coast. The approach was based on the region-growing segmentation of high- and very high-resolution panchromatic images, SPOT5 and Worldview-1, and the unsupervised clustering classifier ISOSEG embedded on SPRING non-commercial software. The results, the accuracy of which was tested with a field-based aquaculture inventory, showed that in favourable situations (high tide shrimp ponds), the classification results provided high rates of accuracy (>95 %) through a fully automatic object-based classification. In unfavourable situations (low tide shrimp ponds), the performance degraded due to the low contrast between the water and the pond embankments. In these situations, the automatic results were improved by manual delineation of the embankments. Worldview-1 necessarily showed better thematic accuracy, and precise maps have been realised at a scale of up to 1:2,000. However, SPOT5 provided comparable results in terms of number of correctly classified ponds, but less accurate results in terms of the precision of mapped features. The procedure also demonstrated high degrees of reproducibility because it was applied to images with different spatial resolutions in an area that, during the investigated period, did not experience significant land cover changes.  相似文献   
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Many studies have focused their attention on the determination of elements of toxicological and environmental interest in atmospheric particulate matter using analytical techniques requiring chemical treatments. The instrumental nuclear activation analysis technique allows achieving high sensitivity, good precision, and excellent limit of detection without pretreatment, also considering the problems related to the radioisotope characteristics (e.g., half-life time, interfering reactions, spectral interferences). In this paper, elements such as Al, As, Br, Cl, Cu, I, La, Mg, Mn, Na, Sb, Si, Ti, and V are studied in atmospheric PM10 sampled in downtown Rome: The relative radionuclides after activation of the sample are characterized by very short (ranging from 2.24 to 37.2 min) and short (ranging from 2.58 h to 2.70 days) half-lives. Furthermore, As, Br, La, Mn, and Sb were also determined for evaluating the aerosol characteristics. The results, elaborated considering the matrix effects and the interfering reaction contribution to the radioisotope formation (e.g., 28Al generated by both (n,γ) reaction from 27Al and (n,p) reaction from 28Si), show interesting values of As (0.3–6.1 ng m?3), Cu (22–313 ng m?3), Mn (17–125 ng m?3), V (7–63 ng m?3), higher than those determined in an area not influenced by autovehicular traffic, and significant levels of I (1–11 ng m?3) and Ti (25–659 ng m?3) in Rome PM10. The other elements show a pattern similar to the very few data present in the literature. It should be underlined the good correlation (r 2) of Al vs. Mg (0.915) and Al vs. La (0.726), indicating a same sources for these species as well as Br–Sb showing a little lower correlation (0.623). This last hypothesis is confirmed by the study of the enrichment factors: Sb and Br may be attributed to anthropogenic sources; Cu, Cl, and I show a mixed origin (natural and anthropogenic), whereas Al, Si, Ti, Mn, Na, Mg, and As are of crustal origin. For having more information, a statistical approach based on the principal component analysis and the canonical discriminant analysis has been performed: All the samples (except one) are grouped in a cluster, and elements such as As, Br, Cu, I, La, Mn, Sb, Ti, and V are highly correlated, whereas Na and Cl and Mg and Al assemble in two different clusters. Finally, a comparison with other similar studies is reported showing interesting values for Al, As, Mg, Mn, and Ti.  相似文献   
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Environmental Science and Pollution Research - Sediment toxicity plays a fundamental role in the health of inland fish communities; however, the assessment of the hazard potential of contaminated...  相似文献   
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After a critical analysis of the strategies for conservation of the environment in Latin America and of large-scale development projects (agriculture and livestock raising, mining and electrical power plants) in the Amazon region of Brazil, this paper deals with the use of high-resolution satellite imagery for environmental monitoring. Two areas were considered in the study, Tucurui and Altamira. Spot/XS and Landsat/TM multispectral images were used, together with color aerial photographs of these areas. A computer-assisted visual interpretation procedure was employed to analyze images, and linear multispectral transformation was applied in selected subscenes in order to improve information extraction. The results indicate that high-resolution satellite imagery is generally compatible with the scale of the environmental problems in Amazonia and is a very efficient source of detailed information at a local scale on many aspects of the environment, in particular for monitoring changes over time in selected areas. Therefore, commercial satellite imagery, processed by specialized software, can accommodate a variety of analysis needs for decision makers and can also be an effective means of verification of international agreements on conservation of the environment in Amazonia.  相似文献   
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