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41.
This paper analyses the influence of climate change and land development on future flood risk for selected Austrian flood-prone municipalities. As part of an anticipatory micro-scale risk assessment we simulated four different inundation scenarios for current and future 100- and 300-year floods (which included a climate change allowance), developed scenarios of future settlement growth in floodplains and evaluated changes in flood damage potentials and flood risk until the year 2030. Findings show that both climate change and settlement development significantly increase future levels of flood risk. However, the respective impacts vary strongly across the different cases. The analysis indicates that local conditions, such as the topography of the floodplain, the spatial allocation of vulnerable land uses or the type of land development (e.g. residential, commercial or industrial) in the floodplain are the key determinants of the respective effects of climate change and land development on future levels of flood risk. The case study analysis highlights the general need for a more comprehensive consideration of the local determinants of flood risk in order to increase the effectiveness of an adaptive management of flood risk dynamics.  相似文献   
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We introduce an approach for establishing reference conditions (RC) for rivers of the German Baltic Sea catchment, based on predictive modelling. An extensive data set of statistics from the year 1880 was coupled with literature data, providing a comprehensive basis for the calculation of regional historical nutrient emissions into rivers, river nutrient concentrations, and nutrient loading into the sea. Four different scenarios were calculated: scenario 1 assumed RC following previously established criteria for lakes (Poikane et al. in Environ Manag 45(6):1286–1298, 2010), scenario 4 applied the nutrient emission conditions of 1880 (considering non-intensive land usage, the presence of tile drainage systems, sewer systems, and the human population from 1880), and scenarios 2 and 3 considered intermediate conditions. Our results showed that nutrient emissions from scenario 1 accounted for approximately one-tenth of the currently observed total nitrogen (TN) and total phosphorus (TP) emissions. The nutrient emissions calculated for 1880 (scenario 4) were found to be 47 % (TN) and 55 % (TP) higher than those calculated considering reference lake conditions (scenario 1). Our results suggest that RC nutrient concentrations in rivers in the German Baltic Sea catchment were clearly below 0.05 mg/l for TP and 1 mg/l for TN. This range is in accordance with historical and calculated pristine nutrient concentrations from other rivers in similar catchments.  相似文献   
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Certificate trading schemes have been discussed as a cost-efficient means of reducing urban land consumption in Germany by capping and reallocating permissions to conduct building projects. However, in contrast to the established cap & trade systems for emissions, reputation-seeking politicians would be in charge of buying and trading certificates – an aspect not considered to date. We thus present a laboratory experiment that captures politicians’ incentives connected to electoral cycles in a cap & trade scheme for land consumption, whereby tradable certificates are auctioned and grandfathered in equal shares. We find the cap & trade system to be efficient at large; yet, there are several politically relevant distortions that are aggravated by self-serving incentives. We thus identify potential problems to a cap & trade system for urban land consumption that could substantially reduce both its assumed superior efficiency and its political feasibility.  相似文献   
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A jet resonance-enhanced multiphoton ionization (REMPI) monitor was tested on a hazardous-waste-fired boiler for its ability to determine concentrations of polychlorinated dibenzodioxins and dibenzofurans (PCDDs/Fs). Jet REMPI is a real-time instrument capable of highly selective and sensitive (from parts per billion to parts per trillion) detection of a broad range of aromatic compounds, including a number of air toxic compounds. The PCDD/F toxic equivalency (TEQ) value was derived from a predetermined correlation (R 2 = 0.74) with monochlorobenzene (MClBz). This relationship was applied to nine subsequent jet REMPI on-line measurements of MClBz and parallel, standard extractive sampling for PCDD/F TEQ. For high waste-firing rates, with a range of PCDD/F TEQ values between 3.9 and 6.0 ng TEQ/m3, the TEQ values predicted by jet REMPI had a relative difference of 26% with the standard EPA Method 23 results. At low waste-firing rates (0.9–1.6 ng TEQ/m3), the relative difference increased to 219%. This limited testing shows that jet REMPI has promise as an on-line diagnostic monitor, providing feedback on the effects on PCDD/F emissions of operating parameter changes such as fuel feed interruptions or air pollution control failures.  相似文献   
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Soils developed on the sites of Australian Aboriginal oven mounds along the Murray River in SE Australia, classified as Cumulic Anthroposols under the Australian Soil Classification, are shown to have traits similar to the Terra Preta de Indio of the Amazon basin. Seven such sites were characterised and compared with adjacent soils. The Cumulic Anthroposols contained significantly (p < 0.05) more soil carbon (C), compared to adjacent non-Anthroposols. Solid-state 13C NMR spectroscopy showed that the C in the Cumulic Anthroposols was predominantly aromatic, especially at depth, confirming the presence of charcoal. Radiocarbon analysis carried out on charcoal collected from two of these sites showed that it was deposited 650 ± 30 years BP at one site and 1609 ± 34 years BP at the other site, demonstrating its recalcitrance in soil. The charcoal originated from plant material, as shown by SEM, and had high levels of Ca agglomeration on its surfaces. The Cumulic Anthroposols were shown to have altered nutrient status, with total N, P, K and Ca being significantly greater than in the adjacent soils throughout the profile. This was also reflected in the higher mean CEC of 31.2 cmol (+) kg?1 and higher pH by 1.3 units, compared to the adjacent soils. Based on the similarity of these Cumulic Anthroposols with the Terra Preta de Indio of the Amazon, we suggest that these Cumulic Anthroposols can be classified as Terra Preta Australis. The existence of these soils demonstrates that Australian soils, in temperate climates, are capable of storing C in much higher quantities than has been previously recognised, and that this capability is founded on the unique stability and properties of charred organic matter. Furthermore, the addition of charcoal appears to have improved the physical and chemical properties of these soils. Together, this provides important support for the concept of soil amendment with “biochar”, the charred residue produced by pyrolysis of biomass, as a means for sequestering C and enhancing agricultural productivity.  相似文献   
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Evolutionary theory predicts that more resources are allocated to sperm production when sperm competition is high. This prediction is supported by both comparative and experimental data on static measures of male allocation, such as testis and ejaculate size. However, resource allocation is a dynamic process, and it is therefore important to evaluate if the static measures reflect this. Such an evaluation has to our knowledge never been done. Immunocytochemical labelling with bromodeoxyuridine (BrdU) allows visualisation of cells in S-phase. BrdU becomes incorporated into cells if, and only if, they are actively undergoing DNA duplication, which is a dynamic process. The number of BrdU-positive cells in the testis can hence serve as a dynamic measure of male allocation, i.e. testicular activity. We evaluate the relationship between testis size and testicular activity in the marine flatworm Macrostomum sp. In a previous study, we showed that testis size is phenotypically plastic in this species, and that worms make larger testes when they are raised in larger groups. We use this plasticity to experimentally produce variation in testis size, and demonstrate that larger testes are associated with higher testicular activity. Moreover, testis size and testicular activity were related linearly. We have thus, for the first time, shown that testis size is a good measure of resource allocation to the male function. Moreover, increased testicular activity is probably one of the first steps in the upregulation of sperm production. It is thus expected that testicular activity is a more sensitive measure of short-term variation in male allocation than the commonly used static measures.Communicated by N. Wedell  相似文献   
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