利用生物制剂处理北京动物园富营养型地表水的初步研究

北京市的地表水水质日益恶化，富营养化表现突出。目前改善水质、抑制藻类生长是解决富营养化水体的关键。试验采用从美国引进的新型生物制剂Eclean应用于北京动物园富营养化水体，试验结果表明，水体中的CODMn、总氮(TN)、总磷(TP)、浊度、叶绿素a、藻类浓度各项指标均有明显下降，水质明显改善，藻类生长基本得到控制。     

藻类光合作用对运河(杭州段)水质影响的初步研究

在河流水体自净规律的研究中,浮游藻类的生长状况是一个不可忽视的因素。通过藻类的生命活动,影响和改变水的理化性、透明度、颜色等。藻类通过光合作用,吸收水体中的 CO_2,同时释放出氧气,增加水体的溶解氧含量。反之,当藻类大量繁殖时,水体处于富营养化阶段,藻类的呼吸及残骸的分解,大量耗氧,又减少水体的溶解氧。这种对水体的充氧和耗氧明显影响水体的自净过程。另一方面,水体严重污染的环境,会影响藻类正常生长,因此研究运河藻类光合作用对水质的影响和改变浮游藻类的生长环境的可能,对研究运河水     

海藻提取物EClean生物工程技术处理富营养型地表水

以北京动物园的地表水为例,利用引进的海藻提取物EC lean生物工程技术对富营养化地表水进行处理试验研究。试验结果表明:应用此项技术有效降低了水体的浊度、COD和BOD5,水体脱氮降磷明显,藻类细胞密度下降,水体富营养化得到控制,减轻了“水华”藻类的危害。此技术在北京动物园富营养化水体的治理上表现出明显的应用效果。     

海藻提取物EClean生物工程技术处理富营养型地表水

以北京动物园的地表水为例，利用引进的海藻提取物EClean生物工程技术对富营养化地表水进行处理试验研究。试验结果表明：应用此项技术有效降低了水体的浊度、COD和BOD5，水体脱氮降磷明显，藻类细胞密度下降，水体富营养化得到控制，减轻了“水华”藻类的危害。此技术在北京动物园富营养化水体的治理上表现出明显的应用效果。     

草海底泥原位钝化工程示范及其生态环境效应

选取贵州草海重污染湖区,利用改性粘土钝化剂开展底泥原位钝化技术示范,对示范区内外主要水质参数、浮游生物和底栖动物等进行了对比监测与研究。结果表明:示范工程实施一年后钝化区水体氨氮(NH_3-N)和总磷(TP)含量分别降低至对照区的29%和23%,水体溶解氧含量达9 mg·L~(-1)以上,透明度显著增加;钝化区水体藻类总丰度降低40%以上,蓝藻所占比例大幅下降;钝化区沉水植物生长繁茂,水体自净功能明显增强,已形成草型清水生态系统。钝化区与对照区水体浮游动物、底栖水生生物种群及丰度无显著变化,表明钝化剂未对动物生长造成不良影响;原位钝化技术具有快速提升水体透明度和溶解氧含量、抑制底泥污染物释放、降低水体营养盐含量及抑制藻类生长等特点,且实施方便、成本低廉,在湖泊底泥污染治理和水体富营养化防治领域具有广阔应用前景。     

溶藻细菌对富营养化水体藻类群落结构的影响

向富营养化水体投放3株溶藻细菌(蜡状芽孢杆菌(Bacillus cereus)L7、L8和短小芽孢杆菌(Bacillus pumilus)L18)的菌液.在试验期内,3株溶藻细菌显示出很好的控藻效果,使叶绿素a(Chl-a)和藻类密度分别比初始值降低87%以上和72%以上;藻类Shannon-Weaver多样性指数维持在2～3,Pielous均匀度指数介于0.60～0.81,其中,溶藻细菌L7效果最明显.而未投加菌液的水体Chl-a未发生明显上升,但藻类密度自9.55×104个/mL上升到2.09×105个/mL,藻类Shannon-Weaver多样性指数由2.17降到1.11,Pielous均匀度由0.60降到0.33.3株溶藻细菌并非简单地杀灭水体中的全部或某些藻类,而是能明显地调节藻类群落结构,使其朝着较为稳定的方向发展,在修复藻型富营养化水体水生生态系统方面有很好的应用前景.     

小型景观湖水质模拟及应用研究

由于小型景观水体的体量和再生水补水措施的施行,其水质随环境和入水水质的变化和富营养化过程较大型水体快。由EFDC模型和WASP模型耦合建立小型浅水景观湖生态动力学模型,用实测水质数据进行参数率定与验证,可实现小型景观水体水质变化趋势的模拟,为水质管理提供决策支持。在此基础上,对民主湖在几种水质保障方案下1年的水质变化进行了模拟预测和对比,结果表明,作为富营养化程度表征的叶绿素a在空间和时间分布上均存在一定的规律性,夏季由于温度升高,叶绿素a浓度较高,说明藻类等浮游植物迅速增殖,是水质恶化水华暴发的高发期,而采取加大湖水水力循环和改善入口水质的控制方案,可使水质得到良好保障。     

富营养化水体的脱磷脱氮技术

水体中营养物含量的增加会导致藻类的大量繁殖,而藻类的呼吸作用以及死亡藻类的分解作用会导致水体的富营养化。富营养化水体与水体中氮和磷的含量密切相关,其中磷的作用特别重要。因此富营养化     

最大光能转化效率F_V/F_M用于城市人工水体藻华的监控预警

结合2012年5—10月对上海市区2个典型城市人工水体藻华过程叶绿素、最大光能转化效率FV/FM变化,及其与水质指标的关系,研究FV/FM用作城市人工水体藻华监控预警指标的可行性。结果表明,曲阳公园、黄兴公园的FV/FM分别在0.57~0.71和0.58~0.63之间;人工模拟昼夜日照和温度变化培养曲阳公园藻华的水藻得到,藻类生长适应期FV/FM<0.60,对数期FV/FM>0.60,FV/FM与藻类生物量无显著相关性,仅反映藻类所处生长阶段。分析FV/FM和叶绿素a与浊度、COD、TN、TP的相关性得到,FV/FM能兼顾藻类在富营养化水体中的生理环境和生长特性,综合反映了藻华在城市人工水体形成相关的物理、化学、生长特性等因素,对研究水体FV/FM=0.63可作为预警水体藻华发生的阈值。研究成果为城市人工水体藻华暴发的监控、预警提供新的途径和方法。     

扬水曝气技术在水源水质改善中的应用

扬水曝气技术是新开发的水质改善技术,用于混合上下水层、控制藻类生长、增加水体溶解氧、抑制底泥污染物释放.将该技术应用于某水源地,其提水效率达到同类设备--同温层曝气器的两倍;控制了水体表层的藻类数量,抑制了藻类的生长,将藻类叶绿素a含量降低了13.96%.扬水曝气技术的适用条件:用于控制藻类生长时,水深应不小于10 m;用于抑制底泥污染物释放时,水体应存在溶解氧小于1～2 mg/L的厌氧条件.     

Chloroaromatic pollutants in mussels incubated in two finnish watercourses polluted by industry

Concentrations of different chlorinated compounds were measured in mussels incubated in two polluted watercourses, a river (the River Kymijoki) and a lake (Lake Vanaja) for four weeks in summer 1995. The sum concentrations of polychlorinated phenols (PCP) and biphenyls (PCB) were both about 1 μg/g lipid weight (lw) in Lake Vanaja mussels, while in the River Kymijoki mussels PCPs were non-detectable and PCBs were measured 120 ng/g lIw. The concentrations of toxic polychlorinated dibenzo-p-dioxin (PCDD) and dibenzofuran (PCDF) congeners ranged between <17 and 370 pg/g Iw in Lake Vanaja mussels and between <38 and 11,000 pg/g lw in the River Kymijoki mussels. Polychlorinated diphenyl ethers (PCDE) were detected in the mussels incubated in the River Kymijoki (0.4–1.1 ng/g Iw), but not in those incubated in Lake Vanaja. Polychlorinated phenoxyanisoles (PCPA) were measured 33 ng/g lw and polychlorinated phenoxyphenols (PCPP) 300 ng/g lw in the mussels incubated in the River Kymijoki. PCPAs were also detected in reference samples, which were sediment and pike from the River Kymijoki and Baltic salmon, seal and white-tailed sea eagle.     

Book review

The Pesticide Manual ‐ A World Compendium, 8th Edition, C.R. Worthing, Editor and S.B. Walker, Assistant Editor, British Crop Protection Council, BCPC Publications Sales, Bear Farm, Binfield, Bracknell, Berkshire RG12 5QE, England. 1987, 1100 pp., UK £50; Overseas £56. ISBN 0–948404–01–9.     

Organochlorine compounds in a three-step terrestrial food chain

The concentrations of 15 organochlorine chemicals (PCBs and pesticides) were studied in a Central European oak wood food chain system: Great tit (Parus major), caterpillars (Tortrix viridana, Operophtera brumata, Erannis defoliaria), and oak-leaves (Quercus robur). Juvenile tits receive organochlorines from the mother via egg transfer and, eventually to a greater extent, from the caterpillar food source during nestling period. The concentrations of PCB 153 (2,2′,4,4′,5,5′-hexachlorobiphenyl, the most abundant in this study) was found in leaf material at ca. 1 ng/g, in caterpillars 10 ng/g, and in bird eggs 170 ng/g on an average and on a dry mass basis.     

The chemical stability of formulations of some hydrolyzable insecticides in aqueous mixtures with hydrolysis catalysts

Abstract

The active ingredients in commercial formulations of malathion, oxamyl, carbaryl, diazinon, and chlorpyrifos diluted to “spray tank”; concentrations with buffered distilled or natural water of pH 4–9 were stable for at least 24 hr. Formulations of trichlorfon were not stable at pH 7 or above but disappearance rates were slower than for the pure chemical in homogeneous solution. Cupric ion was observed to be an effective catalyst for the hydrolysis of a variety of pure organophosphorus insecticides but did not catalyze hydrolysis of the active ingredients of the formulations examined. Increasing the dilution of the formulation increased the susceptibility of malathion, oxamyl, and carbaryl to hydrolysis.     

Radionuclides in pinon pine (Pinus edulis) nuts from los alamos national laboratory lands and the dose from consumption

Abstract

One of the dominant tree species growing within and around the eastern portion of Los Alamos National Laboratory (LANL), Los Alamos, NM, lands is the pinon pine (Pinus edulis). Pinon pine is used for firewood, fence posts, and building materials and is a source of nuts for food—the seeds are consumed by a wide variety of animals and are also gathered by people in the area and eaten raw or roasted. This study investigated the (1) concentration of ³H, ¹³⁷Cs, ⁹⁰Sr, ^totU, ²³⁸Pu, ^{239, 240}Pu, and²⁴¹ Am in soils (0‐ to 12‐in. [31 cm] depth underneath the tree), pinon pine shoots (PPS), and pinon pine nuts (PPN) collected from LANL lands and regional background (BG) locations, (2) committed effective dose equivalent (CEDE) from the ingestion of nuts, and (3) soil to PPS to PPN concentration ratios (CRs). Most radionuclides, with the exception of ³H in soils, were not significantly higher (p < 0.10) in soils, PPS, and PPN collected from LANL as compared to BG locations, and concentrations of most radionuclides in PPN from LANL have decreased over time. The maximum net CEDE (the CEDE plus two sigma minus BG) at the most conservative ingestion rate (10 lb [4.5 kg]) was 0.0018 mrem (0.018 μSv); this is far below the International Commission on Radiological Protection (all pathway) permissible dose limit of 100 mrem (1000 μSv). Soil‐to‐nut CRs for most radionuclides were within the range of default values in the literature for common fruits and vegetables.     

Degradation and sorption of imidacloprid in dissimilar surface and subsurface soils

Degradation and sorption/desorption are important processes affecting the leaching of pesticides through soil. This research characterized the degradation and sorption of imidacloprid (1-[(6-chloro-3-pyridinyl)-methyl]-N-nitro-2-imidazolidinimine) in Drummer (silty clay loam) and Exeter (sandy loam) surface soils and their corresponding subsurface soils using sequential extraction methods over 400 days. By the end of the incubation, approximately 55% of imidacloprid applied at a rate of 1.0 mg kg^?1 degraded in the Exeter sandy loam surface and subsurface soils, compared to 40% of applied imidacloprid within 300 days in Drummer surface and subsurface soils. At the 0.1 mg kg^?1 application rate, dissipation was slower for all four soils. Water-extractable imidacloprid in Exeter surface soil decreased from 98% of applied at day 1 to > 70% of the imidacloprid remaining after 400 d, as compared to 55% in the Drummer surface soil at day 1 and 12% at day 400. These data suggest that imidacloprid was bioavailable to degrading soil microorganisms and sorption/desorption was not the limiting factor for biodegradation. In subsurface soils > 40% of ¹⁴C-benzoic acid was mineralized over 21 days, demonstrating an active microbial community. In contrast, cumulative ¹⁴CO₂ was less than 1.5% of applied ¹⁴C-imidacloprid in all soils over 400 d. Qualitative differences in the microbial communities appear to limit the degradation of imidacloprid in the subsurface soils.     

Biochemical interaction of six op delayed neurotoxicants with several neurotargets

Abstract

Five organophosphorous insecticides: Leptophos, EPN, Cyano‐fenphos, trichloronate and salithion proved to cause irreversible ataxia not only to chicken but also to mice and sheep. TOCP was included as a reference. Cyanofenphos blocked the catecholamine B‐receptor binding activity with ³H‐norepinephrine at a level similar to that of the specific inhibitor propranolol in the mouse heart preparation. In the lamb heart preparation, the B‐receptor was more sensitive to Leptophos, salithion and TOCP than to propranolol. The six compounds and their oxons were screened for their in‐vitro inhibition to monamine oxidase (MAO), acetyl cholinesterase (AChE) and neurotoxic esterase (NTE) in the brain of either mouse, lamb or chicken. It is believed that their AChE inhibition stands for their acute toxicity, while NTE inhibition is responsible for their paralytic ataxia.     

土壤中砷的化学平衡

本文比较详细地综述了砷的化学特性,环境背景值及来源和循环,土壤中砷的三大化学平衡即沉淀溶解平衡,氧化还原平衡,吸附解吸平衡,以及微生物对砷的转化。     

Elemental uptake by edible herbs and lettuce (Latuca sativa)

The total concentration of toxic elements (aluminum, cadmium, chromium and lead) and selected macro and micro elements (iron, manganese, copper and zinc) are reported in six leafy edible vegetation species, namely lettuce, spinach, cabbage, chards and green and red types of Amaranth herbs. Although spinach and chards had greater than 125 mv of iron, both the amaranthus herbs recorded > than 320 μ g g^{? 1} dry weight. In both the spinach and chard species, the Mn and Zn levels were appreciable recording > 225 μ g g^{? 1} and 150 μ g g^{? 1} dry weight, respectively. Aluminum concentrations were (in μ g g^{? 1} dry weight) lettuce (10), cabbage (11), spinach (167), chards (65), amaranthus green (293) and amaranthus red (233). All the micro and macro elements and the toxic elements (Ni, Cr, Cd and Pb) elements analyzed, were below the recommended maximum permitted levels (RMI) in vegetables. Further the elemental uptake and distribution of the nine elements, at three growth stages of the lettuce plant grown on soil bed under controlled conditions are detailed. In the soil, except for iron (16%), greater than 33% of the other cations were in exchangeable form. Generally in the lettuce plant, roots retained much of the iron (> 224 μ g g^{? 1}) and aluminum (> 360 μ g g^{? 1}), while leaves had less than 200 μ g g^{? 1} of iron and 165 μ g g^{? 1} of Al. Although the concentrations of elements marginally decreased with growth, the lettuce leaves had significant amounts of Mn (30 μ g g^{? 1}), Zn (50 μ g g^{? 1}) and Cu (3.6 μ g g^{? 1}). Some presence of lead in leaves (2.0 μ g g^{? 1}) was noticed, but all the toxic and other elements analyzed were well below the RMI values for the vegetables.     

The dissipation of nonlyphenol in stream and pond water under simulated field conditions

Abstract

The dissipation of 1.0 ppm nonylphenol in stream and pond water, incubated in flasks at 16°C under simulated field conditions up to 44 days indicated that the half‐life was 2.5 days if the flasks were open, and 16 days if they were closed. A transformed product was detected in the closed flasks.

Translocation of nonylphenol in water occurred when treated water samples were incubated in the presence of sediment. After 10 days, nonylphenol was detected only in the sediment, but not in water (detection limit = 10 ppb). About 80% of the nonylphenol was degraded in 71 days, but no degradation occurred if the water and the sediment were autoclaved prior to incubation.