低浓度Cd暴露对金鱼藻营养元素吸收与植物络合素(PCs)合成的影响

采用溶液培养方式,研究了水环境低浓度Cd(0.01～0.64 μmol/L)不同暴露时间段下,金鱼藻(Ceratophyllum demersum)体内营养元素的吸收状况和植物络合素(PCs)的响应规律.结果表明,Cd促进了微量营养元素Cu、Zn的吸收,抑制了Mn的吸收,对Fe的吸收无明显影响.金鱼藻对Cd表现出明显的吸收和积累效应,0.08　μmol/L Cd胁迫对金鱼藻生长产生了抑制作用.Cd暴露期间各处理组PCs诱导量与Cd处理浓度存在显著的响应关系,处理前期(7　d)当Cd浓度≥0.02　μmol/L时,表现为显著的诱导效应(p<0.05).随着暴露时间的延长,PCs诱导量有下降趋势,但仍明显高于对照.各不同处理时间段下PCs诱导量与Cd处理浓度存在良好的剂量效应关系.胁迫7 d时呈线性关系,胁迫14 d和21 d均表现为抛物线型.回归分析显示金鱼藻体内PCs的合成水平与Cd的生物毒性存在极显著的正相关关系.表明PCs可作为Cd胁迫的一项敏感的生化指标(biochemical indicator)用来评价和预测实际水环境中Cd的污染.     

苏州市空气质量的时间序列变化过程研究

城市空气质量水平是以空气质量指数(API)来表征的,API的时空变化可以反映城市空气质量的变化过程。文章以苏州市2002～2007年各月API值为研究对象,将其构成一组时间序列,采用时间序列理论中的小波分析原理和差分自回归滑动平均模型(ARIMA)原理对这组API序列进行趋势的辨识和数值预测,结果表明(1)苏州市近年来的空气质量水平不断提高,并将稳定保持在一个良好的水平上;(2)差分自回归滑动平均模型ARIMA(2,2,2)在拟合该地区API值时间尺度上的变化趋势效果较好,能够较好的预测苏州市月空气质量水平。     

异波折板厌氧废水处理技术研究

设计异波折板复合厌氧反应器,进行为期12个月的生活污水处理试验研究。试验结果表明,在温度处于(25±2)℃条件下,反应器的最佳水力停留时间(HRT)为6h。此时所对应的COD、TN、TP去除率分别为76.95%、36.56%、39.28%;最适厌氧污泥区容积百分比为45%～65%;最适进水COD浓度为150～800mg/L。控制HRT为6h,查明温度降至(7±1)℃时所对应的COD、TN、TP分别为63.53%、20.28%、22.35%;最大比甲烷生产率降至1.95mL(/gVSS·h)。此研究结果表明在北方地区低温度条件下应用该技术处理低浓度生活污水可行。基于试验结果,阐明了此厌氧生物处理技术处理低浓度生活污水的高效机理在于异波折板复合厌氧反应器具有高效传质和双层分阶段多生物相的特点。     

石化废水深度处理及脱盐的中试研究

针对石化行业污水回用处理设施很快失效的现状,开发了“集成式悬浮载体生物氧化－砂滤－臭氧活性炭处理－超滤反渗透”的组合工艺对炼油厂外排水进行深度处理.连续7个月的中试结果表明,处理后外排水中COD、NH3-N、BOD5、油和浊度等均优于回用水标准,可作为工业循环冷却水、绿化用水和办公等用水;常规深度处理的出水经过超滤反渗透处理后,电导率稳定在35~40μS/cm,可作为动力车间的新鲜水,不会发生膜污染和堵塞问题.尽管外排水的水质波动很大,但是组合工艺运行稳定、可靠,具有突出的抗冲击性能.     

稻鸭复合系统的温室气体排放及其温室效应

利用密闭箱技术和碱液吸收法.通过田间试验研究了稻鸭复合系统土壤CH4、N2O和CO2的排放规律及其温室效应.结果表明:①在水稻生长期间,CH4分别在分蘖期和抽穗期出现2个排放高峰.平均排放通量养鸭处理为(7.68±0.74)mg·m-2·h-1.常规淹水稻田(对照)为(9.53±0.40)mg·m-2·h-1;N2O排放通量呈现出在稻田淹水期间保持较低值,在稻田落干后迅速升高的趋势,平均排放通量养鸭处理为(0.092±0.073)mg·m-2·h-1,对照为(0.082±0.074)mg·m-2·h-1;而CO2的排放则在分蘖期和成熟期田面水逐渐落干后呈现2个排放峰,养鸭处理和对照的平均排放通量分别为(121.20±4.21)mg·m-2·h-1和(107.53±3.92)mg·m-2·h-1.②稻田养鸭显著地降低了CH4的排放.水稻整个生育期间排放量为18.41 g.m-2,比对照减少19.3%;而显著地提高了N2O的排放,整个生育期间排放量为0.2 g·m-2,比对照增加了10%;养鸭稻田土壤CO2的总排放量为273.66 g·m-2,对照为245.73 g·m-2,两者之间没有显著性的差异.③CH4是引起稻田温室气体综合温室效应的主体,其贡献率在60%左右,相对于常规稻作,稻田养鸭能有效降低甲烷的温室效应,使其温室气体的综合温室效应显著降低.说明在中国南部稻鸭共作是一个减缓全球温室效应的可行措施.     

西部管道工程HSE一体化组织管理应用研究

分析了我国管道工程项目HSE组织管理存在的问题,运用组织管理理论,提出了以业主为核心、EPC为主体、PMC为业主的延伸和细化的西部管道工程HSE一体化总体组织结构。     

Assessment of oxidative stress indices in a marine macro brown alga Padina tetrastromatica (Hauck) from comparable polluted coastal regions of the Arabian Sea, west coast of India

Oxidative stress and antioxidant defence systems were assessed in a marine brown alga Padina tetrastromatica, commonly occurring from the tropics. Lipid peroxidation (LPX) and H2O2 were measured as oxidative stress markers, and antioxidant defences were measured as catalase (CAT), glutathione S-transferase (GST) and ascorbic acid (AsA), in order to understand their dissimilarity with respect to pollution levels from selective locations along the central west coast of India. A significant increased levels of LPX, H2O2, CAT and GST were observed in samples from relatively polluted localities (Colaba and Karwar) when compared to less polluted locality (Anjuna), while AsA concentration was higher in algal samples from worst polluted region of Colaba. Heavy metals such as Cd and Pb were also higher in the vicinity of polluted areas compared to reference area. Variation of oxidative stress indices in response to accumulation of heavy metals within P. tetrastromatica could be used as molecular biomarkers in assessment and monitoring environmental quality of ecologically sensitive marine habitats.     

兰州市排污沟淤泥的有机质特征及来源分析

文章对兰州市西部工业区、生活区、医院等功能区的排污沟上、中、下段淤泥中饱和烃组成与分布特征进行了分析,初步认识了饱和烃的来源和组成特征。分析表明,排污沟淤泥中分布多种类型的饱和烃化合物,主要包括正构烷烃、无环类异戊二烯烷烃、萜类化合物、甾烷等。正构烷烃组成特征均为双峰态后峰型,主峰碳数为C15-C18和C25-C31。样品中检测出27种萜类化合物,其中五环萜类较三环萜类化合物占优势。甾烷化合物主要包括规则甾烷、重排甾烷、孕甾烷,以规则甾烷为主。有机质生物标志物参数表明,排污沟淤泥中有机质具有成熟和不成熟的特征,主要为现生植物、矿物油和化石燃料对烃类化合物的贡献,并且在不同区段由于外源有机物的加入而表现不同,有机质为多源混合来源。人类活动较集中的中段受矿物油和化石燃料燃烧污染程度明显比上游和下游严重。     

Common volatiles are major attractants for neonate larvae of the specialist flea beetle <Emphasis Type="Italic">Altica koreana</Emphasis> (Coleoptera: Chrysomelidae)

Olfactory stimuli play an important role in the host searching of larval phytophagous insects. Previous studies indicate that larvae that have to find feeding sites after hatching are generally attracted to host volatiles. However, there are few studies on the olfactory responses of neonate larvae to host volatiles in cases when those larvae hatched on the host plant. In the present study, we determined the olfactory responses of neonate larvae of the specialist flea beetle, Altica koreana Ogloblin, to host and six non-host plants, using a static-air "arena." Larvae responded significantly to the host plant Potentilla chinensis Ser. and five of six non-host plants, compared to the control. Larvae did not prefer the host plant over the non-host plants (except Artemisia sp.) when offered a choice. Additionally, odours of a non-host plant, which were unattractive to neonate larvae, may have masked the attractive odour of the host plant. These results indicate that common volatiles can play a major role in attracting larvae of this specialist to plants, but attraction to such odours may not be the major mechanism of host choice.     

复合垂直流人工湿地基质生化活性研究

文章测定了复合垂直流人工湿地基质生物膜生物量的空间分布、纤维素分解作用强度、氨化作用强度、酚分解作用强度、耗氧速率、厌氧活性等指标,结果表明:下行流池基质的纤维素分解作用、氨化作用、酚分解作用、耗氧速率等均高于上行流池,表层高于中下层,各指标变化趋势与生物膜生物量的空间分布存在明显的一致性;下行流池表层基质是污染物降解的主要空间;但上行流池基质的厌氧活性高于下行池;同时发现钴离子对基质厌氧微生物活性存在一定的影响,随着浓度的升高表现为先激活后降低。这些研究为阐明人工湿地净化机理提供了理论依据。