南京市饮用水源地抗生素污染特征及风险评估

采用固相萃取-液相色谱-串联质谱技术（SPE-HPLC-MS/MS）,对南京市饮用水源地抗生素含量及分布特征进行了分析.结果表明,17个采样点总浓度为0.56~1994.96 ng·L^-1,共检出5种大环内酯类、13种磺胺类、3种四环素类、8种喹诺酮类抗生素,平均浓度为0.30~37.07 ng·L^-1,其中检出浓度最高的抗生素为环丙沙星（CIP）,浓度为317.60 ng·L^-1,检出率最高的抗生素为克林霉素（CLI）,检出率为88.24%.与国内部分河流相比,南京市饮用水源地水体中大环内酯类、四环素类、喹诺酮类抗生素残留浓度处于较高水平.生态风险评估结果表明,点位S7具有最高的联合风险熵值（24.58）,氧氟沙星（OFX）的风险熵值最高,达到13.06;健康风险评估结果表明,9种抗生素对人体健康的风险熵Q_H为1.70×10^-3~9.47,强力霉素（DOX）、诺氟沙星（NOR）、恩诺沙星（ERX）、CIP和OFX对大部分年龄段的人体健康具有高水平风险.     

黑河流域底栖动物群落结构及水质评价

为了解黑河流域上中游底栖动物群落结构特征及其与环境因子之间的关系,于2018年8月对研究区域17个采样点的底栖动物和水体理化指标进行调查研究.共鉴定出底栖动物43种,其中节肢动物34种（79.1%）,软体动物7种（16.3%）,环节动物2种（4.6%）;就整个研究区域而言,优势种为大蚊（Tipulidae）、豆娘幼虫（Damselfly）、水蜘蛛（Argyroneta）、耳萝卜螺（Radix auricularia）、琥珀螺（Suecinea sp.）、白旋螺（Gyraulusalbus）,干、支流优势种分布趋势为干流（6种）优于支流（5种）;底栖动物平均密度和平均生物量分别为77ind/m²和3.7423g/m²现存量存在显著空间差异,整体上干流（1032ind/m²、60.0963g/m²）大于支流（276ind/m²、3.5233g/m²）,物种数干流（36种）大于支流（15种）;单因素方差分析显示,Shannon-Wiener多样性指数、Margalef丰富度指数及Pielou均匀度指数分布特征为干流大于支流.黑河流域上游支流和中游干流不同河段底栖动物物种组成呈空间异质性,而多样性指数对物种组成依赖性强,但因黑河流域底栖动物物种组成受自然因素和人类活动双重影响程度差异较大,使得Shannon-Wiener多样性指数、Margalef丰富度指数及Pielou均匀度指数不适合黑河水质评价.依据BI指数和综合污染指数评价表明,黑河上游支流水质优于中游干流.根据底栖动物与环境因子之间的相关矩阵分析并结合RDA分析表明：BOD₅、水温（WT）、电导率（EC）、DO、溶解性总固体（TDS）、COD_Mn及盐度是影响底栖动物群落结构的主要环境因子.     

船舶排放及不确定性对中国空气质量的影响

船舶排放是我国沿海地区重要的人为排放源,但现有的船舶排放评估研究大多只关注区域尺度的影响分析,而且忽视了排放清单的不确定性,这在一定程度上削弱了评估结果的可靠性.为此,本文利用WRF-SMOKE-CAMQ空气质量模型,定量评估了船舶排放及其不确定性对我国七大沿海港口城市夏季空气质量的影响,结果表明：船舶排放对我国主要沿海港口城市的SO₂、NO_x和PM_2.5浓度贡献范围分别为16.5%~62.5%、21.9%~72.9%和5.9%~26.0%,尤其对宁波、青岛和深圳等港口城市空气质量的影响显著,主要是由于港口较高的船舶排放以及气象传输两方面原因造成的;如果考虑船舶排放清单的总量不确定性,船舶排放对沿海港口城市夏季SO₂、NO_x和PM_2.5的影响分别呈现1.0~3.1,2.1~5.5,0.3~0.9μg/m³的波动;考虑船舶排放清单的时空分配不确定性,船舶排放对沿海港口城市夏季SO₂、NO_x和PM_2.5的影响分别呈现1.9~15.7,5.1~29.3,0.6~2.5μg/m³的波动.可见,船舶排放清单的不确定性对沿海城市船舶排放贡献影响量化有明显的影响.所以在评估船舶排放对港口城市空气质量的影响时,要考虑船舶排放清单的不确定性,尤其是时空分配的不确定性.而合理的时空分配能够提高船舶排放清单的质量和对沿海空气质量模拟的准确性.     

Aerosol optical properties under different pollution levels in the Pearl River Delta (PRD) region of China

To clarify the aerosol hygroscopic growth and optical properties of the Pearl River Delta(PRD)region,integrated observations were conducted in Heshan City of Guangdong Province from October 19 to November 17,2014.The concentrations and chemical compositions of PM_(2.5),aerosol optical properties and meteorological parameters were measured.The mean value of PM_(2.5) increased from less than 35(excellent) to 35-75 μg/m~3(good) and then to greater than 75 μg/m~3(pollution),corresponding to mean PM_(2.5) values of 24.9,51.2,and 93.3 μg/m~3,respectively.The aerosol scattering hygroscopic growth factor(f(RH = 80%)) values were 2.0,2.12,and 2.18 for the excellent,good,and pollution levels,respectively.The atmospheric extinction coefficient(σext)and the absorption coefficient of aerosols(σ_(ap)) increased,and the single scattering albedo(SSA)decreased from the excellent to the pollution levels.For different air mass sources,under excellent and good levels,the land air mass from northern Heshan had lower f(RH) and σ_(sp) values.In addition,the mixed aerosol from the sea and coastal cities had lower f(RH) and showed that the local sources of coastal cities have higher scattering characteristics in pollution periods.     

2018年春节期间京津冀地区污染过程分析

为了解2018年春节期间京津冀地区空气污染情况,利用近地面污染物浓度数据、激光雷达组网观测数据,结合WRF气象要素、颗粒物输送通量和HYSPLIT气团轨迹综合分析污染过程.结果表明,春节期间出现3次污染过程.春节前一次污染过程,各站点PM_2.5浓度均未超过200μg/m³;除夕夜,廊坊站点PM_2.5峰值浓度达到504μg/m³,是清洁天气的26倍;年初二~初五,各站点PM_2.5始终高于120μg/m³,且污染主要聚集在500m高度以下,北京地区存在高空传输,800m处最大输送通量达939μg/（m³·s）,此次重污染过程为一次典型的区域累积和传输过程.京津冀地区处于严格管控状态时,燃放烟花爆竹期间PM_2.5峰值浓度可达无燃放时PM_2.5峰值的3.2倍.为防止春节期间重污染现象的发生,需对静稳天气下燃放烟花炮竹采取预防对策.     

二乙烯三胺五甲叉膦酸酸解磷尾矿的实验探究

为减少磷尾矿堆积带来的环境污染问题,实现磷尾矿的钙、镁、磷元素的分离,以高镁磷尾矿为原料,采用二乙烯三胺五甲叉膦酸(DTPMP)进行酸解,探究磷尾矿中主要物相在DTPMP中的分解机制,并通过单因素实验探究pH、反应时间、反应温度及投料比对磷尾矿中MgO、CaO和P_2O_5分解率的影响。实验结果表明:pH对P_2O_5的分解率影响较大,高温更有利于尾矿中镁的溶出,在pH为2. 5,反应时间为60 min,反应温度为80℃,投料比为1. 56时,MgO、CaO和P_2O_5的分解率分别达到61. 05%、38. 23%和9. 67%。     

排水管道沉积物微生物群落及环境因子分析

选取北京市某区的排水管道沉积物进行取样,采用高通量测序手段分析,结果表明变形菌门、广古菌门、拟杆菌门、厚壁菌门是排水管道沉积物微生物中的优势门类;在纲水平上,δ-变形菌纲、甲烷微菌纲、梭菌纲、拟杆菌纲占相对优势;在属水平上,功能性微生物硫酸盐还原菌（SRB）和产甲烷古菌（MA）普遍存在于各处管道.在所选的6段管段中,管段S3、S4处MA的相对丰度分别为20.6%、40.8%,高于其他管段,厌氧产甲烷的潜能较大,有发生可燃气积累的风险;管段S5、S6处的SRB相对丰度分别为9.14%、8.19%,高于其他管段,硫酸盐还原为硫化物的潜能较大,存在管道腐蚀的风险.RDA分析表明污水的DO、水温、硫酸根、TN与管道沉积物中微生物群落存在相关性.     

Influence of environmental factors on arsenic accumulation and biotransformation using the aquatic plant species Hydrilla verticillata

Hydrilla verticillata(waterthyme) has been successfully used for phytoremediation in arsenic(As) contaminated water.To evaluate the effects of environmental factors on phytoremediation,this study conducted a series of orthogonal design experiments to determine optimal conditions,including phosphorus(P),nitrogen(N),and arsenate(As(Ⅴ))concentrations and initial pH levels,for As accumulation and biotransformation using this aquatic plant species,while also analyzing As species transformation in culture media after 96-hr exposure.Analysis of variance and the signal-to-noise ratio were used to identify both the effects of these environmental factors and their optimal conditions for this purpose.Results indicated that both N and P significantly impacted accumulation,and N was essential in As species transformation.High N and intermediate P levels were critical to As accumulation and biotransformation by H.verticillata,while high N and low P levels were beneficial to As species transformation in culture media.The highest total arsenic accumulation was(197.2±17.4) μg/g dry weight when As(V) was at level 3(375μg/L),N at level 2(4 mg/L),P at level 1(0.02 mg/L),and pH at level 2(7).Although H.verticillata is highly efficient in removing As(Ⅴ) from aquatic environments,its use could be potentially harmful to both humans and the natural environment due to its release of highly toxic arsenite.For cost-effective and ecofriendly phytoremediation of As-contaminated water,both N and P are helpful in regulating As accumulation and transformation in plants.     

Performance of different macrophytes in the decontamination of and electricity generation from swine wastewater via an integrated constructed wetland-microbial fuel cell process

Plants constitute a major element of constructed wetlands(CWs).In this study,a coupled system comprising an integrated vertical flow CW(IVCW) and a microbial fuel cell(MFC) for swine wastewater tre atment was developed to research the effects of macrophytes commonly employed in CWs,Canna indica,Acorus calamus,and Ipomoea aquatica,on decontamination and electricity production in the system.Because of the different root types and amounts of oxygen released by the roots,the rates of chemical oxygen demand(COD) and ammonium nitrogen(NH_4~+-N) removal from the swine wastewater differed as well.In the unplanted,Canna indica,Acorus calamus,and Ipomoea aquatica systems,the COD removal rates were 80.20%,88.07%,84.70%,and 82.20%,respectively,and the NH_4~+-N removal rates were 49.96%,75.02%,70.25%,and 68.47%,respectively.The decontamination capability of the Canna indica system was better than those of the other systems.The average output voltages were 520±42,715±20,660±27,and 752±26 mV for the unplanted,Canna indica,Acorus calamus,and Ipomoea aquatica systems,respectively,and the maximum power densities were 0.2230,0.4136,0.3614,and0.4964 W/m~3,respectively.Ipomoea aquatica had the largest effect on bioelectricity generation promotion.In addition,electrochemically active bacteria,Geobacter and Desulfuromonas,were detected in the anodic biofilm by high-throughput sequencing analysis,and Comamonas(Proteobacteria),which is widely found in MFCs,was also detected in the anodic biofilm.These results confirmed the important role of plants in IVCW-MFCs.     

Development of a static test apparatus for evaluating the performance of three PM2.5 separators commonly used in China

PM_(2.5) separator directly affects the accuracy of PM_(2.5) sampling.The specification testing and evaluation for PM_(2.5) separator is particularly important,especially under China's wide variation of terrain and climate.In this study,first a static test apparatus based on polydisperse aerosol was established and calibrated to evaluate the performance of the PM_(2.5) separators.A uniform mixing chamber was developed to make particles mix completely.The aerosol concentration relative standard deviations of three test points at the same horizontal chamber position were less than 0.57%,and the particle size distribution obeyed logarithmic normal distribution with an R~2 of 0.996.The flow rate deviation between the measurement and the set point flow rate agreed to within ± 1.0% in the range of -40 to 50℃.Secondly,the separation,flow and loading characteristics of three cyclone separators(VSCC-A,SCC-A and SCC112) were evaluated using this system.The results showed that the 50% cutoff sizes(D_(50)) of the three cyclones were 2.48,2.47 and 2.44 μm when worked at the manufacturer's recommended flow rates,respectively.The geometric standard deviation(GSD) of the capture efficiency of VSCCA was 1.23,showed a slightly sharper than SCC-A(GSD = 1.27),while the SCC112 did not meet the relevant indicator(GSD = 1.2 ± 0.1) with a GSD = 1.44.The flow rate and loading test had a great effect on D_(50),while the GSD remained almost the same as before.In addition,the maintenance frequency under different air pollution conditions of the cyclones was summarized according to the loading test.