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351.
Surface water methane (CH4) and nitrous oxide (N2O) concentrations and fluxes were investigated in two subtropical coastal embayments (Bramble Bay and Deception Bay, which are part of the greater Moreton Bay, Australia). Measurements were done at 23 stations in seven campaigns covering different seasons during 2010–2012. Water–air fluxes were estimated using the Thin Boundary Layer approach with a combination of wind and currents-based models for the estimation of the gas transfer velocities. The two bays were strong sources of both CH4 and N2O with no significant differences in the degree of saturation of both gases between them during all measurement campaigns. Both CH4 and N2O concentrations had strong temporal but minimal spatial variability in both bays. During the seven seasons, CH4 varied between 500% and 4000% saturation while N2O varied between 128 and 255% in the two bays. Average seasonal CH4 fluxes for the two bays varied between 0.5 ± 0.2 and 6.0 ± 1.5 mg CH4/(m2·day) while N2O varied between 0.4 ± 0.1 and 1.6 ± 0.6 mg N2O/(m2·day). Weighted emissions (t CO2-e) were 63%–90% N2O dominated implying that a reduction in N2O inputs and/or nitrogen availability in the bays may significantly reduce the bays' greenhouse gas (GHG) budget. Emissions data for tropical and subtropical systems is still scarce. This work found subtropical bays to be significant aquatic sources of both CH4 and N2O and puts the estimated fluxes into the global context with measurements done from other climatic regions.  相似文献   
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In this paper the contingent valuation method (CVM) is applied to public risk reduction. Theory suggests that the size of the stated willingness to pay (WTP) for risk reduction depends on private activities aimed at reducing the risk level for the individual. The empirical results suggest that considering private averting activities increases the explanatory power of the estimated WTP function significantly. Thus, WTP passes the scope test which proposes that larger reductions from a larger baseline risk should be valued higher than lower risk reductions from a lower baseline risk. Furthermore, we demonstrate that the follow-up response format induces anchoring effects.  相似文献   
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The influence of explosive wastes in soil on the reproduction of the springtailFolsomia candida (Willem 1902) (insects of the Order Collembola) was investigated in a standard test according to ISO-Draft-Guideline 11268-2. In the test, we used soils with 3 different contamination levels from an area used for different military purposes (in Hallschlag, Germany), especially for explosive operations, since the beginning of the century. We found different and heterogenous mixtures of contaminants in the soils (primarily TNT and DNT) which resulted in a high mortality rate among the adult insects and in a dramatic reduction in the reproductive potential of the Collembola. In the mixture of contaminants with the highest contamination levels, the total extinction of exposed Collembola was observed as a result of the death of adult insects.  相似文献   
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The basis for the first energy and flow analysis of the University of Osnabrück and the resulting ecobalance was an extensive data collection, preparation and processing. To simplify drawing up the balance in the following years and to facilitate an eco-controlling based on this data, a concept for a University’s Environmental Information System (EIS) was developed. It consists of three parts: the operative level includes the data bases of the individual administrative departments; at the central data base level, the ecobalance and the environmental characteristic values are computed; and the processing and presentational level serves as an interface between the data and users. The implementation of the EIS is intended within the framework of the general Management Information System, the development of which was started in 1998.  相似文献   
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