青岛近海生物气溶胶中可培养微生物浓度及群落多样性的季节变化

为了研究近海生物气溶胶中可培养微生物浓度和群落多样性,于2009年7月~2010年6月在青岛两个采样点连续采集生物气溶胶样品,分析了其中陆源细菌、海源细菌、陆源真菌和海源真菌的浓度,并计算了Shannon-Weiner指数、Simpson’s指数和Pielou指数.结果表明,陆源细菌和海源细菌月均浓度分别为12~436 CFU·m-3和25~561 CFU·m-3,陆源真菌和海源真菌月均浓度分别为0~817 CFU·m-3和11~1 346 CFU·m-3之间.陆源细菌、海源细菌、陆源真菌和海源真菌浓度在冬季月份较低,2月达到最低值,在春夏月份较高.海源微生物对总可培养类微生物的贡献高于陆源,平均占63%.可培养微生物物种数在17~102之间,与微生物浓度具有一定的相关性,但并未呈现出明显的季节变化.3种指数表明,生物气溶胶中陆源细菌、海源细菌、陆源真菌和海源真菌的群落结构在2月最简单,1月、11月和5月群落多样性较高,群落多样性与浓度的季节变化特征并不一致,而且不同类别的微生物群落存在季节和空间差异.     

Growth responses of Picea mongolica seedlings to defoliation rate

Picea mongolica W. D. Xu. is an endemic species in China. The spruce forest is only found in semi-arid habitat in Inner Mongolia Autonomous Region of China. Based on the simulative defoliation experiment, it was proved that Picea mongolica seedlings had the compensatory and overcompensatory effects under the certain defoliation rate. The results of variance analysis on growth indexes showed that in PM I (natural regeneration seedlings under Picea mongolica forest), the differences of H1 (height in June 23 ) and H2 (height in September 3) were extremely significant, and the difference of D(diameter at the breast height) were not significant. In PM Ⅱ (artificial regeneration seedlings under Betula platyphylla Suk. forest), the difference of H1 was significant, the difference of H2 was not significant, and the difference of D was extremely significant. The regression equations were established and the compensatory and overcompensatory points were obtained. In PM I, the compensatory points of H1, H2, and D were 0.7628, 0.7436, 0.5725, and the overcompensatory points were 0.6056, 0.5802 and 0.2909 respectively. In PM Ⅱ, the compensatory points of H1, H2, and D are 0.5012, 0.3421, 0.2488, and the overcompensatory points are 0.4137, 0.2633 and 0.0747 respectively. These results suggested that the induction of compensatory growth mechanisms in spruce seedlings required a threshold level of defoliation, and the insects in Picea mongolica forest could be controlled in a certain de clree.     

某典型石油化工园区冬季大气中VOCs污染特征

利用TH-300B挥发性有机物(volatile organic compounds,VOCs)在线监测系统于2014年12月~2015年2月对我国某石油化工园区的VOCs进行连续在线监测.分析了其组成特征、时间变化特征、来源以及光化学活性特征.结果表明,研究区冬季大气中VOCs的混合体积分数较高,烷烃占据主导地位,占TVOCs的86.73%;TVOCs、烷烃、烯烃、芳香烃的昼夜变化特征均表现为夜间高而白天低,且烷烃、烯烃的变化与TVOCs较为一致.利用主成分分析-多元线性回归(PCA-MLR)模型解析得到5个因子,分别表征燃料挥发源、工业排放源、汽油车尾气和植物排放混合源、柴油车尾气排放源和燃料燃烧源,其贡献率分别为60.02%、8.50%、2.07%、12.21%、17.20%.利用Propy-equiv法和MIR法计算得出该研究区冬季大气中各类VOCs对臭氧生成的相对贡献率的大小均表现为烷烃烯烃芳香烃,其中环戊烷、正丁烷和1-戊烯的贡献率较高,气团光化学年龄较长.     

秸秆发酵产氢的影响因素研究

以加热预处理的厌氧活性污泥为接种物,以秸秆（稻草、麦杆）为发酵底物进行微生物产氢实验,研究了不同秸秆粒径、纤维素酶用量、预处理方法、发酵液pH值对秸秆发酵产氢速率以及产氢气量的影响.其中颗粒粒径为170 μm的稻草经过NaOH预处理,按照底物与纤维素酶用量1∶1的比例酶解,进而发酵产氢的单位总产氢量为90.5 mL/g,最大单位产氢速率为0.58 mL/(h·g).     

成都经济区土壤中HCH和DDT含量及其分布特点

通过对成都经济区土壤中HCH各异构体、DDT及其衍生物的含量及分布特点研究,得出成都经济区土壤中HCH和DDT都有较高的检出率,含量变化幅度也很大,含量较高点主要分布在化工厂附近。对比其他地区研究结果,成都经济区HCH含量较低,DDT含量较高。以西藏地区作为背景值,HCH有一定的污染,DDT污染较为严重。     

排水管道沉积物控制的研究进展

排水管道沉积物雨天受冲刷而造成的河湖水体污染,已成为当前我国水环境质量持续改善面临的困境之一。深入了解管道沉积物及其沉积机制对水体污染治理至关重要。综述了管道沉积物的形成与特性,微生物或沉积物中胞外聚合物(extracellular polymeric substance,EPS)的主要组分和相关性质对沉积物抗冲刷特性的影响。结果显示:排水管道沉积物主要是由污水携带的固体颗粒发生沉降而形成,主要包含底层粗颗粒沉积物、有机层和生物膜3类。由于沉积物中富含微生物并可分泌EPS,而EPS的黏性能显著增加管道沉积物的抗冲刷性。通过控制或降解沉积物EPS中的多糖组分,可降低沉积物的抗冲刷性能,有望为控制管道沉积物淤积提供新思路。目前国内外控制管道沉积物淤积的方法主要包括离线和在线水力冲刷或机械清淤。今后的研究方向应着力在真实的排水管网中系统地研究沉积物耐冲刷特性及其影响因素,进而提出更为有效的控制技术。     

低碳约束下黑瞎子岛开放开发战略产业选择与资源环境适应性政策调整研究

低碳经济条件下,如何选择和发展战略产业,是应对全球气候变化,推动经济可持续发展的战略议题。本研究针对黑瞎子岛开放开发的战略产业选择进行系统分析基础上,探讨提出其资源环境适应性政策调整的建议。具体建议如下:第一,综合运用多种手段和形式,加强生态旅游管理;第二,逐步完善碳交易市场体系,为制造业减排提供激励机制;第三,制定规范的产业发展政策,支持企业发展绿色物流。     

Assessing field vulnerability to phosphorus loss in Beijing agricultural area using Revised Field Phosphorus Ranking Scheme

Guanting Reservoir,one of the drinking water supply sources of Beijing,suffers from water eutrophication.It is mainly supplied by Guishui River.Thus,to investigate the reasons of phosphorus(P)loss and improve the P management strategies in Guishui River watershed are important for the safety of drinking water in this region.In this study,a Revised Field P Ranking Scheme(PRS)was developed to reflect the field vulnerability of P loss at the field scale based on the Field PRS.In this new scheme,six factors are included, and each one was assigned a relative weight and a determination method.The affecting factors were classified into transport factors and source factors,and,the standards of environmental quality on surface water and soil erosion classification and degradation of the China were used in this scheme.By the new scheme,thirty-four fields in the Guishui River were categorized as"low","medium"or"high"potential for P loss into the runoff.The results showed that the P loss risks of orchard and vegetable fields were higher than that of corn and soybean fields.The source factors were the main factors to affect P loss from the study area.In the study area,controlling P input and improving P usage efficiency are critical to decrease P loss.Based on the results,it was suggested that more attention should be paid on the fields of vegetable and orchard since they have extremely high usage rate of P and high soil test of E Compared with P surplus by field measurements,the Revised Field PRS was more suitable for reflecting the characteristics of fields,and had higher potential capacity to identify critical source areas of P loss than PRS.     

降解纤维素产甲烷的四菌复合系

自然环境中通常是微生物群落协同完成纤维素的降解,构建可降解纤维素的混菌体系是认识微生物相互作用的关键.利用富集培养法,结合变性梯度凝胶电泳(DGGE)指纹检测技术以及厌氧滚管技术,建立了一种筛选简单降解纤维素产甲烷复合菌系的方法.利用此方法从青藏高原若尔盖高寒湿地分离到一个由4株菌构成的降解纤维素产甲烷的稳定菌系.结果表明,该复合菌系由纤维素水解菌Clostridium glycolicum、非纤维素水解菌Trichococcus flocculiformis和Parabacteroides merdae、产甲烷古菌Methanobacterium subterraneum等具有不同功能的4种菌株组成,且在这4株菌的共同作用下可将纤维素直接转化为CH4.该简单复合系的获得为今后纤维素转化甲烷复合菌系的代谢控制和遗传改造提供了一个平台.     

纳米银与石墨烯对土壤微生物及土壤酶的影响

采用室内暗培养试验分别探究了纳米银与石墨烯对土壤微生物及土壤酶的不同影响.将不同剂量的纳米银(0、10、100、150 mg·kg~(-1))与高纯石墨烯(0、10、100、1000 mg·kg~(-1))分别与等量棕壤充分混匀,然后进行暗培养.在第3、7、15、30和60 d时取样,测定土壤脲酶、土壤碱性磷酸酶、土壤脱氢酶和土壤过氧化氢酶的活性及土壤细菌、真菌和放线菌的数量,并在培养期间测定土壤呼吸速率及CO2累积量.结果表明,所有纳米银处理均抑制土壤的呼吸作用,并且剂量越高,抑制作用越明显;而石墨烯处理未对土壤呼吸产生显著影响.10 mg·kg~(-1)纳米银处理下,土壤真菌数量在整个培养期内均显著低于对照,土壤细菌在第60 d时也被显著抑制,但土壤放线菌数量无变化;与对照相比,100和150 mg·kg~(-1)的纳米银处理显著降低了土壤细菌、真菌、放线菌的数量.10和100 mg·kg~(-1)的石墨烯处理下,土壤细菌、真菌、放线菌数量则均无显著变化.1000 mg·kg~(-1)的石墨烯显著增加了土壤中细菌与真菌的数量,却对土壤放线菌数量无影响.纳米银处理显著抑制土壤脲酶、脱氢酶活性,却对土壤过氧化氢酶与磷酸酶活性基本无影响.10和100 mg·kg~(-1)石墨烯处理对土壤脲酶有一定的促进作用,1000 mg·kg~(-1)石墨烯处理对土壤过氧化氢酶和脱氢酶有一定的促进作用,而不同剂量的石墨烯在培养后期均对碱性磷酸酶产生抑制作用.总体来说,纳米银在一定程度上对土壤酶及土壤微生物结构产生了负面影响,而石墨烯对土壤酶及土壤微生物结构的影响不明显.