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331.
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
332.
B. Henderson A. Falcucci A. Mottet L. Early B. Werner H. Steinfeld P. Gerber 《Mitigation and Adaptation Strategies for Global Change》2017,22(1):199-224
Livestock [inclusive of ruminant species, namely cattle (Bos Taurus and Bos indicus), sheep (Ovis aries), goats (Capra hircus), and buffaloes (Bubalus bubalis), and non-ruminant species, namely pigs (Sus scrofa domesticus) and chickens (Gallus domesticus)] are both affected by climate change and contribute as much as 14.5 % of global anthropogenic greenhouse gas (GHG) emissions, most of which is from ruminant animals (Gerber et al. 2013). This study aims to estimate the marginal costs of reducing GHG emissions for a selection of practices in the ruminant livestock sector (inclusive of the major ruminant species—cattle, sheep, and goats) globally. It advances on previous assessments by calculating marginal costs rather than commonly reported average costs of abatement and can thus provide insights about abatement responses at different carbon prices. We selected the most promising abatement options based on their effectiveness and feasibility. Improved grazing management and legume sowing are the main practices assessed in grazing systems. The urea (CO(NH2)2) treatment of crop straws is the main practice applied in mixed crop–livestock systems, while the feeding of dietary lipids and nitrates are confined to more intensive production systems. These practices were estimated to reduce emissions by up to 379 metric megatons of carbon dioxide (CO2) equivalent emissions per year (MtCO2-eq yr?1). Two thirds of this reduction was estimated to be possible at a carbon price of 20 US dollars per metric ton of CO2 equivalent emissions ($20 tCO2-eq?1). This study also provides strategic guidance as to where abatement efforts could be most cost effectively targeted. For example, improved grazing management was particularly cost effective in Latin America and Sub-Saharan Africa, while legume sowing appeared to work best in Western Europe and Latin America. 相似文献
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Anselm U. Romer Werner W. Pommerehne Lars P. Feld 《Journal of Environmental Planning and Management》1998,41(4):477-503
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
336.
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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B. Kanitscheider J. Schwartzkopff H. O. Hettche O. Kinne B. Werner H. Pick G. Traving E. Lamla P. Ramdohr H. Strunz H. Werner H. Preuß E. Pfeil K. -J. Euler M. Becke G. Wunsch F. Frimmel H. Puchelt L. Horner B. Schenck L. Jaenicke D. Gericke K. Goerttler G. Wagner O. Creutzfeldt W. F. Angermeier H. Jockusch G. Kobabe G. Habermehl J. Jacobs H. Ziegler 《Die Naturwissenschaften》1975,62(1):45-52