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71.
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   
72.
The injection of CO2 at the Ketzin storage site and the chemical detection of its arrival in the observation well allowed testing of different numerical simulation codes. ECLIPSE 100 (E100, black-oil simulator), ECLIPSE 300 (E300, compositional CO2STORE) and MUFTE-UG were used for predictive modelling applying a constant injection rate of 1 kg s?1 CO2 and for a history match applying the actual variable injection rate which ranged from 0 to 0.7 kg s?1 and averaged 0.23 kg s?1. The geological model applied, is based on all available geophysical and geological information and has been the same for all programs.The results of the constant injection regime show a good agreement among the programs with a discrepancy of 21–33% for the CO2 arrival times. However, it is determined from the comparison of the cumulative mass of CO2 at the time of CO2 arrival that the injection regime is an important factor for the accurate prediction of CO2 migration within a saline aquifer. Comparing the actual variable injection regime with the simulations applying a constant injection rate the results are relatively inaccurate.Regarding the actual variable injection regime, which was evaluated using all three simulators, the computational results show a good agreement with the data actually measured at the first observation well. Here, the calculated arrival times exceeded the actual ones by 8.1% (E100), 9.2% (E300) and 17.7% (MUFTE-UG).It can be concluded that irrespective of the deviations of the simulations, due to combinations of different codes and slight differences in input parameters, all three programs are well equipped to give a reliable estimate of the arrival of CO2. Deviations in the results mainly occur due to different input data and grid size choices done by the different modelling teams working independently of each other. Deviations of the simulations results compared to the actual CO2 arrival time result from uncertainties in the implementation of the geological model, which was set up based on well log data and analogue studies.  相似文献   
73.
Many anadromous fish species, when migrating from the sea to spawn in fresh waters, can potentially be a valuable prey for larger predatory fish, thereby efficiently linking these two ecosystems. Here, we assess the contribution of anadromous fish to the diet of European catfish (Silurus glanis) in a large river system (Garonne, southwestern France) using stable isotope analysis and allis shad (Alosa alosa) as an example of anadromous fish. Allis shad caught in the Garonne had a very distinct marine δ13C value, over 8‰ higher after lipid extraction compared to the mean δ13C value of all other potential freshwater prey fish. The δ13C values of European catfish varied considerably between these two extremes and some individuals were clearly specializing on freshwater prey, whereas others specialized on anadromous fish. The mean contribution of anadromous fish to the entire European catfish population was estimated to be between 53% and 65%, depending on the fractionation factor used for δ13C.  相似文献   
74.
This study aimed at cross-border mapping metal loads in mosses in eight European countries in 1990, 1995, and 2000 and at investigating confounding factors. Geostatistics was used for mapping, indicating high local variances but clear spatial autocorrelations. Inference statistics identified differences of metal concentrations in mosses on both sides of the national borders. However, geostatistical analyses did not ascertain discontinuities of metal concentrations in mosses at national borders due to sample analysis in different laboratories applying a range of analytical techniques. Applying Classification and Regression Trees (CART) to the German moss data as an example, the local variation in metal concentrations in mosses were proved to depend mostly on different moss species, potential local emission sources, canopy drip and precipitation.  相似文献   
75.
From September 1985 to March 1992, 804 amniotic fluid samples from 64 different diagnostic centres of the Federal Republic of Germany were sent to our laboratory exclusively for rapid karyotyping. The average time needed for notification of the analysed karyotype was 4·65 days when the ‘pipette method’ was used for chromosome harvesting and 5·97 days when the ‘in situ’ technique was used. The overall incidence of chromosome aberrations was 15·3 per cent. Data are presented about the likelihood of abnormal ultrasound findings being caused by chromosome aberrations. These findings include polyhydramnios, oligohydramnios, growth retardation, fetal effusions, neural tube defects, craniofacial defects, heart defects, gastroschisis and omphalocele, gastrointestinal tract defects, urinogenital defects, and limb defects. In future, such data need to contain larger numbers of cases for each week of gestation. This will improve the risk evaluation for each case with abnormal ultrasound findings, which should lead to better management during pregnancy, delivery, and postnatal care for those who require rapid karyotyping.  相似文献   
76.
The 'pipette method' is introduced as a method of prenatal diagnosis which is in competition with the 'in situ' and the 'trypsinization' technique. It is sufficiently standardized for routine diagnosis and the banding techniques currently used in prenatal diagnosis (G, Q, C-banding and NOR) have been adapted for it. In 180 cases from 27 different centres, the 'pipette method' was employed for chromosomal harvesting in order to save time. An average of 6·6 days was taken to achieve a result. There was a pathological karyotype in 28 cases (16·1 per cent) and this high proportion can be related to cases where ultrasound scan has led to a diagnosis of 'suspected chromosomal abnormality'. This technique is also of use in advanced stages of pregnancy. The early recognition of the fetal karyotype can contribute to the future management of the pregnancy. The 'pipette method' can also be used in chromosomal harvesting of tumour cells and fibroblast cultures.  相似文献   
77.
The concentration profile of 40 polyfluoroalkyl substances (PFAS) in surface water along the River Rhine watershed from the Lake Constance to the North Sea was investigated. The aim of the study was to investigate the influence of point as well as diffuse sources, to estimate fluxes of PFAS into the North Sea and to identify replacement compounds of perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA). In addition, an interlaboratory comparison of the method performance was conducted. The PFAS pattern was dominated by perfluorobutane sulfonate (PFBS) and perfluorobutanoic acid (PFBA) with concentrations up to 181 ng/L and 335 ng/L, respectively, which originated from industrial point sources. Fluxes of ΣPFAS were estimated to be ∼6 tonnes/year which is much higher than previous estimations. Both, the River Rhine and the River Scheldt, seem to act as important sources of PFAS into the North Sea.  相似文献   
78.
Depending on gender and activity, overcrowding and safety concerns may detract from urban green space use. Differences in use displacement intentions from a recreational trail in a forest in Vienna were investigated for male and female walkers as well as male and female dog-walkers (N = 425) using an image-based stated preference model. The trail scenarios were depicted as digitally calibrated images that systematically displayed combinations of levels of crowding with different mixes of user types and visitor behaviour. Visitors were asked whether the presented recreation scenario was so unacceptable that they would shift their use away from the presented trail. Hours and days of stated non-use of the recreation trail by various user groups are estimated by integrating the results of the behavioural model with annual visitation data. Use displacement intentions differed by gender and activity. High use levels were a greater concern for all respondents than very low use levels, particularly for female dog-walkers. However, only a small proportion of the recorded hours were heavily used. Safety concerns about very low use levels reduced the potential times of forest use for female walkers without a dog.  相似文献   
79.
High spatial resolution maps of deposition loads in Germanyare produced as an input for abatement strategy research andfor critical loads exceedance calculations on a nationalscale. In this paper methods ofmapping total deposition loads in Germany and preliminarymaps of nitrogen and sulphur deposition loads for the year1993 are presented. A comparison of these mapping resultswith EMEP deposition mapping results has been carried out.The differences in the results of the German national and theEuropean EMEP mapping, due to different databases anddifferent methods, are quantified and discussed. Highresolution maps of deposition loads are compared to Europeanlow resolution maps on the same temporal and spatial scale,assuming that on average both should lead to similar results.However, the average differencescalculated for 23 EMEP 150 × 150 km2 grid cells over Germanywere found to be 33% higher for sulphur (S) total depositionby the German method 65% higher for S dry deposition and1% lower for S wet deposition. The German results fornitrogen (N) total deposition are 2% higher than the EMEPresult 22% higher for N dry deposition and 10% lower for Nwet deposition.  相似文献   
80.
Journal of Polymers and the Environment - PLA has aroused industrial and scientific interest in recent years, mainly due to its biodegradable character. However, PLA is brittle and displays low...  相似文献   
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