Biotic Ligand Model的简化模型及预测性能评价

通过检索4物种(Fathead minnow、D.magna、D.pulex、Rainbow trout)在地表水中实测的铜半致死浓度(Observed_LC50),及Biotic Ligand Model(BLM)预测其半致死浓度(Predicted_LC50),得到4物种的预测精度依次为0.075、0.52、0.96、0.29,模型对Fathead minnow与Rainbow trout的预测性能较差.在此基础上,分析显示预测误差值与LA50呈指数关系,表明LA50值并非常数值.通过对BLM的LA50的校正,Fathead minnow与Rainbow trout的预测精度升为0.59、0.42.通过分析LA50与硬度的关系,发现BLM在软水环境中预测效果较差.另外,随机均匀生成500组水质参数组,通过BLM预测,筛选出4项敏感参数为DOC、pH、HCO-3浓度及温度,并建立相应物种的LC50与其的多元线性关系,大大简化了生物配位模型.     

GeoChip-based analysis of the microbial community functional structures in simultaneous desulfurization and denitrification process

The elemental sulfur （S^0） recover）, was evaluated in the presence of hi,ate in two development models of simultaneous desulfurization and denitrification （SDD） process. At the loading rates of 0.9 kg S/（m^3.day） for sulfide and 0.4 kg N/（m^3.day） for nitrate, SO conversion rate was 91.1% in denitrifying sulfide removal （DSR） model which was higher than in integrated simultaneous desulfurization and denitrification （ISDD） model （25.6%）. A comprehensive analysis of functional diversity, structure and metabolic potential of microbial communities was examined in two models by using functional gene array （GeoChip 2.0）. GeoChip data indicated that diversity indices, community structure, and abundance of functional genes were distinct between two models. Diversity indices （Simpson＇s diversity index （1/D） and Shannon-Weaver index （H′）） of all detected genes showed that with elevated infiuent loading rate, the functional diversity decreased in ISDD model but increased in DSR model. In contrast to ISDD model, the overall abundance of dsr genes was lower in DSR model, while some functional genes targeting from nitrate-reducing sulfide-oxidizingbacteria {NR-SOB）, such as Thiobacillus denitrficans, Sulfurimonas denitrificans, and Paracoccus pantotrophus were more abundant in DSR model which were highly associated with the change of SO conversion rate obtained in two models. The results obtained in this study provide additional insights into the microbial metabolic mechanisms involved in ISDD and DSR models, which in turn will improve the overall performance of SDD process.     

A comparison on the phytoremediation ability of triazophos by different macrophytes

The strategy of choosing suitable plants should receive great performance in phytoremediation of surface water polluted by triazophos(O,O-diethyl-O-(1-phenyl-1,2,4-triazol-3-base) sulfur phosphate, TAP), which is an organophosphorus pesticide widespread applied for agriculture in China and moderately toxic to higher animal and fish. The tolerance, uptake, transformation and removal of TAP by twelve species of macrophytes were examined in a hydroponic system and a comprehensive score(CS) of five parameters(relative growth rate(RGR), biomass, root/shoot ratio, removal capacity(RC), and bio-concentration factor(BCF)) by factor analysis was employed to screen the potential macrophyte species for TAP phytoremediation. The results showed that Thalia dealbata, Cyperus alternifolius, Canna indica and Acorus calamus had higher RGR values, indicating these four species having stronger growth capacity under TAP stress. The higher RC loading in Iris pseudacorus and Cyperus rotundus were 42.11 and 24.63 μg/(g fw·day), respectively. The highest values of BCF occurred in A. calamus(1.17), and TF occurred in Eichhornia crassipes(2.14). Biomass and root/shoot ratio of plant showed significant positive correlation with first-order kinetic constant of TAP removal in the hydroponic system, indicating that plant biomass and root system play important roles in remediation of TAP. Five plant species including C. alternifolius, A. calamus, T. dealbata, C. indica and Typha orientalis, which owned higher CS, would be potential species for TAP phytoremediation of contaminated water bodies.     

水绵、光照、密度对入侵植物喜旱莲子草生长的影响

对喜旱莲子草在不同光照、密度及有无水绵组合条件下的可塑性进行了研究。结果表明水绵的存在抑制了喜旱莲子草的生长,但由于光照和密度的作用弱化了水绵对喜旱莲子草的抑制作用。在有水绵"低光照"中密度条件下,喜旱莲子草的生物量指标和形态指标是所有处理中最大的。在一定程度上说明低光照、中密度增强了喜旱莲子草的入侵性。     

气候变化对海洋生物资源的影响及其应对之策

正全球气候变化已经成为全世界关注环境问题的焦点,海洋生物资源的保护也越来越受到人们的重视。然而,近年来,由于全球气候变化的加剧,无论是全球变暖所引起的海平面上升、海洋酸化、海洋生物大批量的生病和死亡、海洋外来物种入侵、物种遗传多样性降低,还是自然灾害的日益频繁发生,都对世界渔业资源产生极大的影响。为此,人类迫切需要采取恰当的措施以拯救不堪负荷的世界渔业资源和应对不利的气候变化给海洋生物资源带来的负面影响。     

辽东湾西侧六股河口附近滨海地区海水入侵与土壤盐渍化特征

根据现场监测资料,对辽东湾西侧绥中砂质平原土壤盐渍化特征进行了分析。监测区含水层主要是由较粗的透水性较好砂砾石等粗颗粒物质组成,由于地下水的过度开采,海水入侵严重,海水入侵带入的可溶性盐在土层中积蓄,使土层产生不同程度的盐渍化,其盐渍化最显著的地段在大渔场(SL1孔)区段,距海岸最近;受季节性降水的影响,盐渍化的类型和分布也不同,平水期主要是硫酸盐-氯化物型的轻盐渍化土,主要集中在1.5 m层位;丰水期土壤盐渍化较轻,在1.5 m处有氯化物型轻盐渍化土分布,各离子含量明显降低,HCO-3含量高,Cl-含量最低;枯水期分布层位主要在2.0 m以下,主要是硫酸盐-氯化物型和氯化物型中盐渍化土,各离子含量从表层向下部增高,阴离子HCO-3含量最高,Na+与HCO-3曲线分布较一致。     

磁性污泥基活性炭催化臭氧氧化去除布洛芬的研究

采用浸渍法制备了不同金属掺杂的磁性污泥活性炭(MSAC),考察了掺杂金属种类、催化剂和臭氧投量对MSAC催化臭氧氧化去除布洛芬(IBP)效能的影响,并通过测定活性物种含量研究了反应机制。结果表明,锰掺杂MSAC的催化活性最高,当臭氧和催化剂投量分别为1.0 mg/L和50.0 mg/L时,IBP的去除率为86.2%,比单独臭氧氧化工艺高28.3%。当催化剂投量由50.0 mg/L增加至100.0 mg/L时,IBP的去除率仅增加了2.3%;当臭氧投量由1.0 mg/L增加至3.0 mg/L时,IBP去除率由86.2%增加至99.7%。叔丁醇的加入显著降低了IBP去除率,活性物种定量分析结果进一步证实了IBP的快速去除主要是由于羟基自由基(·OH)的作用,过氧化氢在·OH产生过程中起引发剂作用。