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981.
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
982.
Ye Cheng Chenglong Zhang Yuanyuan Zhang Hongxing Zhang Xu Sun Yujing Mu 《环境科学学报(英文版)》2015,28(2):163-170
Atmospheric mixing ratios of carbonyl sulfide(COS) in Beijing were intensively measured from March 2011 to June 2013. COS mixing ratios exhibited distinct seasonal variation, with a maximum average value of 849 ± 477 pptv in winter and a minimal value of 372 ± 115 pptv in summer. The seasonal variation of COS was mainly ascribed to the combined effects of vegetation uptake and anthropogenic emissions. Two types of significant linear correlations(R2 0.66) were found between COS and CO during the periods from May to June and from October to March, with slopes(ΔCOS/ΔCO) of 0.72 and 0.14 pptv/ppbv, respectively. Based on the emission ratios of COS/CO from various sources, the dominant anthropogenic sources of COS in Beijing were found to be vehicle tire wear in summer and coal burning in winter. The total anthropogenic emission of COS in Beijing was roughly estimated as 0.53 ± 0.02 Gg/year based on the local CO emission inventory and the ΔCOS/ΔCO ratios. 相似文献
983.
本文运用对数平均的LMDI 分解模型,选取工业SO2、工业烟(粉)尘排放量作为污染物指标,将2006—2013 年,乌鲁木齐工业废气排放量影响因素分解为规模效应、结构效应、技术效应,考虑到技术效应机制的复杂性,进一步将技术效应细化为污染治理效应和清洁技术效应。研究结果表明:规模效应和结构效应增加乌鲁木齐工业废气排放,其中规模效应对工业废气排放量贡献率由2007 年的119.10%增加到2013 年的263.03%,结构效应对工业废气排放量的增加也起到一定的促进作用,但影响效果远低于规模效应,年贡献率均低于10%,技术效应阻碍工业废气排放的增加,贡献率由2007 年的-19.86%增加到2013 年的-172.50%。制造业和电力、燃气及水的生产和供应业废气排放量占工业废气排放总量的70% 左右,是乌鲁木齐工业废气污染的主要行业。清洁技术效应对SO2 的减排起促进作用,是阻碍工业SO2 排放量增加的主要因素。污染治理效应是工业烟(粉)尘的减排主要因素,说明目前乌鲁木齐工业烟(粉)尘的减排依赖于排放后的治理。 相似文献
984.
Nicolas A.O. Morin Patrik L. Andersson Sarah E. Hale Hans Peter H. Arp 《环境科学学报(英文版)》2017,29(12):115-132
Flame retardants in commercial products eventually make their way into the waste stream.Herein the presence of flame retardants in Norwegian landfills, incineration facilities and recycling sorting/defragmenting facilities is investigated. These facilities handled waste electrical and electronic equipment(WEEE), vehicles, digestate, glass, combustibles, bottom ash and fly ash. The flame retardants considered included polybrominated diphenyl ethers(∑BDE-10) as well as dechlorane plus, polybrominated biphenyls, hexabromobenzene,pentabromotoluene and pentabromoethylbenzene(collectively referred to as ∑FR-7). Plastic,WEEE and vehicles contained the largest amount of flame retardants(∑BDE-10: 45,000–210,000 μg/kg; ∑FR-7: 300–13,000 μg/kg). It was hypothesized leachate and air concentrations from facilities that sort/defragment WEEE and vehicles would be the highest. This was supported for total air phase concentrations(∑BDE-10: 9000–195,000 pg/m~3 WEEE/vehicle facilities, 80–900 pg/m~3 in incineration/sorting and landfill sites), but not for water leachate concentrations(e.g., ∑BDE-10: 15–3500 ng/L in WEEE/Vehicle facilities and 1–250 ng/L in landfill sites). Landfill leachate exhibited similar concentrations as WEEE/vehicle sorting and defragmenting facility leachate. To better account for concentrations in leachates at the different facilities, waste-water partitioning coefficients, Kwastewere measured(for the first time to our knowledge for flame retardants). WEEE and plastic waste had elevated Kwastecompared to other wastes, likely because flame retardants are directly added to these materials. The results of this study have implications for the development of strategies to reduce exposure and environmental emissions of flame retardants in waste and recycled products through improved waste management practices. 相似文献
985.
西北地区雾霾风沙较大,环境保护形势严峻,在搭建西北地区物流网络过程中,要尽量降低物流排放,缩短物流路径,提高环境保护效果.提出一种物流资源属性组合配置的西北地区物流网络搭建模型,分析物流网络搭建与环境保护的关系,从静态属性和动态属性两部分出发进行物流网络搭建和网络拓扑控制,采用前向树状拓扑控制协议进行物流资源属性优化组合配置,降低物流资源损耗和污染物质排放量,实现节能减排,促进环境保护机制的有效形成.研究表明,通过对西北地区物流网络优化搭建,物流链路中的碳排放得到有效降低,提高了环境保护的效能. 相似文献
986.
基于台架测试的我国船用柴油机废气排放因子 总被引:2,自引:1,他引:1
基于燃油消耗和基于船舶活动两种方法准确测算我国水路运输行业的废气排放量,对我国生产的分别满足国际海事组织(International Maritime Organization,IMO)NO_xTierⅠ、TierⅡ标准的76台和113台船用柴油机母型机排放测试报告进行了统计分析,研究确定了二冲程主机、四冲程主机和四冲程副机NO_x、CO、HC和CO_2基于燃油的排放因子和基于做功的排放因子.结果表明,不同类型柴油机NO_x、CO、HC和CO_2基于燃油的排放因子分别为30.67~76.55、3.01~6.13、1.25~2.24和3 141.15~3 165.63 kg·t~(-1);不同类型柴油机NO_x、CO、HC和CO_2基于做功的排放因子分别为6.83~13.64、0.61~1.35、0.21~0.50和534.04~745.18 g·(k W·h)~(-1).不同类型柴油机基于做功的排放因子与柴油机负荷密切相关,并可用幂函数或二次多项式来表达其关系;另外,通过对国外机构采用的排放因子进行简单的修正难以真实反映我国船用柴油机排放技术水平.相关研究结果为我国船舶排放清单的测算提供了具有适用性的基础数据. 相似文献
987.
Support for the notion that policy should embrace sustainability is widespread but the actual incorporation of the concept into policy is proving to be difficult. To insert the word into a policy document, accompanied by some marginal changes, is enough to allow policy makers to claim that sustainability has been considered. The novel research reported here has applied sustainability analysis to the case of aviation which is one of the areas of policy where the conflict between environmental and economic objectives is most intense. It was found that sustainable policy options are blocked whilst sustainability is regarded as an add-on to existing policy. The policy stalemate exists because it is neither understood nor accepted that sustainability requires systemic change. The empirical stage of the research comprised 28 stakeholder interviews and identified four categories of action with the potential to break the stalemate in aviation which could be applied also to other areas of policy: long-term strategic planning; facilitation of dialogue between stakeholders; government support for innovation; and educating the public. The study concluded that fundamental change to the process of crafting policy is required if sustainability is to fulfil its potential to reconcile environmental and economic objectives. 相似文献
988.
旅游活动低碳化是新时期旅游业发展及其应对气候变化行动的根本需求。旅游活动碳核算作为低碳旅游研究的核心基础,旨在通过量化分析旅游活动的相关碳排放以准确评价其对气候变化的影响,进而为低碳旅游建设提供决策和数据支持。采用文献归纳及对比分析等方法,对过去一段时期的旅游碳排放及低碳旅游研究做了全面综述,发现当前旅游碳核算多基于公式模型模拟估算和滞后的公开数据,在测算过程中受边界模糊、数据获取困难、模型普适性差等因素影响,核算结果存在不确定性且不具备可比性。同时,不同主体低碳旅游内涵的差异导致对核算结果的需求不同,与实践寻求存在脱节。因此,未来亟需建立统一的旅游行业碳核算规范与标准体系,确定旅游碳排放核算方法及其基线,拓展低碳旅游研究深度及广度,开展低碳旅游科学示范点建设,重视政策制定实践性方面的研究。 相似文献
989.
Richard L. Ottinger 《Natural resources forum》2006,30(4):318-327
The imperatives for reducing the world's dependence on fossil and nuclear fuels have multiplied manifold in recent years with the advent of worldwide terrorism. These new dangers come in addition to the imperatives of addressing the dire consequences of global warming and devastating pollution that accompany the use of these fossil fuels. Reducing dependence on these unsafe and unreliable energy resources should be a top global priority. Implementation of proven energy efficiency technologies offers the world the fastest, safest, most economic and most environmentally benign way to alleviate these threats. This article outlines available efficiency measures, their economic advantages and means by which they may be and have been implemented. While examples of efficiency applications from both developed and developing countries are given, the article relies heavily on experience with energy efficiency in the United States, where data on efficiency is particularly abundant. 相似文献
990.
Importance of Sulfate Aerosol in Evaluating the Relative Contributions of Regional Emissions to the Historical Global Temperature Change 总被引:3,自引:0,他引:3
Andronova Natalia Schlesinger Michael 《Mitigation and Adaptation Strategies for Global Change》2004,9(4):383-390
During the negotiations of the KyotoProtocol the delegation of Brazil presentedan approach for distributing the burden ofemissions reductions among the Partiesbased on the effect of their cumulativehistorical emissions on the global-averagenear-surface temperature. The Letter tothe Parties does not limit the emissions tobe considered to be only greenhouse gas(GHG) emissions. Thus, in this paper weexplore the importance of anthropogenicSOx emissions that are converted tosulfate aerosol in the atmosphere, togetherwith the cumulative greenhouse gasemissions, in attributing historicaltemperature change. We use historicalemissions and our simple climate model toestimate the relative contributions toglobal warming of the regional emissions byfour Parties: OECD90, Africa and LatinAmerica, Asia, and Eastern Europe and theFormer Soviet Union. Our results show thatfor most Parties the large warmingcontributed by their GHG emissions islargely offset by the correspondingly largecooling by their SOx emissions. Thus,OECD90 has become the dominant contributorto recent global warming following itslarge reduction in SOx emissions after1980. 相似文献