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101.
102.
Developing strategies to mitigate or to adapt to the threats of floods is an important topic in the context of climate changes. Many of the world’s cities are endangered due to rising ocean levels and changing precipitation patterns. It is therefore crucial to develop analytical tools that allow us to evaluate the threats of floods and to investigate the influence of mitigation and adaptation measures, such as stronger dikes, adaptive spatial planning, and flood disaster plans. Up until the present, analytical tools have only been accessible to domain experts, as the involved simulation processes are complex and rely on computational and data-intensive models. Outputs of these analytical tools are presented to practitioners (i.e., policy analysts and political decision-makers) on maps or in graphical user interfaces. In practice, this output is only used in limited measure because practitioners often have different information requirements or do not trust the direct outcome. Nonetheless, literature indicates that a closer collaboration between domain experts and practitioners can ensure that the information requirements of practitioners are better aligned with the opportunities and limitations of analytical tools. The objective of our work is to present a step forward in the effort to make analytical tools in flood management accessible for practitioners to support this collaboration between domain experts and practitioners. Our system allows the user to interactively control the simulation process (addition of water sources or influence of rainfall), while a realistic visualization allows the user to mentally map the results onto the real world. We have developed several novel algorithms to present and interact with flood data. We explain the technologies, discuss their necessity alongside test cases, and introduce a user study to analyze the reactions of practitioners to our system. We conclude that, despite the complexity of flood simulation models and the size of the involved data sets, our system is accessible for practitioners of flood management so that they can carry out flood simulations together with domain experts in interactive work sessions. Therefore, this work has the potential to significantly change the decision-making process and may become an important asset in choosing sustainable flood mitigations and adaptation strategies.  相似文献   
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104.
Stable carbon isotopes are important tools to assess potential storage sites for CO2, as they allow the quantification of ionic trapping via isotope mass balances. In deep geological formations high p/T conditions need to be considered, because CO2 dissolution, equilibrium constants and isotope fractionation of dissolved inorganic carbon (DIC) depend on temperature, pressure and solute composition. After reviewing different approaches to account for these dependencies, an expanded scheme is presented for speciation and carbon isotope fractionation of DIC and dissolution of CaCO3 for pCO2 up to 100 bar, pH down to 3 and temperatures of up to 200 °C. The scheme evaluates the influence of respective parameters on isotope ratios during CO2 sequestration. The pCO2 and pH are the dominant controlling factors in the DIC/δ13C/pH system. The fugacity of CO2 has major impact on DIC concentrations at temperatures below 100 °C at high pCO2. Temperature dependency of activities and equilibrium dominates at temperatures above 100 °C. Isotope ratios of DIC are expected to be about 1–2‰ more depleted in 13C compared to the free CO2 at pCO2 values above 10 bar. This depletion is controlled by carbon isotope fractionation between CO2 and H2CO3* which is the dominant species of DIC at the resulting pH below 5.  相似文献   
105.
The age specific patterns of reproduction and mortality dictated by the life history of an organism apply to potential invaders as well as resident species of an area, but whether certain life history traits are more invasive than others is an unresolved issue. We analyze a two-population system of an invading and a resident species and test the effects of age on the probability to invade when the organisms are iteroparous or semelparous. The life history characteristics of the populations are projected in Leslie matrices, and the probability that the invader exceeds different population sizes is calculated by Monte Carlo analysis. The simulations show that (a) the invasion probability of an iteroparous organism increases with age until the individuals introduced are mature for first reproduction, and then becomes independent of age; (b) the invasion probability is more age sensitive for iteroparous organisms with high juvenile mortality (Type III organisms) than for those with a lower (Type I); (c) invading semelparous organisms are most affected by competition from resident organisms; (d) variations in vital rates of semelparous residents have greater influence on the invasion probability of an iteroparous organism than variations in traits of the invader.  相似文献   
106.
Dredging water reservoirs is necessary to maintain accumulation capacity and to prevent floodings. As a first step, the quality of the bed sediments in water reservoirs must be determined before dredging operations. In this study, sediment samples from 34 stations of three selected water reservoirs (Zemplinska Sirava, Velke Kozmalovce, and Ruzin) were collected to investigate concentrations, distributions, and hazards of polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) and to predict their possible sources. Total PCB concentrations were in the range of 20.4 to 2,325?ng/g. The maximum concentrations of PCBs were found in sediments from Zemplinska Sirava, which is in the vicinity of a former manufacturer of PCBs. The composition of PCBs was characterized by tri- and hexa-CB congeners, indicating the influence of contamination from the use of specific Delor mixtures, formerly produced and massively used on the territory of Slovakia. The data showed that the highest total PAH concentrations were associated with the sediments from the Velke Kozmalovce, ranging from 7,910 to 29,538?ng/g. On the other hand, the lowest total PAH concentrations (84?C631?ng/g of dry weight) were found in the sediments of Zemplinska Sirava, an important recreational area in eastern Slovakia. The distribution of individual PAHs was similar among the three water reservoirs, and this, together with principal component analysis and diagnostic PAH ratios, suggests mainly pyrolytic contamination of the sediments. However, petrogenic inputs appear to be important in the Zemplinska Sirava sediments.  相似文献   
107.
A new bolosaurid parareptile, Belebey chengi sp. nov., is described from Dashankou, Gansu Province, China, a Middle Permian locality which is known mostly for its therapsid fauna. The material consists of well-preserved mandibular and anterior skull remains and currently represents the largest and latest surviving member of Bolosauridae. Phylogenetic analysis of bolosaurid interrelationships, the first analysis of any clade of Early Permian parareptiles, indicates that the new taxon groups consistently with the other (Russian) members of the genus Belebey, and forms the sister clade to the genus Bolosaurus from North America. The Early Permian Eudibamus cursoris from Germany falls into the basal most position within Bolosauridae. Our analysis also shows that the split between the main bolosaurid lineages must have occurred near or before the Permo-Carboniferous boundary and that the paleo-equatorial region of Laurasia probably served as the center of origination for these parareptiles. A similar pattern can be found in other clades of Paleozoic amniotes, suggesting that this may be the general trend in early amniote evolution.  相似文献   
108.
The Clean Development Mechanism (CDM) has successfully demonstrated that market-based mechanisms can achieve some cost effective emissions reductions in developing countries. However the distribution of CDM projects has been extremely uneven across countries and regions, and a few technologies and sectors have dominated the early stages of CDM experience. This has caused some to question whether the CDM has fallen short of its potential in contributing to sustainable development. We review the broad patterns of CDM project approvals and evaluate 10 CDM projects according to their sustainability benefits. The difficulty of defining “sustainable development” and the process of defining criteria by individual non-Annex 1 governments has meant that sustainable development concerns have been marginalized in some countries. Given these observed limitations, we present possible CDM policy futures, focusing on the main proposals for a post-2012 climate regime. Five options for enhancing the sustainable development benefits in the CDM are discussed, including proactive approaches to favour eligibility of emission reduction projects which ensure such co-benefits.  相似文献   
109.
The Kyoto Protocol's Clean Development Mechanism (CDM) has had relatively little success in Africa due to a number of factors. Increases in agricultural soil carbon have strong benefits for soil health as well as potential for carbon sequestration, but such projects are currently excluded from the CDM and other offset mechanisms. Small-scale biochar systems with net emission reductions may hold a key for Africa to engage with the international offset mechanisms and open the door to soil carbon sequestration projects.  相似文献   
110.
Associative learning of host-associated chemical cues was studied in Nasonia vitripennis, a parasitoid of fly pupae in nests of hole-nesting birds. When females encountered a fly pupa and performed one sequence of host recognition behaviour including drilling the ovipositor into the host in the presence of the artificial odour furfurylheptanoate (FFH), they were afterwards arrested by FFH in olfactometer experiments. The response vanished after 4 days and could be blocked after 3 days by feeding wasps with ethacrynic acid prior and after the training. This indicates the formation of an intermediate form of memory by one host experience in N. vitripennis. Interestingly, the trained wasps avoided odours that were not present during the host encounter, although naive wasps did not react to these odours. This unique behaviour probably causes wasps to focus during host searching on those chemical cues they have experienced in the host environment. Studies in nests of hole-nesting birds revealed that about 30% of all nests contained only one fly pupa, and laboratory studies showed that N. vitripennis females are able to parasitise around 100 fly pupae in their life. It is discussed that under these conditions, the formation of a non-permanent intermediate memory for host-associated odours after one host encounter is adaptive to avoid costs involved with formation and maintenance of memory for misleading cues. The demonstration of associative olfactory learning in N. vitripennis, the first parasitoid species with sequenced genome, opens the gate to study molecular mechanisms of memory formation and its ecological adaptation in parasitoids.  相似文献   
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