Hydrocarbons in particulate samples from wildfire events in central Portugal in summer 2010

In summer 2010, twenty eight(14 PM_(2.5)samples plus 14 samples PM_(2.5–10)) smoke samples were collected during wildfires that occurred in central Portugal. A portable high-volume sampler was used to perform the sampling, on quartz fibre filters of coarse(PM_(2.5–10)) and fine(PM_(2.5)) smoke samples. The carbonaceous content(elemental and organic carbon) of particulate matter was analysed by a thermal–optical technique. Subsequently, the particulate samples were solvent extracted and fractionated by vacuum flash chromatography into three different classes of organic compounds(aliphatics, polycyclic aromatic hydrocarbons(PAHs) and carbonyl compounds). The organic speciation was performed by gas chromatography–mass spectrometry(GC–MS). Emissions were dominated by the fine particles, which represented around 92% of the PM_(10). A clear predominance of carbonaceous constituents was observed, with organic to elemental carbon(OC/EC)ratios ranging between 1.69 and 245 in both size fractions. The isoprenoid ketone6,10,14-trimethyl-2-pentadecanone, a tracer for secondary organic aerosol formation, was one of the dominant constituents in both fine and coarse particles. Retene was the most abundant compound in all samples. Good correlations were obtained between OC and both aliphatic and PAH compounds. Pyrogenic processes, thermal release of biogenic compounds and secondary processing accounted for 97% of the apportioned PM_(2.5)levels.     

An optimized two-step derivatization method for analyzing diethylene glycol ozonation products using gas chromatography and mass spectrometry

The ozonation of hydroxyl compounds(e.g., sugars and alcohols) gives a broad range of products such as alcohols, aldehydes, ketones, and carboxylic acids. This study developed and optimized a two-step derivatization procedure for analyzing polar products of aldehydes and carboxylic acids from the ozonation of diethylene glycol(DEG) in a non-aqueous environment using gas chromatography–mass spectrometry. Experiments based on Central Composite Design with response surface methodology were carried out to evaluate the effects of derivatization variables and their interactions on the analysis. The most desirable derivatization conditions were reported, i.e., oximation was performed at room temperature overnight with the o-(2,3,4,5,6-pentafluorobenzyl) hydroxyl amine to analyte molar ratio of 6, silylation reaction temperature of 70°C, reaction duration of 70 min, and N,O-bis(trimethylsilyl)-trifluoroacetamide volume of 12.5 μL. The applicability of this optimized procedure was verified by analyzing DEG ozonation products in an ultrafine condensation particle counter simulation system.     

1980—2014年中亚地区植被净初级生产力对气候和CO2变化的响应

中亚干旱区分布着世界80%以上的温带荒漠,受气候变化影响显著。论文首先收集实验观测数据验证了干旱区生态系统模型（AEM）,然后运用AEM开展数值模拟实验量化研究了1980—2014年中亚净初级生产力（NPP）的时空格局,评估了不同环境因子（降水、温度、CO₂）的相对贡献率及其交互效应。结果表明：过去35 a中亚干旱区年均NPP总量为1 125±129 Tg C（1 T=10¹²）或218±25 g C/m²。哈萨克斯坦北部地区年NPP值较高（349±39 g C/m²）,而南疆地区年NPP值较低（123±45 g C/m²）。1980—2014年间,中亚NPP总体呈减少趋势 [-0.71 g C/(m²·a)],南疆极端干旱区的NPP降低最为显著 [-2.05 g C/(m²·a)]。相较于1980—1984年NPP均值,在1985—2014年中亚区域NPP总体降低了118 Tg（-10%）。其中CO₂施肥效应促进NPP增加了99.7 Tg （+8%）,气温升高的正效应促进NPP增加了35.4 Tg（+2%）,而降水减少导致NPP降低了221 Tg（-18%）。研究区内9%的地区的NPP主要控制因子为温度,主要分布在天山和哈萨克斯坦北部等高纬高寒地区。降水主控区面积占整个研究区的69%,主要分布在荒漠平原特别是南疆等植被受水分限制的区域。CO₂主控区占研究区面积的20%,主要分布在天山中山带森林区和低海拔地区等水热条件好的区域。研究表明新疆南部地区是中亚的关键生态脆弱区,其生态安全面临着气候变化的挑战,但21世纪的升温不大可能因刺激自养呼吸而对中亚区域NPP造成显著影响。     

基于夜间灯光的城市居民直接碳排放及影响因素——以中原经济区为例

城市居民直接能源消耗及其碳排放对区域碳减排政策的制定具有重要影响。受统计数据缺乏与研究方法的限制,当前的研究不仅较少探讨精细空间尺度上的城市居民直接碳排放,同时也缺乏在县级尺度上对人均居民直接碳排放的影响因素进行深入分析。鉴于此,论文以中原经济区为例,通过引入夜间灯光数据,利用增强型饱和校正模型估算了网格尺度上的城市居民碳排放,并采用地理加权回归模型对其影响因素进行了分析。主要研究发现：中原经济区的碳排放总体空间特征是西北高、东南低。郑州市市辖区的城市居民直接碳排放总量位于首位,而邢台县、辉县市和襄垣县的人均碳排放较高。此外,就其影响因素来看,人均GDP、碳排放强度、第二产业比重和HDD（Heating Degree Days,热度日）均表现为正效应,城镇化率为负效应,而CDD（Cooling Degree Days,冷度日）的系数有正有负。城市居民直接碳排放的影响因素分析为中原经济区制定切实可行的区域碳排放政策提供了重要的基础理论依据。     

How does the operational environment affect utility performance? A parametric study on the waste sector

The urban waste treatment service has been a sensitive issue for the Portuguese governments in the past decades. Among other measures, the environmental and economical issues led to the creation of a sector-specific regulator for the waste sector. Considering this atypical circumstance in the worldwide context it is worth studying the external factors that may influence the waste utilities efficiency along with the regulation role. In this regard, we applied the parametric approach of the stochastic frontier analysis to evaluate the influence of the operational environment on the urban waste services performance. The sample included 32 utilities responsible for the waste treatment service in Portugal. The results showed a negative influence of factors, such as the existence of regulation, the distance to the waste treatment facilities and the provision of other services on utility performance. We also observed some benefits from privatisation and incineration, although these options have some particular features.     

Sources and Delivery of Nutrients to the Northwestern Gulf of Mexico from Streams in the South‐Central United States1

Rebich, Richard A., Natalie A. Houston, Scott V. Mize, Daniel K. Pearson, Patricia B. Ging, and C. Evan Hornig, 2011. Sources and Delivery of Nutrients to the Northwestern Gulf of Mexico From Streams in the South‐Central United States. Journal of the American Water Resources Association (JAWRA) 47(5):1061‐1086. DOI: 10.1111/j.1752‐1688.2011.00583.x Abstract: SPAtially Referenced Regressions On Watershed attributes (SPARROW) models were developed to estimate nutrient inputs [total nitrogen (TN) and total phosphorus (TP)] to the northwestern part of the Gulf of Mexico from streams in the South‐Central United States (U.S.). This area included drainages of the Lower Mississippi, Arkansas‐White‐Red, and Texas‐Gulf hydrologic regions. The models were standardized to reflect nutrient sources and stream conditions during 2002. Model predictions of nutrient loads (mass per time) and yields (mass per area per time) generally were greatest in streams in the eastern part of the region and along reaches near the Texas and Louisiana shoreline. The Mississippi River and Atchafalaya River watersheds, which drain nearly two‐thirds of the conterminous U.S., delivered the largest nutrient loads to the Gulf of Mexico, as expected. However, the three largest delivered TN yields were from the Trinity River/Galveston Bay, Calcasieu River, and Aransas River watersheds, while the three largest delivered TP yields were from the Calcasieu River, Mermentau River, and Trinity River/Galveston Bay watersheds. Model output indicated that the three largest sources of nitrogen from the region were atmospheric deposition (42%), commercial fertilizer (20%), and livestock manure (unconfined, 17%). The three largest sources of phosphorus were commercial fertilizer (28%), urban runoff (23%), and livestock manure (confined and unconfined, 23%).     

Where artisanal mines and forest meet: Socio‐economic and environmental impacts in the Congo Basin

While mineral exploitation can provide significant income and employment, it may negatively impact the environment, being ultimately detrimental to livelihoods in the long term. The consequences of mining are of concern in high value forest ecosystems such as the Sangha Tri‐National (TNS) landscape covering Cameroon, the Central African Republic and Republic of the Congo. This paper captures the socio‐economic and environmental impacts of small‐scale mining in the TNS. Using structured questionnaires, consultations and observation, diamonds and gold were found to contribute directly to the livelihoods of at least 5% of the landscape's population. Although up to eight income‐generating strategies are used, mining contributes on average to 65% of total income and is used mainly to meet basic needs. A gold miner's average income is US$ 3.10 a day, and a diamond miner earns US$ 3.08, making them slightly wealthier than an average Cameroonian and three times wealthier than an average non‐miner in the TNS. Environmental impacts were temporary, low impact and of limited scale. However, with mining likely to increase in the near future, an increasing population and miners' low environmental awareness, measures are needed to ensure and reinforce the positive impact of artisanal mining on livelihoods and maintain its low environmental footprint in the TNS landscape.     

基于区域化过程的边缘地区发展模式——以南阳市为例

边缘地区的发展问题一直是区域研究中的重点和难点，研究其发展轨迹、机理对于促进经济相对滞后的边缘区域发展具有重要意义。以豫鄂两省交界地区的南阳地区为例，在实地调研基础上，对其处于“核心→边缘”中的区域化过程进行阐述，采用区位商和“三轴图”产业重心方〖JP2〗法对其边缘化过程进行分析，针对南阳地区实际发展状况，提出未来解决边缘化的主要发展模式：（1）“CI”区域形象设计，推行区域形象发展模式；（2）“特色农产品＋农户＋中介＋（市场）明星企业”的农业产业化模式、“特色资源+生态工业园”的工业发展模式；（3）以旅游和物流为主的交通驱动型第三产业发展模式，通过特色模式带动地区经济快速高效发展，以期为南阳地区及同类区域发展提供有益建议。     

全球变暖背景下中亚兴都库什、喀喇昆仑及天山气候变化研究进展

中亚兴都库什、喀喇昆仑及天山山脉（HKT）是气候变化敏感区,其在全球变暖背景下的气候变化对区域生态和经济系统的稳定性及可持续发展有重要意义。目前对中亚高海拔地区的研究多集中于局部区域,有关HKT地区气候变化的综合对比分析较为缺乏。本文对HKT地区现代气候变化的相关研究成果进行简单梳理和回顾,重点总结了HKT地区气候变化特征、影响机制及其与全球变暖的联系。结果表明：（1）近60 a,HKT地区不同区域气候的时空特征存在差异,从时间上看,天山的年均温及年降水量均呈上升趋势,而兴都库什-喀喇昆仑山的年均温呈不显著增加趋势,其年降水量变化趋势不稳定;从空间上看,HKT地区山脉南坡气温高于北坡,但北坡降水量高于南坡,且天山南北坡年降水均呈上升趋势。（2）HKT地区的气候变化除了受西风环流、南亚印度季风及局地条件等影响外,还受到北大西洋涛动和厄尔尼诺-南方涛动等大尺度气候模态的调制,如兴都库什-喀喇昆仑山脉在NAO正（负）位相和ENSO暖（冷）位相降水趋于增加（减少）。