一台气相色谱仪同时测定陆地生态系统CO2、CH4和N2O排放

通过对气相色谱仪进样、分析气路和阀驱动系统的改造 ,同一台色谱仪可以同时检测空气样品中的CO2 、CH4和N2 O。测试结果表明 ,仪器的灵敏度、分辨率和精密度均很高 ,线性范围符合要求 ;仪器系统能够在野外实验室长期稳定运转 ,可方便用于测定陆地生态系统CO2 、CH4和N2 O排放 ,能快速、准确、可靠地获取观测数据。     

施用化肥对农业生态环境的负面影响及对策

论述了肥料的过量使用对我国的农业生态环境质量的负面影响，提出了合理施用化肥防治环境污染的对策。认为过量施用化肥引起土壤酸化和板结、重金属污染、硝酸盐污染和土壤次生盐渍化，从而导致土壤肥力下降，并且造成水体富营养化，淋溶污染地下水，致使作物品质下降，硝酸盐含量超标，并通过食物链危害人体健康。此外，认为化肥对大气环境的影响主要集中在氮肥上，氨挥发和NOx、CH4及CO2的释放，不仅能引起温室效应，而且还能够引起臭氧层的破坏。提出了相应的对策：增加科技教育的投入，提高农民的科学文化素质，提高全民的环境意识；合理施肥；结合国家的调控政策，在粮食产量与环境保护、作物产量与产品品质之间找到平衡点。     

长江经济带农业源非二氧化碳温室气体排放的时空特征

利用清单方法核算了1980~2016年长江经济带农业源非二氧化碳（CO₂）温室气体的排放总量和排放强度,分析了不同经济发展情景和农业-环境脱钩状态下长江经济带2030年和2050年的排放情景.研究表明：时间维度上,1980~2016年长江经济带农业源非CO₂温室气体排放总量呈上升趋势,从0.26Gt CO₂-eq上升到0.32Gt CO₂-eq;2030年和2050年在高情景和中情景2种情景下,长江经济带农业源非CO₂温室气体排放量不会达峰,江苏、湖南、重庆、云南、湖北和安徽等六省（市）的单位农地面积排放强度将增加;3种情景下,四川始终为单位农地面积排放强度较低的地区.     

三维荧光与平行因子研究黑臭河流DOM

利用三维荧光光谱（EEMs）与平行因子（PARAFAC）模型相结合,分析了沈阳市5条典型黑臭水体溶解性有机物（DOM）的荧光组分特征,并结合常规水质指标,利用主成分分析法（PCA）对影响黑臭水体DOM的主要因素及其贡献量进行了研究.结果表明,沈阳市典型黑臭水体DOM主要由类蛋白荧光组分C1（235,360）,类富里酸荧光组分C2（220,430）和类腐殖酸荧光组分C3（255,520）组成.C2类富里酸物质与COD_Cr、氨氮、S^2-、TP有很强的正相关性,与DO和透明度成负相关,来自于陆源;C1类色氨酸和C3类腐殖酸表现出明显的正相关,具有同源性,来自于微生物內源.陆源有机质组分对黑臭水体DOM的贡献率高达61.2%,微生物内源组分对黑臭水体DOM的贡献率为25.5%.5个黑臭水体在水质上存在差异,支流Ⅰ和支流Ⅱ为重度黑臭,支流Ⅲ、Ⅳ和Ⅴ为轻度黑臭.     

生物质炭与有机物料混施对土壤温室气体排放和微生物活性的影响

土壤是温室气体的重要排放源,在土壤中施入生物质炭和有机物料对土壤微生物在土壤碳氮转化和微量气体代谢方面有着重要作用,不过迄今在生物质炭和有机物料混施对土壤温室气体排放和微生物活性的影响方面的研究尚少.本研究采用室内培养试验,利用土壤添加生物质炭和生物质炭与不同有机物料混施,探究生物质炭和有机物料混施对土壤温室气体排放及微生物活性的影响.共设5个处理:新鲜土壤(S)、新鲜土壤+2%生物质炭(SB)、新鲜土壤+2%生物质炭+1%大豆饼(SBS)、新鲜土壤+2%生物质炭+1%小麦秸秆(SBW)、新鲜土壤+2%生物质炭+1%鸡粪(SBC).研究表明:只添加生物质炭对温室气体的排放影响不明显;生物质炭与有机物料混施使土壤的CO2、N2O排放明显增加,而对CH4的排放影响不明显;从温室气体增温潜势(GWP)变化可以看出有机物料施用对温室效应具有明显的增强作用;生物质炭与有机物料混施在一定程度上增加微生物生物量碳和代谢熵(q CO2),各处理的代谢熵是对照处理S的0.18~4.37倍;不同有机物料对FDA水解酶、过氧化氢酶、脲酶和碱性磷酸酶活性都表现为激活作用.     

Large inter annual variation in air quality during the annual festival ‘Diwali' in an Indian megacity

A network of air quality and weather monitoring stations was established under the System of Air Quality Forecasting and Research(SAFAR) project in Delhi. We report observations of ozone(O_3), nitrogen oxides(NO_x), carbon monoxide(CO) and particulate matter(PM_2.5and PM_(10)) before, during and after the Diwali in two consecutive years, i.e., November 2010 and October 2011. The Diwali days are characterised by large firework displays throughout India. The observations show that the background concentrations of particulate matter are between 5 and 10 times the permissible limits in Europe and the United States. During the Diwali-2010, the highest observed PM_(10) and PM_2.5mass concentration is as high as2070 μg/m~3 and 1620 μg/m3, respectively(24 hr mean), which was about 20 and 27 times to National Ambient Air Quality Standards(NAAQS). For Diwali-2011, the increase in PM_(10) and PM_2.5mass concentrations was much less with their peaks of 600 and of 390 μg/m~3 respectively, as compared to the background concentrations. Contrary to previous reports,firework display was not found to strongly influence the NO_x, and O_3 mixing ratios, with the increase within the observed variability in the background. CO mixing ratios showed an increase. We show that the large difference in 2010 and 2011 pollutant concentrations is controlled by weather parameters.     

Quantifying methane emission from fugitive sources by combining tracer release and downwind measurements – A sensitivity analysis based on multiple field surveys

Using a dual species methane/acetylene instrument based on cavity ring down spectroscopy (CRDS), the dynamic plume tracer dispersion method for quantifying the emission rate of methane was successfully tested in four measurement campaigns: (1) controlled methane and trace gas release with different trace gas configurations, (2) landfill with unknown emission source locations, (3) landfill with closely located emission sources, and (4) comparing with an Fourier transform infrared spectroscopy (FTIR) instrument using multiple trace gasses for source separation. The new real-time, high precision instrument can measure methane plumes more than 1.2 km away from small sources (about 5 kg h^?1) in urban areas with a measurement frequency allowing plume crossing at normal driving speed. The method can be used for quantification of total methane emissions from diffuse area sources down to 1 kg per hour and can be used to quantify individual sources with the right choice of wind direction and road distance. The placement of the trace gas is important for obtaining correct quantification and uncertainty of up to 36% can be incurred when the trace gas is not co-located with the methane source. Measurements made at greater distances are less sensitive to errors in trace gas placement and model calculations showed an uncertainty of less than 5% in both urban and open-country for placing the trace gas 100 m from the source, when measurements were done more than 3 km away. Using the ratio of the integrated plume concentrations of tracer gas and methane gives the most reliable results for measurements at various distances to the source, compared to the ratio of the highest concentration in the plume, the direct concentration ratio and using a Gaussian plume model. Under suitable weather and road conditions, the CRDS system can quantify the emission from different sources located close to each other using only one kind of trace gas due to the high time resolution, while the FTIR system can measure multiple trace gasses but with a lower time resolution.     

Cost estimates of the Kigali Amendment to phase-down hydrofluorocarbons

Hydrofluorocarbons (HFCs) are synthetically produced compounds primarily used for cooling purposes and with strong global warming properties. In this paper, we analyze the global abatement costs for achieving the substantial reductions in HFC consumption agreed in the Kigali Amendment (KA) of the Montreal Protocol from October 2016. We estimate that compliance with the KA is expected to remove 39 Pg CO₂eq or 61% of global baseline HFC emissions over the entire period 2018–2050. The marginal cost of meeting the KA targets is expected to remain below 60 €/t CO₂eq throughout the period in all world regions except for developed regions where legislation to control HFC emissions has already been in place since a few years. For the latter regions, the required HFC consumption reduction is expected to come at a marginal cost increasing steadily to between 90 and 118 €/t CO₂eq in 2050. Depending on the expected rate of technological development and the extent to which envisaged electricity savings can be realized, compliance with KA is estimated attainable at a global cost ranging from a net cost-saving of 240 billion € to a net cost of 350 billion € over the entire period 2018 to 2050 and with future global electricity-savings estimated at between 0.2% and 0.7% of expected future electricity consumption.     

常压下煤对N2/CO2/CH4单组分气体吸附特性研究

为了研究常压不同条件下煤样对N2/CO2/CH4单组分气体的吸附特性,以Langumir单分子层吸附模型为依据,对其吸附阶段进行划分,选择长焰煤、气肥煤和无烟煤分别进行了单组分气体吸附试验,探讨不同试验条件对煤吸附量的影响。结果表明:在常压阶段,煤对单组分气体的吸附规律服从Langumir单分子层吸附模型的第一阶段,吸附量与压力正相关;煤的变质程度、吸附温度及压力和吸附气体的种类是影响吸附量的主要因素,并在不同情况下对煤吸附量的影响程度不同;高低变质煤样对吸附量的影响大,而中等变质程度的影响小;温度是低压阶段影响吸附量的主要因素;吸附气体种类对吸附量的影响是由于其自身物化性质差异,相同试验条件下煤对3种单组分气体的吸附量从大到小为CO2、CH4、N2。     

咸阳市温室气体排放的动态分析及等级评估

通过采用《2006年IPCC国家温室气体清单指南》和中国《省级温室气体编制指南》推荐的方法,分析了咸阳市温室气体排放的动态变化,并提出基于全球标准的温室气体排放等级评价方法,对咸阳市温室气体进行了排放等级评估.结果表明:1995—2011年,咸阳市温室气体排放量从1253.21×104t上升为5531.06×104t,年均增高9.72%,呈快速上升趋势.工业(年均增高21.34%)为增幅最高的部门,其次依次为能源(9.62%)、废弃物(7.90%)、农业(2.45%).从温室气体构成看,能源占84.73%~91.81%,工业占1.46%~8.55%,农业占3.11%~9.32%,林业碳减排占-0.53%~-2.36%,废弃物处理占1.31%~8.39%.由此可见,咸阳市温室气体排放增长的主要原因是能源消费的增加以及工业生产的大幅增长.万元GDP温室气体排放量波动下降,年均降低4.53%;人均、单位面积温室气体排放量和温室气体排放指数快速升高,年均增幅分别达9.31%、9.72%和9.48%.16年间,咸阳市温室气体排放等级从较低(Ⅰc)持续升高至中上等级(Ⅱc),已高出应对全球气候变暖目标(Ⅰb)4个亚级,温室气体减排工作刻不容缓.