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591.
Throughfall and bulk precipitation chemistry were studied for five years (June 1994–May 1999) at two high elevation forest sites (Val Gerola and Val Masino) which were known to differ in terms of tree health, as assessed by live crown condition. The ion concentration of bulk precipitation samples did not differ significantly between sites, except for Mg2+, while the throughfall concentrations differed in the measured values of H+, N-NO3, Cl, Na+, K+, DOC and weak organic acids. The results of the application of the canopy exchange model indicated a higher contribution from the dry deposition of N-NO3, N-NH4+ and H+ at Val Gerola, where the damage symptoms were more evident. In addition, the canopy leaching of Ca2+, K+ and weak organic acids were 47%, 21% and 27% higher at Val Gerola than at Val Masino. Annual SO42− deposition fluxes (21.3 kg ha−1 yr−1 at Val Masino and 23.6 kg ha−1 yr−1 at Val Gerola) were similar to those reported for moderately polluted European and U.S. sites. Annual N loads were 13.6 and 13.1 kg ha−1 yr−1 in the bulk input, and 15.0 and 18.0 kg ha−1 yr−1 in throughfall inputs, at Val Masino and Val Gerola, respectively. The contribution of the organic fraction to the total N atmospheric deposition load is significant, constituting 17% of the bulk flux and 40% of the throughfall flux. Measured nitrogen loads exceed the critical nutrient loads by several kg N ha−1 at both stations. In particular the nitrogen throughfall load at Val Gerola was about 3 times higher than the critical values.  相似文献   
592.
Environmental Science and Pollution Research - Specimens of the Cichla pinima are of ecological and economic importance in the Amazon region and are a good bioindicator species of Hg...  相似文献   
593.
Birds of prey, owls and falcons are widely used as sentinel species in raptor biomonitoring programmes. A major current challenge is to facilitate large-scale biomonitoring by coordinating contaminant monitoring activities and by building capacity across countries. This requires sharing, dissemination and adoption of best practices addressed by the Networking Programme Research and Monitoring for and with Raptors in Europe (EURAPMON) and now being advanced by the ongoing international COST Action European Raptor Biomonitoring Facility. The present perspective introduces a schematic sampling protocol for contaminant monitoring in raptors. We provide guidance on sample collection with a view to increasing sampling capacity across countries, ensuring appropriate quality of samples and facilitating harmonization of procedures to maximize the reliability, comparability and interoperability of data. The here presented protocol can be used by professionals and volunteers as a standard guide to ensure harmonised sampling methods for contaminant monitoring in raptors.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01341-9) contains supplementary material, which is available to authorized users.  相似文献   
594.
Environmental Science and Pollution Research - Solar-driven photocatalysis is a promising water-cleaning and energy-producing technology that addresses some of the most urgent engineering problems...  相似文献   
595.
Journal of Material Cycles and Waste Management - Predicting municipal solid waste (MSW) generation is fundamental in choosing and scaling the processes involved in municipal management. The...  相似文献   
596.
Brazil is a vast country and there are several scientific studies reporting sustainable behavior in its different regions. Since methodologies used in these studies differ from one another, it is hard to compare them. This paper aims to identify whether differences in sustainable behavior occur in different Brazilian regions and what differences can be identified. Through a web survey, we analyzed data from 1,489 participants, from four different regions. We identified two factors (behavior and search for information), and analyzed the differences through multivariate analysis of variance. The Northeast region had a higher score for “search for information”, while Southern regions performed better on “behavior.” The Midwest region had the worst performance for both factors. The reasons for such differences may be greatly influenced by the social/cultural context of each region. The results also show that consumers still do not use their power of choice to pressure companies to become more sustainable.  相似文献   
597.
Environmental Science and Pollution Research - The algal organic matter (AOM) is a problem in water treatment. Although the adsorption process is extensively applied to drinking water treatment,...  相似文献   
598.
Ozone and energy fluxes have been measured using the eddy covariance technique, from June to December 2004 in Castelporziano near Rome (Italy), and compared to similar measurements made in the previous year. The studied ecosystem consisted in a typical Mediterranean Holm oak forest. Stomatal fluxes have been calculated using the resistance analogy and by inverting the Penmann-Monteith equation. Results showed that the average stomatal contribution accounts for 42.6% of the total fluxes. Non-stomatal deposition proved to be enhanced by increasing leaf wetness and air humidity during the autumnal months. From a comparison of the two years, it can be inferred that water supply is the most important limiting factor for ozone uptake and that prolonged droughts alter significantly the stomatal conductance, even 2 months after the soil water content is replenished. Ozone exposure, expressed as AOT40, behaves similarly to the cumulated stomatal flux in dry conditions whereas a different behaviour for the two indices appears in wet autumnal conditions. A difference also occurs between the two years.  相似文献   
599.
Monitoring campaigns from different locations have recently shown how air concentrations of persistent semivolatile contaminants such as polychlorinated biphenyls (PCBs) often exhibit short-term (less than 24 h) variations. The observed patterns have been ascribed to different factors, such as temperature-mediated air-surface exchange and variability of planetary boundary layer (PBL) height and dynamics. Here, we present a new modeling approach developed in order to investigate the short-term variability in air concentrations of organic pollutants at a local scale. A new dynamic multimedia box model is supplied by a meteorological preprocessor (AERMET) with hourly values of air compartment height and wind speed. The resulting model is tested against an existing dataset of PCB air concentrations measured in Zurich, Switzerland. Results show the importance of such modeling approach in elucidating the short- and long-term behavior of semivolatile contaminants in the air/soil system.  相似文献   
600.

Aim of the study  

Helophytes like rush and reed are increasingly used for phytoremediation of contaminated water. This study characterises the response of rush and reed plants to chemical stressors such as chlorobenzene, benzene and methyl-tert-butyl ether. The extractable wax layer of the cuticle was chosen for detailed investigations due to its multiple, particularly, protective functions for plants and its easy availability for analysis.  相似文献   
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