Emissions trading in Hong Kong and the Pearl River Delta region—A modeling approach to trade decisions in Hong Kong's electricity industry

In 2002, the Hong Kong government and the Guangdong provincial government agreed to reduce emissions of sulfur dioxide, nitrogen oxides, respirable suspended particulates, and volatile organic compounds by 40%, 20%, 55%, and 55%, respectively. There was strong public demand for the power stations in Hong Kong to reduce emissions. Emission caps were introduced, with allowances for the trading of emission credits. However, local power stations were using equipment built in the 1980s and 1990s, making it difficult for them to meet the new emissions requirements. The situation presented a new challenge, which involved a choice of either improving the existing equipment, or using emissions trading to meet the emission caps. This study reviews the background on emissions in Hong Kong and the surrounding regions, the “cap and trade” system, and the technologies used for power generation and emission reduction. A modeling approach is adopted to simulate the equipment, the electricity dispatching requirements, and the costs of either reducing emissions or trading emission credits. Data from a power station in Hong Kong was chosen for the simulation. Different options were simulated in the model to identify the optimal strategy. The results were then compared with the plan for emission reduction. This study demonstrates that a modeling approach using linear programming can analyze the complicated options involving emission reduction and investments to achieve an optimized business solution.     

不同碳源刺激对老化污染土壤中PAHs降解研究

采用室内模拟试验,研究追加葡萄糖、DL-苹果酸、柠檬酸三钠、脲和乙酸铵碳源刺激下对老化污染土壤中PAHs的降解规律.结果表明,培养第1周内,添加碳源处理土壤CO2的释放量显著大于对照,其中外加DL-苹果酸处理土壤所释放的CO2量最大.各处理CO2的平均释放量顺序为脲>葡萄糖≈柠檬酸三钠≈DL-苹果酸≈乙酸铵>对照.添加碳源处理土壤所挥发的PAHs要显著小于对照,且3种PAHs的挥发量大小顺序为菲>荧蒽>苯并(b)荧蒽.添加碳源处理土壤中菲、荧蒽及苯并(b)荧蒽的平均降解速度均大于对照,其中添加DL-苹果酸和脲处理土壤中菲、荧蒽及苯并(b)荧蒽的降解较快.3种PAHs化合物之间相比较,苯并(b)荧蒽的残留比例最大,在72%～81%之间;其次为荧蒽,在53%～70%之间;菲最少,在27%～44%之间.     

山东半岛南部近海表层沉积物中脂类生物标志物的组成及形态分析

分析了山东半岛南部近海表层沉积物中游离态和碱不稳定结合态脂类物质的组成,结果显示:脂肪酸呈现以16∶0为主峰的单峰形分布趋势,具明显偶碳优势,海源为其主要来源,脂肪酸主要以结合态形式存在,不同类别的脂肪酸形态分布略有差异,脂肪酸的结构和来源是影响脂肪酸形态分布的重要因素;同样以海源为主的甾醇则主要以游离态形式存在,但陆源甾醇的结合态比重相对较高;烷烃呈现以C29烷烃为主峰的单峰形分布趋势,陆源输入是其主要来源;烷烃主要以游离态形式存在,且UCM(不可分辨成分)峰仅出现在游离态烷烃的气相色谱图中。     

黔中喀斯特石漠化区不同小生境常见木本植物水分来源特征

选择黔中清镇市王家寨小流域内不同石漠化植物群落,通过分析测定喀斯特小生境内5种常见木本植物,鼠李、火棘、烟管荚蒾、圆果化香和云贵鹅耳枥与其潜在水源稳定性氢氧同位素组成,研究植物水分来源特征,并通过线性混合模型确定水源贡献比,探讨喀斯特小生境植物水分利用对石漠化过程的适应与响应。结果表明:多数情况下,研究区不同小生境内各植物种在雨季同时利用土壤水和表层岩溶带水,对土壤水的利用比例大于表层岩溶带水。各植物种对表层岩溶带水的利用比例随着石漠化的进行而减小。常绿灌木火棘、鼠李和烟管荚蒾在轻度、无石漠化样地同时利用土壤水和表层岩溶带水,但在中、强度石漠化则多利用土壤水,落叶小乔木圆果化香和云贵鹅耳枥在无石漠化同时利用土壤水和表层岩溶带水,而在轻度石漠化样地仅利用土壤水,这跟不同样地植被类型、干扰方式、土壤情况及裂隙发育等不同有关。     

非常规水源补给城市河流富营养化时空变化规律及风险研究

选择典型非常规水源补给城市河流(凉水河)为研究对象,阐述了凉水河典型河段水体中营养元素(氮、磷)的时空分布特征,并评价其富营养化状态.为期1年的监测结果表明:研究河段水体中TN、TP平均质量浓度分别为25.70 mg·L-1和1.78 mg·L-1,分别为地表水Ⅴ类标准的12.9倍和8.9倍.在时间尺度上,凉水河研究河段水体中TN、NH+4-N质量浓度冬季较高,夏季反而较低;水体中TP和SRP质量浓度全年基本一致.在空间尺度上,水体中TN和NH+4-N质量浓度变化趋势随土地利用类型变化趋于一致,均在城镇区域沿河流方向逐渐上升,至农村区域平缓波动;水体中TP和SRP质量浓度均沿河流方向呈逐渐上升趋势.通过计算对数型幂函数普适指数,发现凉水河研究河段无论是在时间尺度还是空间尺度均处于"极富"营养状态(EI=93.49),富营养化现象已十分严峻.     

Characteristics and anthropogenic sources of carbonyl sulfide in Beijing

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.     

广西某城市饮用水水源地重金属健康风险评价

为阐明城市饮用水水源地重金属污染物的健康风险水平,根据广西某市主要的3处饮用水水源地水质监测结果,采用美国环境保护署(US EPA)推荐的健康风险评价模型,对水源地原水中Cr、As、Cd、Pb、Cu、Hg、Fe和Zn等重金属通过饮用水途径引起的环境健康风险进行评价。结果表明:非致癌物质对成人和儿童引起的总非致癌风险在10-10~10-9a-1之间,远低于US EPA推荐的最大可接受风险水平(10-4a-1);致癌物质对成人和儿童引起的人均年致癌风险大小顺序均为CrAsCd;河流、湖库型水源地总致癌风险均超过US EPA推荐的最大可接受风险水平(10-4a-1),其中儿童人群总致癌风险在8.43×10-5~6.26×10-4a-1之间,明显高于成人6.05×10-5~4.52×10-4a-1的水平。Cr对儿童和成人总致癌风险贡献最高,是最主要的致癌物。     

东江干流水体氮的时空变化特征及来源分析

为了防治东江氮污染并进行针对性水体治理,于2013年7月(丰水期)和2014年1月(枯水期)全面调查了东江干流水体氮的时空变化特征,并利用附生藻的稳定性氮同位素示踪技术对东江水体氮进行了溯源研究.结果表明,TN、NO-3-N、NH+4-N在丰水期的平均浓度分别为2.70、1.63、0.21 mg·L-1,高于枯水期(TN,2.04 mg·L-1;NO-3-N,1.49 mg·L-1;NH+4-N,0.31 mg·L-1);东江水体氮含量较高,且主要以NO-3-N形态存在.各形态氮浓度自上游至下游的变化趋势表现为,TN和NO-3-N先递减再升高,NH+4-N则逐渐递增.稳定性氮同位素示踪表明,面源输入的人畜粪便、养殖废水及农业化肥等是上游区域氮的主要来源,贡献率约占91%;而在下游区域,城市污水的贡献率逐渐增大,并成为氮的主要来源,贡献率达到54%.     

Characteristics and anthropogenic sources of carbonyl sulfide in Beijing

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.     

人工湿地空气微生物群落碳源代谢特征

采用BIOLOG-GN微平板分析自由表面流人工湿地空气微生物群落碳源代谢特征,阐明空气微生物群落代谢功能与环境因子相关性.结果表明,不同季节人工湿地空气微生物AWCD值、优势群落及Mc Intosh指数均存在差异,春季和夏季空气微生物碳源代谢强度明显高于秋季和冬季(P0.01);4个季节人工湿地空气微生物优势群落依次为羧酸类代谢群落、糖类代谢群落、聚合物类代谢群落和羧酸类代谢群落,夏季空气微生物对6类化合物的利用水平高于其他季节(P0.05).主成分分析显示,秋季和冬季空气微生物碳源代谢特征相似,但与春季和夏季差别较大,胺类是区分人工湿地夏季与春季、秋季和冬季的主要碳源类型,羧酸类是区分春季与秋季和冬季空气微生物代谢差异的主要碳源类型.不同季节人工湿地空气微生物群落结构主导影响因子存在差异.