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181.
We investigate farmers’ intentions to apply biodiversity conservation practices from a psychological perspective, using an adapted version of the theory of planned behaviour (TPB), including group norms and putting emphasis on moral norms and self-identity. The study is based on a quantitative survey (n = 99) in Belgium, analysed using confirmatory factor analyses and path analysis. Results suggest that the impact of attitudes, social norms and perceived behavioural control on intentions is almost fully mediated through moral norms and self-identity. To have a sustained impact, change actions should strive to embed biodiversity conservation into the social norms and into the good farmer identity of the farming community. While acknowledging the explanatory nature of this study, the findings could suggest another view on how to induce behavioural change.  相似文献   
182.
In this study, the indicative value of mosses as biomonitors of atmospheric nitrogen (N) depositions and air concentrations on the one hand and site-specific and regional factors which explain best the total N concentration in mosses on the other hand were investigated for the first time at a European scale using correlation analyses. The analyses included data from mosses collected from 2781 sites across Europe within the framework of the European moss survey 2005/6, which was coordinated by the International Cooperative Programme on Effects of Air Pollution on Natural Vegetation and Crops (ICP Vegetation). Modelled atmospheric N deposition and air concentration data were calculated using the Unified EMEP Model of the European Monitoring and Evaluation Programme (EMEP) of the Convention on Long-range Transboundary Air Pollution (CLRTAP). The modelled deposition and concentration data encompass various N compounds. In order to assess the correlations between moss tissue total N concentrations and the chosen predictors, Spearman rank correlation analysis and Classification and Regression Trees (CART) were applied. The Spearman rank correlation analysis showed that the total N concentration in mosses and modelled N depositions and air concentrations are significantly correlated (0.53 ≤ rs ≤ 0.68, p < 0.001). Correlations with other predictors were lower than 0.55. The CART analysis indicated that the variation in the total N concentration in mosses was best explained by the variation in NH4+ concentrations in air, followed by NO2 concentrations in air, sampled moss species and total dry N deposition. The total N concentrations in mosses mirror land use-related atmospheric concentrations and depositions of N across Europe. In addition to already proven associations to measured N deposition on a local scale the study at hand gives a scientific prove on the association of N concentration in mosses and modelled deposition at the European scale.  相似文献   
183.
There is an increasing interest in the end-of-life management of polymers present in waste electrical and electronic equipment (WEEE). This is mainly due to high recycling and recovery quotas set by the European WEEE directive, which can only be fulfilled by including the plastic fraction in recycling and recovery approaches. Previous studies identified a high material diversity and various contaminants in WEEE plastics, including heavy metals, polybrominated biphenyls (PBB), diphenyl ethers (PBDE), as well as polybrominated dibenzodioxins and dibenzofurans (PBDD/F). These substances are regulated by European directives that limit their levels in marketable products. Consequently, both material diversity and contaminants are strong arguments against material recycling and point to hazardous waste treatment. However, recent developments in the production of flame retardants and electrical and electronic goods aimed to reduce contaminants and material diversity. Thus, the present study summarises updated contaminant levels of plastic fractions of European WEEE, as well as data on materials in waste housing polymers. Material characterisation revealed housing fractions to be interesting sources for polymer recycling, which however has to implement potent material separation and/or bromine elimination techniques. With respect to contaminants, our data indicate an effective phase-out of PBB, but still high levels of PBDE and PBDD/F are found. Sources and implications for the material recycling and thermal recovery approaches are discussed in detail.  相似文献   
184.
Design criteria for planning urban sewerage/excreta management systems appropriate for developing countries as distinguished from affluent industrialized country practices.  相似文献   
185.
Size distributions of lead aerosols were obtained for 61 test periods in five urban and two remote areas of the United States. The tests were carried out under a variety of weather conditions in downtown, industrial, and residential locations of Los Angeles, the San Francisco Bay area, Chicago, Cincinnati, Philadelphia, and remote sites in Oklahoma and Arizona. Samples were obtained with a modified Goetz Aerosol spectrometer. Various fractions of the collected samples were analyzed by the dithizone method for lead and the size distributions were calculated on the basis of the chemical determinations. Size distributions were generally similar at the several sampling sites covered in the study.  相似文献   
186.
Winfried Schröder  Stefan Nickel  Simon Schönrock  Michaela Meyer  Werner Wosniok  Harry Harmens  Marina V. Frontasyeva  Renate Alber  Julia Aleksiayenak  Lambe Barandovski  Alejo Carballeira  Helena Danielsson  Ludwig de Temmermann  Barbara Godzik  Zvonka Jeran  Gunilla Pihl Karlsson  Pranvera Lazo  Sebastien Leblond  Antti-Jussi Lindroos  Siiri Liiv  Sigurður H. Magnússon  Blanka Mankovska  Javier Martínez-Abaigar  Juha Piispanen  Jarmo Poikolainen  Ion V. Popescu  Flora Qarri  Jesus Miguel Santamaria  Mitja Skudnik  Zdravko Špirić  Trajce Stafilov  Eiliv Steinnes  Claudia Stihi  Lotti Thöni  Hilde Thelle Uggerud  Harald G. Zechmeister 《Environmental science and pollution research international》2016,23(11):10457-10476
For analysing element input into ecosystems and associated risks due to atmospheric deposition, element concentrations in moss provide complementary and time-integrated data at high spatial resolution every 5 years since 1990. The paper reviews (1) minimum sample sizes needed for reliable, statistical estimation of mean values at four different spatial scales (European and national level as well as landscape-specific level covering Europe and single countries); (2) trends of heavy metal (HM) and nitrogen (N) concentrations in moss in Europe (1990–2010); (3) correlations between concentrations of HM in moss and soil specimens collected across Norway (1990–2010); and (4) canopy drip-induced site-specific variation of N concentration in moss sampled in seven European countries (1990–2013). While the minimum sample sizes on the European and national level were achieved without exception, for some ecological land classes and elements, the coverage with sampling sites should be improved. The decline in emission and subsequent atmospheric deposition of HM across Europe has resulted in decreasing HM concentrations in moss between 1990 and 2010. In contrast, hardly any changes were observed for N in moss between 2005, when N was included into the survey for the first time, and 2010. In Norway, both, the moss and the soil survey data sets, were correlated, indicating a decrease of HM concentrations in moss and soil. At the site level, the average N deposition inside of forests was almost three times higher than the average N deposition outside of forests.  相似文献   
187.
The lower Passaic River in northern New Jersey (USA) has been heavily industrialized since the mid-nineteenth century and its shoreline and aquatic habitats degraded or destroyed. Similar to other urban systems, Passaic River sediments, both surface and buried, historically have contained elevated levels of numerous contaminants that may pose risks to ecological receptors and humans. Sediments from 15 stations in the lower Passaic River and 3 reference stations in the Mullica River in southern New Jersey were sampled in 1999 and characterized for chemical contamination, toxicity, and impairment of the benthic community. The objective of this study was to determine the incidence, degree, and nature of degraded surficial sediments in the area to support subsequent plans for restoration of the system. Results demonstrated that Passaic River sediments had concentrations of many organic and inorganic contaminants at levels significantly greater than the reference area and effect-based guidelines. Sediments were toxic to marine amphipods at 11 stations and the benthic assemblages were impaired relative to the reference area at all stations. The weight-of-evidence of this sediment quality triad (SQT) assessment indicates that impacts from multiple contaminants are occurring throughout the lower Passaic River and, that these impacts must be evaluated further and addressed as part of ongoing restoration initiatives for the river.  相似文献   
188.
For spatial linear regression, the traditional approach to capture spatial dependence is to use a parametric linear mixed-effects model. Spline surfaces can be used as an alternative to capture spatial variability, giving rise to a semiparametric method that does not require the specification of a parametric covariance structure. The spline component in such a semiparametric method, however, impacts the estimation of the regression coefficients. In this paper, we investigate such an impact in spatial linear regression with spline-based spatial effects. Statistical properties of the regression coefficient estimators are established under the model assumptions of the traditional spatial linear regression. Further, we examine the empirical properties of the regression coefficient estimators under spatial confounding via a simulation study. A data example in precision agriculture research regarding soybean yield in relation to field conditions is presented for illustration.  相似文献   
189.
Aromatase activity was determined in brain and gonads of wild bream collected along the river Elbe, Germany, and correlated with other endocrine and reproductive endpoints such as plasma sex steroid concentrations, secondary sex characteristics (STI), plasma vitellogenin, gonad size (GSI), and maturation stages of germ cells (MS) that were reported for the same fish in a previous study. Furthermore, regional patterns of aromatase activity were correlated to a number of environmental factors such as exposure to environmental contaminants and parasitism. While aromatase activity was not detectable in the gonads of male and female fish with the assay used, fish of both genders revealed relatively great brain enzyme activities. As for most of the endocrine and reproductive parameters, with the exception of plasma testosterone (T), aromatase activities were significantly less in fish from a river stretch characterized by elevated exposures to organic contaminants and metals. Brain aromatase activity was positively and significantly correlated with plasma estradiol (E2) and MS in females, and showed a similar trend with plasma 11-ketotestosterone (11KT) and STI in males. No comparable trend occurred for T. This decrease of the reproductively relevant hormones 11KT and E2 may be indicative of a disruption of the last step in sex hormone synthesis, a hypothesis that was supported for E2 by the strong (R2=0.78, p<0.05) linear regression between aromatase activity and E2 in female bream. It is also hypothesized that the effects on brain aromatase activity were likely to be related to the disruption of other reproductive parameters including sexual maturity and expression of secondary sex characteristics. Although a number of factors such as exposure to pollutants and prevalence of the tapeworm Ligula intestinalis correlated with the suppression of aromatase activity, the exact causes for the regional decrease in brain aromatase activity remain unclear due to inconsistencies of these correlations between sampling events or gender.  相似文献   
190.
The combination of biomonitoring with standardized grass cultures and deposition monitoring of antimony (Sb), lead (Pb) and 12 polycyclic aromatic hydrocarbon compounds (PAH) was carried out in the conurbation of Munich, Germany in 1993 and resumed at the German-Czech border in 1995. Results from different location types in different areas and years seem to be comparable for Sb and PAH, because relevant background data fit in the same range. Biomonitoring reveals a seasonal course of PAH accumulation. Mean PAH contents are found to be significantly higher in grass cultures at locations along heavily traveled roads, compared to sites in living areas or in a rural background. The traffic related PAH bioaccumulation of both regions fits in the same range, although traffic composition is different and traffic density is ten times smaller at the German-Czech border. Correlation of Pb and Sb bioaccumulation in grass vs. deposition suggested abrasions of brake linings and tires to be one possible emission source. This might be the explanation for the mean contents of Pb and Sb in grass cultures at traffic locations in Munich exceeding those in living or rural areas. Deposition (Bergerhoff method) indicates analogous pollution dynamics in association with traffic. Pb bioaccumulation and deposition along the main roads at the German-Czech border show wider ranges compared to Munich. On the whole, Pb and Sb values at border traffic are found to be lower than those in Munich two years previously.  相似文献   
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