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891.
892.
The release of inorganic and organic contaminants from municipal solid waste incinerator (MSWI) bottom ash is controlled to a large extent by the release of dissolved organic carbon (DOC), and in particular by the reactive humic (HA) and fulvic acids (FA) subfractions of DOC. The properties of organic matter contributing to the release of DOC, HA and FA are, therefore, important for environmental risk assessment. In this study we have quantitatively measured the carbon speciation, and its relation with the leaching of Cu, in three fresh and carbonated MSWI bottom ash samples. Results show that up to only 25% of loss on ignition (LOI) consists of organic carbon (OC), while about 17% of OC in the three samples consists of HA and FA. Up to 50% of DOC in MSWI bottom ash leachates was identified as fulvic acid (FA). This value is substantially higher than previously estimated for these MSWI bottom ash samples and is consistent with the higher recovery of the new method that was applied. The results of this study imply that methods focusing on specific carbon fractions are more appropriate for assessment of environmentally relevant organic carbon species than the measurement of LOI.  相似文献   
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Perinatal survival rates after intrauterine transfusions (IUT) for red cell alloimmunisation now exceed 90%, which demonstrates the safety and efficacy of one of the most successful procedures in fetal therapy. However, improved perinatal survival could lead to an increased number of children with long-term disabilities. The importance of long-term follow-up studies in fetal therapy lies in both the necessity of evaluation of antenatal management as well as in evidence-based preconceptional and prenatal counselling. This review describes the possible long-term cardiovascular and neurodevelopmental sequelae after IUT treatment for different indications including red cell alloimmunisation, parvovirus B19 infection, fetomaternal haemorrhage and twin anaemia-polycythaemia sequence. © 2013 John Wiley & Sons, Ltd.  相似文献   
895.
Gender in integrated water management: an analysis of variation   总被引:1,自引:0,他引:1  
Gender is an important variable in water use, policy, and intervention. This article explores this variation and its policy implications. Concepts are applied in several case studies to draw generic conclusions. Variation is related to the purpose of water use (consumptive or productive) and to the local, culture-specific patterns of the intra-household organization of consumption for family welfare (which includes domestic water provision) and income-generation (for which water is an input, especially in rural areas). For domestic water use, the intra-household sharing of unpaid domestic responsibilities is a key gender issue. Water for productive use, on the other hand, is embedded in the gendered organization of household economic activity, as elaborated for smallholder-irrigated agriculture. In female-managed and dual farming systems, where a high proportion of farm decision-makers are women, irrigation agencies need to better target their support. In male-managed farming systems, however, the majority of women lack their own farm enterprise in which water is an input. Women's access to land, markets and credits besides access to water, is at stake. To conclude, given the strong variation in water use along gender lines, gender analysis is indispensable for any concrete water policy and intervention.  相似文献   
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899.
The correlation between climatic changes and the numbers of trees in the generations of Siberian spruce (Picea obovata Ledeb.) in subgoltsy tree stands of the Southern Urals was analyzed over the past 200 years. The results showed that the most abundant generations appeared in 1809–1816, 1821–1827, 1839–1845, 1850–1867, 1875–1887, 1891–1896, 1900–1904, 1911–1918, 1923–1932, 1944–1952, 1958–1966, and 1975–1995. Their formation proved to be related to the improvement of thermal conditions of the warm season during the five to seven years before and after the emergence of trees and conditions of the cold season in the year of their emergence, as well as to the periods of increased snow depth in late April in the years 27–32 of tree growth.  相似文献   
900.
As part of the UN-ECE Intensive Monitoring Program, data on precipitation, throughfall and soil solution concentrations are measured on a regular basis in approximately 300 forest stands. These data were used to construct element budgets for European forests. To construct such budgets drainage fluxes have to be modeled. In this paper, the research chain from model selection to data derivation and application of the selected model to 245 of the 300 sites is described. To select a suitable hydrological model the Cl- balance method, two capacity models (a multi and a single layer version) and a Darcy model have been applied to two forest sites. The results indicate that drainage fluxes calculated with the Darcy model are more accurate than fluxes derived with the capacity model, in particular in situations where water availability is limited. The Darcy model was applied to the sites using a mixture of generic data and site data. Despite the use of generic data, the calculated drainage fluxes appear feasible. Median transpiration fluxes were 350 mm and the lowest values are found in northern Europe and highest values are found in central Europe. Median drainage fluxes were 150 mm yr-1 with the highest values in areas with high rainfall. Uncertainty analyses indicate that the use of local instead of interpolated meteorological data leads to lower drainage fluxes at 70% of the sites. The median deviation in calculated drainage fluxes is 20 mm yr-1. The use of local soil data had little impact on the calculated fluxes.  相似文献   
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