Modeling of the long-term tropospheric trends of hydroxyl radical for the Northern Hemisphere

The MGO 2D (altitude–longitude) channel photochemical transport model has been applied to elucidate the spatial and temporal behavior of the hydroxyl radical in the troposphere of the northern temperate belt for the pre-industrial (1850) period and the last few decades (1960 and 1995). The relation between the tropospheric OH content and the carbon monoxide, methane, nitrogen oxides emissions during 1850–1995 is studied. The distribution of the carbon monoxide concentration is calculated and validated using the observational data collected in the different locations because of the geographical non-homogeneity of its emissions. The response of the hydroxyl radical concentrations to the non-homogeneity of the CO and other atmospheric species distribution is estimated. The carbon monoxide and methane contributions to the hydroxyl photochemical sink are also evaluated. Because the changes of OH in the troposphere alternate the intensity of methane and carbon monoxide oxidation, the CO, CH₄ and OH lifetime evolution due to the increase of anthropogenic pollution intensity is analyzed and discussed.     

Carbon materials-catalyzed hydroliquefaction of flame-retardant plastics in organic solvents

Flame-retardant plastics, such as desktop and laptop personal computer bodies, could be completely liquefied by carbon materials-catalyzed hydroliquefaction in tetralin without using H₂ as a hydrogen source. Active carbons with larger surface areas (1450–3450 m²/g) acted as superior catalysts in transferring tetralin hydrogens to plastics. On the other hand, carbon blacks and fullerene-rich soot were less active catalysts. Graphite and mesocarbon microbeads did not show any catalytic effects. Benzene, toluene, and ethylbenzene were obtained as recyclable hydrocarbons; their total amounts varied from 4 wt% to 12 wt% depending on the types of plastics and the carbon materials used. Organic bromides such as polybromodioxins were not contained in the gases and oils of the product. Received: July 19, 2000 / Accepted: September 17, 2000     

基于生态足迹方法的中国生态可持续性分析

基于生态足迹和EMD方法,分析了中国1961~2005年生态可持续性的周期性变化,并建立具有周期性波动的非线性动力学模型,预测未来10年中国人均生态足迹和生物承载力的发展趋势。结果发现:44年来,中国人均生态足迹具有明显的4.3年、14.3年和17年3个波动周期,人均生物承载力具有明显的3.5年、8.8年、17.7年和44年4个波动周期;若未来10年中国人均生态足迹和生物承载力均延续过去44年的变化趋势,则2015年人均生态足迹、生物承载力、生态赤字将分别为1.366ghm²、1.108ghm²和0.258ghm²,人均生态足迹和生态赤字较2005年分别下降了0.27ghm²、0.441ghm²,而人均生物承载力增加了0.171ghm²。在保持经济、技术和人民生活水平稳步提高的同时,这种程度的生态超载有可能通过贸易引进生物承载力,通过技术进步、提高管理水平等增加生物承载力得到缓解。     

基于EFA的旅游景区生态承载力及可持续发展

生态足迹分析(EFA)是一种测量人类对自然利用程度、量化生态承载力的新方法。为测度旅游景区的建设强度对其开发区域生态承载力的影响,本文提出基于生态足迹的“生态占用率”及划分“生态占用适宜度”的“生态占用黄金分割法”,并以湖北中华山森林公园为实例,定量分析该项目对景区生态承载力的影响及游客规模限量;为旅游业的可持续发展提供了新思路。     

微环境新风量的检测原理及方法研究

新风量是评价室内微环境空气卫生质量的主要卫生指标之一,也是计算室内某种气体单位时间排放量的重要参数。以CO2作为示踪气体,利用于冰升华和人体呼吸产生CO2示踪气体两种测量方法对室内和车内微环境进行了检测,并考虑室内人呼出CO2量的影响,运用箱子模式的各种推导公式（稳态法、解析解法和差分法）对新风量进行了计算,并对结果进行了讨论。结果表明,没有人存在下,用箱子模式的解析解法和差分法计算的新风量值没有明显的统计差异;微环境内有人时必须考虑人释放的影响,这样箱子模式的各种推导公式都可以计算新风量值,且结果准确,准确度高。利用人体呼吸产生CO2示踪气体法,用差分法计算结果不理想,偏差很大;用稳态法计算重现性高,结果可靠。     

添加乙醇碳源对驯化菌种降解油制气废水的影响

进行了添加乙醇作为碳源强化油制气废水生物降解的研究,并利用GC／MS分析对油制气废水中芳烃类化合物的降解进行了初步研究。研究表明,共代谢基质乙醇的加入,可使菌种S-2、Y-3、XH-3、M-3对COD、氨氮、可萃取有机物等指标的去除率分别提高17．6％～25．6％、34．9％～42．8％、10．4％～14．2％;但在所采用的时间范围内,酚类化合物的去除率降低;芳烃类化合物的去除率提高15．4％～21．2％。除了维持无共代谢条件下对芳环数≤3的芳烃类化合物的良好降解能力外,对芳环数为4～6的化合物降解能力也有所提高。     

Composting,anaerobic digestion and biochar production in Ghana. Environmental–economic assessment in the context of voluntary carbon markets

In some areas of Sub-Saharan Africa appropriate organic waste management technology could address development issues such as soil degradation, unemployment and energy scarcity, while at the same time reducing emissions of greenhouse gases. This paper investigates the role that carbon markets could have in facilitating the implementation of composting, anaerobic digestion and biochar production, in the city of Tamale, in the North of Ghana. Through a life cycle assessment of implementation scenarios for low-tech, small scale variants of the above mentioned three technologies, the potential contribution they could give to climate change mitigation was assessed. Furthermore an economic assessment was carried out to study their viability and the impact thereon of accessing carbon markets. It was found that substantial climate benefits can be achieved by avoiding landfilling of organic waste, producing electricity and substituting the use of chemical fertilizer. Biochar production could result in a net carbon sequestration. These technologies were however found not to be economically viable without external subsidies, and access to carbon markets at the considered carbon price of 7 EUR/ton of carbon would not change the situation significantly. Carbon markets could help the realization of the considered composting and anaerobic digestion systems only if the carbon price will rise above 75–84 EUR/t of carbon (respectively for anaerobic digestion and composting). Biochar production could achieve large climate benefits and, if approved as a land based climate mitigation mechanism in carbon markets, it would become economically viable at the lower carbon price of 30 EUR/t of carbon.     

秸秆生物炭对河套灌区膜下滴灌玉米农田生态系统碳足迹的影响

为探究生物炭对干旱地区膜下滴灌玉米农田生态系统温室气体排放和碳足迹的影响.设置不同施用量的生物炭处理［0（CK）、15（C15）、30（C30）和45 t ·hm^-2（C45）］,连续2 a监测覆膜滴灌条件下一次性施用秸秆生物炭后玉米农田生态系统土壤温室气体（CO₂、N₂O和CH₄）排放的季节变化及其综合增温潜势,利用生命周期评估法估算农业生产活动引起的碳排放量,并进行碳足迹的分析.施用生物炭当年的作物生长季土壤CO₂累积排放量比CK下降17.6%~24.7%,N₂O累积排放量下降71.1%~110.4%,综合增温潜势降低19.5%~25.9%.生物炭施用后第2 a作物生长季的CO₂累积排放量比CK减少19.2%~40.6%,N₂O累积排放量减少38.7%~46.7%,综合增温潜势减少19.7%~40.5%.连续2 a处理C15和C30均不同程度增加了CH₄累积吸收量,而处理C45显著降低了CH₄累积吸收量.C15和C45分别为生物炭施用当年和翌年单位产量碳足迹最少的处理,其单位产量碳足迹较CK分别降低10.1%和26.2%.土壤温室气体排放量对玉米农田生态系统碳足迹贡献率最大（38.1%~59.2%）,其次为氮肥生产（19.8%~33.4%）,而后为电能生产（6.7%~8.8%）和地膜覆盖（4.4%~7.4%）.生物炭对生态系统碳足迹贡献率为5.7%~13.8%.施用30 t ·hm^-2生物炭对农田生态系统减排固碳增产效果更好.改善生物炭制作工艺及运输途径、提高氮肥利用效率和发展节水节能灌溉技术,是减少旱区农田生态系统碳足迹的重要途径.     

长春市膳食水足迹研究

食物是居民日常生活首要的消费品,膳食水足迹能反映一个地区对水资源的利用情况。根据长春市2000年一2009年城乡居民膳食消费量,量化长春市城乡居民膳食水足迹,分析其特征。10年来长春市城乡居民膳食水足迹差异在逐渐减小,城镇居民的多样性指数始终高于农村居民,但差值逐渐减小,城乡居民膳食水足迹存在巨大差距,不公平现象很明显。探讨不同膳食消费模式下水资源的节约量,为长春市合理利用水资源提供依据。     

确定大气环境承载力的烟云足迹法

本文讨论了大气承载力的定义,同时也给出了计算大气承载力的烟云足迹法的原理和计算公式,此外还给出了根据区域气象条件计算烟云足迹函数的具体算式和大气环境承载力的计算实例,烟云足迹分析法可为区域间的排污权交易提供技术基础.