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无论从经济还是从自然保护角度,冲积平原和三角洲的社会压力都很大.随着经济的发展及大坝增高,由于预期的损失上升和更深的洪水,洪水风险在逐渐增加.全球变化,社会需求变化了,人们的观念也变化了,需要修订长期的洪水风险管理战略.而修订洪水风险管理战略应以柔性战略替代过去以加高大坝为主的刚性战略.柔性战略为主的洪水风险管理就意味着允许洪水临时性大面积泛滥,通过改变土地利用方式减少洪水灾害损失.这样的战略是基于风险管理和"与洪水共生存"的理念提出的,完全替代了过去的灾害控制观念.荷兰三角洲地区是世界人口密度最大区域之一,在这里,灵活的柔性洪水风险管理战略水文功能和"可持续的标准"被详细阐述和评估.  相似文献   
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Calamagrostis villosa has recently expanded in Nardus stricta-dominated sub-alpine grassland of the Giant Mountains (Krkono?e/Karkonosze, the Czech Republic). To investigate whether this expansion has been promoted by high nitrogen deposition or by the cessation of agricultural management, grassland plots dominated by C. villosa were manipulated with four treatments: control (Con), fertilised (Fer), cut (Cut) and cut–fertilised (Cut–Fer). NH4NO3 was used at the rate of 30 kg N ha?1 and fertilisation and cutting were performed once a year after data collection in late July between 2000 and 2006.Plant species composition (analysed by RDA) was significantly influenced by cutting but not by fertilisation. Cutting reduced the cover, biomass, sward height and tiller density of C. villosa. Seedlings of N. stricta and panicles of C. villosa were recorded only in plots with cutting management.To investigate the effect of treatments on the spread of C. villosa, grassland sods dominated by N. stricta were transplanted into the experimental plots. Six years later, the density and cover of C. villosa spreading into the N. stricta sods were highest in Fer treatment.C. villosa was recognised as a defoliation-sensitive species and this sensitivity cannot be overcome by an increase in N supply. Recent expansion of C. villosa in the sub-alpine grassland can by explained by a long-term succession after the cessation of agricultural management and an increase in the N availability in recent decades.  相似文献   
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Leigh syndrome (LS) is a mitochondrial encephalopathy that is caused by a mutation either in the mitochondrial DNA (mtDNA) or in the nuclear encoded genes of the mitochondrial proteins. Prenatal diagnosis of defects in the mtDNA is usually problematic because of mtDNA heteroplasmy and tissue specificity. However, the mutations T8993 G/C in the ATP synthase subunit 6 gene of the mtDNA show a more even tissue distribution and do not appear to change significantly over time. There are only few reports of prenatal diagnosis of the T8993G mutation in Leigh disease. Here we describe the first prenatal genetic testing of T8993C in a fetus of a mother whose previous child had died of Leigh syndrome due to the T8993C mutation. Mutant load in the chorionic villus sample (CVS) as well as in amniocytes was undetectable, thus predicting a very high likelihood of an unaffected outcome, indicative of a healthy baby. The diagnosis was confirmed after birth. Gathering data on the prenatal diagnosis of mtDNA mutations is of great importance so that prenatal diagnosis of both T8993G and T8993C mutations can be offered routinely. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
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Journal of Material Cycles and Waste Management - Bottom ash is the main solid residue from municipal solid waste incineration (MSWI). The material can be utilised in the construction industry but...  相似文献   
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ABSTRACT

Old cadastral maps represent a historical reference dataset for long-term land-use reconstructions. This study presents identification of inconsistencies in the nineteenth century Franziscean cadastre, one of the largest sets of old cadastral maps worldwide, by comparing three versions of the maps and written documents created in the same period. We identified all parcels and their land-use in the four sub-sources in six study areas. The overall share of inconsistencies among 5 771 identified parcels is 7.4%, with the biggest share of inconsistency in agroforestry and forestry classes. The most frequent inconsistencies are of ‘Not differentiable land use’ (n = 212) and ‘Different land-use’ categories across the sub-sources (n = 113). We conclude that the frequency of uncertainties in old cadastral maps may limit the validity of historical land-use reconstructions, affecting the eventual restoration and management efforts based on such data. We provide a summary for the use of Franziscean cadastre.  相似文献   
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Environmental Science and Pollution Research - The utilisation of waste wood from furniture production brings new problems connected with an incomplete thermochemical decomposition of additives...  相似文献   
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A long-term pilot-scale H2-based membrane biofilm reactor (MBfR) was tested for removal of nitrate from actual groundwater. A key feature of this second-generation pilot MBfR is that it employed lower cost polyester hollow fibers and still achieved high loading rate. The steady-state maximum nitrate surface loading at which the effluent nitrate and nitrite concentrations were below the Maximum Contaminant Level (MCL) was at least 5.9 g·N·(m2·d)?1, which corresponds to a maximum volumetric loading of at least 7.7 kg·N·(m3·d) ?1. The steady-state maximum nitrate surface area loading was higher than the highest nitrate surface loading reported in the first-generation MBfRs using composite fibers (2.6 g·N·(m2·d)?1). This work also evaluated the H2-utilization efficiency in MBfR. The measured H2 supply rate was only slightly higher than the stoichiometric H2-utilization rate. Thus, H2 utilization was controlled by diffusion and was close to 100% efficiency, as long as biofilm accumulated on the polyester-fiber surface and the fibers had no leaks.  相似文献   
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