田间施用锌肥对小麦籽粒镉累积的影响及施用风险

锌（Zn）和镉（Cd）的交互作用是近年来小麦Cd污染防治的重要研究方向.以华北地区典型小麦田为研究对象,通过田间试验,探究Zn肥对土壤-小麦系统Cd污染的控制效果和施用风险.结果表明,低用量Zn处理下,济源和开封两地小麦籽粒Cd含量均呈下降趋势,与对照相比下降幅度分别为33.4%和25.3%.高用量Zn处理下,两地小麦籽粒Cd含量不降反升,与低用量Zn处理下小麦籽粒Cd含量相比增幅为22.4%和34.2%.施Zn后两地土壤Zn总量和有效态含量均有显著升高,且造成了土壤Cd的部分活化.典型相关分析（CCA）显示,当土壤ω（Zn）小于200 mg ·kg^-1时,土壤Zn是土壤-小麦系统Cd富集的主要影响因子,而当土壤ω（Zn）大于200 mg ·kg^-1时,土壤Cd的活化是影响小麦籽粒Cd富集的主要原因.回归分析显示土壤Cd/Zn降至0.0089时（低用量Zn）,Zn和Cd表现出拮抗效应,土壤Cd/Zn降至0.0078时（高用量Zn）,Zn和Cd表现出协同效应.针对区域Cd污染特征,调整Zn肥用量可以提高污染防治效率并避免加剧Cd污染危害.     

青南地区城镇污水处理厂综合效率评估分析

青南地区地处青藏高原腹地,是我国多条大江大河发源地,该地区污水处理对下游江河水环境质量改善具有重要意义.对青南地区(玉树、果洛和黄南)污水处理厂的综合效率进行定量评估分析并指出制约其效率提升的因素,对推动该地区污水处理产业的后续发展具有重要意义.因此,本文以青南地区11座城镇污水处理厂为研究对象,利用层次分析法和模糊综合分析法构建的模糊层次分析模型,从技术性能、经济性能、运行管理三个层面选取指标对模型进行量化,评估青南地区各污水处理厂的综合效率.结果表明:污水处理厂的综合得分在80分以上的只有1座,50—80分的有4座,50分以下的有6座,平均得分只有50.88分,表明该区域污水处理厂综合运行效率并不理想.通过实地调研,结合分析各污水处理厂表现较差的指标,发现该地区雨水收集率较低、低温冻裂管网等问题是导致污水处理效率偏低的主要原因.同时,未进行完备的污水处理设施建设与未完成提标改造是导致污水处理厂整体运行效果差等问题的重要原因.因此各污水处理厂应进一步加强设施建设,采取改进措施提高污水处理效率,防止管网等设备破裂导致污水污染环境,节约药费、电耗、人工费等运行费用,进一步提高青南地区污水处理厂的技术性能、运行管理和经济效益.     

黔西南汞铊矿废弃物中污染物释放的联合调控研究

为评价植生改良与先锋植物联合调控作用对矿产采冶废弃物中污染物迁移的控制情况,以黔西南兴仁市滥木厂大量露天堆存的汞铊矿废弃物（采冶废渣、尾矿、废石等混合物）为研究对象,选择当地广泛存在的碳酸盐岩、腐熟牛粪作为植生改良剂,并种植三叶草和黑麦草作为先锋植物进行联合调控,通过淋滤实验评价其对废弃物中高毒性污染物Hg、Tl、As和Sb释放的抑制效果。结果表明：对照组废弃物淋滤3次所得淋滤液中Hg、Tl含量平均为14.8 μg/L和170.6 μg/L,As和Sb平均为22.1 μg/L和4.9 μg/L,在雨水淋溶下具有持续释放进入环境的风险;联合调控可对废弃物中Tl和Hg的释放有明显的抑制效果,其中淋滤液Tl含量降为对照的12.2%～54.1%,10%碳酸盐岩梯度的混种组淋滤液Tl含量为19.6 μg/L,效果最好;5%、10%碳酸盐岩梯度的三叶组和混种组淋滤液中Hg含量显著低于对照水平（p<0.05）,较对照降低34.5%～47.9%;而联合调控则致使废弃物中As、Sb释放,相关性分析表明,植生改良剂添加引起的废弃物基质中溶解性有机质含量增加与植物诱导下游离氧化铁的溶解可能是导致As、Sb释放的关键因素。形态分析结果表明,联合调控促使汞铊矿废弃物中Hg、Tl向残渣态转变,而促使残渣态As、Sb占比下降导致其活化。综上,对汞铊矿废弃物采用植生改良剂-先锋植物联合调控可显著抑制Hg、Tl的释放,但需考虑所加植生改良剂中溶解性有机质增加及废弃物基质中游离氧化铁溶解引起的As、Sb活化与释放带来的环境风险。     

低碳氮比进水AAO污水处理厂低碳运行

为探明低碳氮比进水条件下AAO污水处理厂的碳排放特征,提出可行的低碳运行策略,基于排放因子法对7座低碳氮比进水AAO污水处理厂(分为AAO组和AAO-MBR组)运行1a产生的碳排放进行核算与评价,对具有显著低碳表现的污水处理厂开展全流程分析剖析其碳减排途径。结果表明,电耗和N₂O排放是主要碳排放来源,分别贡献49.43%和25.75%的碳排放。AAO-MBR组以间接碳排放为主,电耗碳排放占至约60%,而AAO组生物作用导致的直接碳排放占主导。AAO组平均吨水比碳排放显著低于AAO-MBR组(0.47和0.79kgCO_2eq/m³),更具低碳运行潜力。7座污水处理厂中,WWTP7各项比碳排放评价指标均为最低,意味着其最具低碳运行能力。充分利用进水碳源,多路径协同脱氮除磷同时精准控制溶解氧浓度避免过曝气是其大幅削减能耗和物耗,实现碳减排的关键路径。     

污水处理厂生物气溶胶抗生素抗性污染特征

为探究污水处理厂生物气溶胶抗生素抗性基因（ARGs）污染特征,在济南市某污水处理厂采用宏基因组测序技术对厂界内及周边生物气溶胶样本及污水或污泥样本进行分析.结果表明,相比于上风向,厂界内和下风向生物气溶胶具有更多的ARGs亚型种类数和更高的总相对丰度.厂界内与上风向生物气溶胶ARGs组成存在显著的差异性,差异度为47.57%;而厂界内与下风向生物气溶胶ARGs组成的差异性不显著,且差异度下降至33.98%.上风向背景空气和污水或污泥均是厂界内生物气溶胶ARGs的重要来源,两者总的源的贡献大于63.92%.共检测到43种ARGs亚型（8种ARGs主型）在至少一处污水处理单元极易负载于生物气溶胶颗粒逸出.本研究可为污水处理厂生物气溶胶抗生素抗性污染的风险评估和控制提供理论依据.     

Drivers of microbial beta-diversity in wastewater treatment plants in China

As one of the most well-documented biogeographic patterns, the distance-decay relationship provides insights into the underlying mechanisms driving biodiversity distribution. Although wastewater treatment plants (WWTPs) are well-controlled engineered ecosystems, this pattern has been seen among microbial communities in activated sludge (AS). However, little is known about the relative importance of environmental heterogeneity and dispersal limitation in shaping AS microbial community across China; especially they are related to spatial scale and organism types. Here, we assessed the distance-decay relationship based on different spatial scales and microbial phylogenetic groups by analyzing 132 activated sludge (AS) samples across China comprising 3,379,200 16S rRNA sequences. Our results indicated that the drivers of distance-decay pattern in China were scale-dependent. Microbial biogeographic patterns in WWTPs were mainly driven by dispersal limitation at both local and national scales. In contrast, conductivity, SRT, and pH played dominant roles in shaping AS microbial community compositions at the regional scale. Turnover rates and the drivers of beta-diversity also varied with microorganism populations. Moreover, a quantitative relationship between dispersal limitation ratio and AS microbial turnover rate was generated. Collectively, these results highlighted the importance of considering multiple spatial scales and micro-organism types for understanding microbial biogeography in WWTPs and provided new insights into predicting variations in AS community structure in response to environmental disturbance.     

加油站三次油气回收技术现状分析与性能提升技术研究

针对近年来加油站三次油气回收设备排放频繁超标的问题,对加油站已投用的三次油气回收设备进行调研分析,找出导致三次油气回收设备排放超标的原因,通过数据模拟对相关结论进行验证,提出解决三次油气回收设备超标排放问题的技术提升措施。     

低温环境下人工湿地植物组配对养殖废水的处理效果研究

强化低温环境下人工湿地的污水处理能力,对于促进人工湿地的应用推广具有重要的意义。本研究利用绿狐尾藻(Myriophyllum aquaticum)和菖蒲(Acorus calamus L.)两种湿地植物,在室外低温环境下(＜15℃),研究人工湿地植物组配对不同负荷养殖废水的处理效应及关键影响因素。结果表明,在不种、单种和不同顺序混种绿狐尾藻(M.aquaticum)和菖蒲(A.calamus L.)处理下,菖蒲+绿狐尾藻组合湿地(AM)对TN、TP和COD去除率均为最高,在低负荷和高负荷环境下平均去除率分别为74.2%、71.3%、83.0%和67.3%、81.9%、75.3%。相较于空白对照和植物单种的湿地系统,植物混种系统的DO较高,且AM处理在低负荷和高负荷环境下均能保持较高的C∶N。根据Pearson相关性以及PCA分析,DO与TN、NH⁺₄-N去除率显著相关(P<0.05),C∶N与COD去除关联性最好。可见,菖蒲+绿狐尾藻植物组合可能通过改善DO和C∶N等湿地微环境条件来增强湿地对污染物的去除,能够作为低温环境下强化湿地对污染物去除的一种有效措施。     

Assessing the “design paradox” with life cycle assessment: A case study of a municipal solid waste incineration plant

One of the most important processes in an integrated waste management system is incineration, which, among the different waste management disposal options still remains a critical waste treatment system. New dynamics and approaches have to be developed to embrace such a wide and complex topic, and better knowledge and assessment of incineration are strategically significant to define future environmental scenarios.Life cycle assessment (LCA), as a tool to optimise process-operating conditions and to support decision-making process, is often applied to investigate processes under design in various sectors, since choices made in the development phases can affect the future environmental profile. However, even if the greatest opportunity to improve a process from an environmental perspective is during the design phase, at the same time the knowledge is limited, in accordance with the so-called “design paradox”.Thus, in this context, this study used LCA methodology to quantitatively assess the extent to which the environmental impact of an incineration line reflects the environmental burdens perceived during the design phase. A comparative LCA was conducted at the design phase and under operating conditions at an Italian municipal solid waste incineration plant.The outcomes of the study indicated that for almost all of the categories analysed, the impacts associated with the process under design overestimated the impacts associated with the operating process, with the exception of climate change and water depletion. The results suggested that after the conduction of an LCA at the design phase of a process, an LCA of the operative conditions should be carried out to verify how much the over- or under-estimations affected the results.     

银纳米颗粒对黄菖蒲早期生长和生理特征的影响

N-AgNPs（银纳米颗粒）暴露对湿地植物的生长发育有重要影响,而N-AgNPs对大型湿地植物黄菖蒲（Iris pseudacorus）的影响尚不清楚.选取湿地植物黄菖蒲为受试物种,采用室内土培法分析柠檬酸钠包覆的N-AgNPs对黄菖蒲早期生长和生理特征的影响.结果表明:①不同ρ（N-AgNPs）〔分别为0、5、10、15、20 mg/L,依次记为N0（对照）、N5、N10、N15、N20〕处理和作用时间均会影响黄菖蒲生长和生物量积累.培养初期（0~14 d）,N5、N10处理会抑制黄菖蒲生长,而N15、N20处理会促进黄菖蒲生长;培养后期（14~35 d）,不同ρ（N-AgNPs）处理均抑制黄菖蒲生长.整个培养期内（0~35 d）,N5、N10处理均抑制黄菖蒲地上、地下生物量积累,而N20处理会促进黄菖蒲地上、地下生物量积累.②不同ρ（N-AgNPs）处理均降低了黄菖蒲叶绿素含量,提高了PSⅡ（光系统Ⅱ）反应中心的光能转换效率,降低了光氧化损伤的发生率;N5、N10、N15处理下黄菖蒲叶片PSⅡ功能反应中心的开放度降低、光合电子传递速率（ETR）变慢;N5和N20处理下黄菖蒲叶片光合电子传递活性（qP）增大,而N10和N15处理下光合电子传递活性降低.③各ρ（N-AgNPs）处理均显著降低了黄菖蒲叶片中的丙二醛含量,膜脂过氧化作用减弱;同时,增加了黄菖蒲叶片中w（脯氨酸）,对黄菖蒲产生较强的胁迫.研究显示,随着培养浓度的增加,ρ（N-AgNPs）对黄菖蒲生物量累积的影响由抑制作用变为促进作用;各ρ（N-AgNPs）处理均会降低黄菖蒲的叶绿素含量、增加w（脯氨酸）,对黄菖蒲的生长产生胁迫.