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1.
为保护浙江绍兴鉴湖水域水质,由浙江省科委立项研究的《鉴湖环境容量及水质规划》课题,经三年多的工作,业已由绍兴市环境保护科学研究所等四单位研究完成。并于1992年6月25日在绍兴由省环保局主持通过了鉴定。该项目在分析了水域自然环境特征及当前存在的主要环境问题基础上,进行了鉴湖水质现状、污染源调查及发展趋势预测,水域水量及污染物平衡计算。运用入湖污染物与水质关系的数学模型对该水域主要  相似文献   

2.
以天津临港生态湿地公园人工湖水质和水文的调查数据为依据,运用相关性分析和聚类分析将研究水体划分为3类水域。研究了不同聚类水域水温、DO、p H、氮磷营养元素以及Chla的时空分布特征。结果显示,DO、硝态氮、TN、TP与流速呈显著正相关,水温、SS与流速呈显著负相关。Chla与水深呈显著正相关,TN、硝态氮与水深呈显著负相关。断面宽度与所有理化指标均没有显著相关性。3种水域在监测期间N/P比(TN/TP)显示湖泊正在从氮营养元素限制型(N/P7)向适宜藻类生长的营养类型过渡。富营养化评价显示,再生水为补水的临港人工湖在监测期间水质已处于中度富营养,主要贡献因子为COD和TP。  相似文献   

3.
芬兰是北欧的一个多湖国家,全境有大小湖泊六万多个,水系纵横,内陆水域占全国总面积百分之九以上。芬兰又是一个森林之国,森林复盖面积达百分之七十八。利用森林资源,芬兰大力发展造纸及木材加工等工业,由此也引起水质污染问题。为了保护水源,芬兰国家水源局从1972年开始研究发展水质自动监测技术。1975年,世界银行向芬兰贷款两千万美元,用于水质保护科学研究,其中主要研究项目就是建立水质自动监测系统。从1974年至1980年,芬兰水源局水质研究所先后在中部及南部Kokemaeiljoki和Kymijoki河系上建立自动水质监测站、网,目的是监测和防止工业废水、废料、城市污水向水系排放,并研究水质变化规律。经过几年的运行和改进,取得了较好的效果,积累了一定的经验。  相似文献   

4.
水是生命之源、生产之要、生态之基.近30年来,随着经济社会的快速发展和城市化、工业化演进,我国河流水环境与水生态问题引起各界高度重视[1].2018年6月,《中共中央国务院关于全面加强生态环境保护坚决打好污染防治攻坚战的意见》[2]指出,要全面加强生态环境保护,提升生态文明,建设美丽中国,部署实施蓝天、碧水、净土三大保卫战.至2020年底,污染防治攻坚战阶段性目标任务已顺利完成,生态环境质量明显改善.据统计,2020年全国地表水优良水质断面比例由2015年的66%上升到83.4%,超过"十三五"目标值13.4%;劣V类水体比例由9.7%下降到0.6%,超过"十三五"目标值4.4%;长江干流全部实现Ⅱ类及以上水质[34].在水质全面提升改善的基础上,"十四五"期间,水环境治理由水环境质量改善向"水资源、水环境、水生态"三水统筹转变,坚持污染减排和生态扩容两手发力,推进"美丽河湖"保护与建设.河流生态缓冲带是河流生态系统的重要载体,具有保护河流生物多样性、减少陆域污染物入河、提高水体自净能力以及阻隔人类生产生活活动的直接干扰等生态功能,因而开展河流生态缓冲带构建、保护修复是"十四五"流域水生态环境保护的重点工作[5-6].  相似文献   

5.
洪泽湖水域的环境演变遥感分析   总被引:1,自引:0,他引:1  
针对传统水质监测的定点、定剖面采样分析时间及空间的局限性,为对湖泊水质进行全面系统的分析,在前人研究工作的基础上,建立了一种水域水质状况图像识别的主成分监督分类方法,通过对洪泽湖湖区的1991年12月15日和2000年1月7日,两个时相TM遥感图像数据,分别进行主成分变换,并依据不同类型水体的光学特性,分析各主成分图像的构成及其环境意义。研究表明:洪泽湖湖区的水质分布,具有从西向东,从北向南由清洁水(优)向一般水依次递减、逐年下降的特征。其清洁水体主要分布于洪泽湖西部的溧河洼、临淮头、西北部的安河洼和成子湖的北部。从1991--2000年,洪泽湖入湖的工业废水及生活污水量有所减少,湖水受污染程度明显减轻,相对“八五”期间水质污染日益加重的现象,“九五”以后水质逐渐改善。将其分类结果与所收集的洪泽湖历年水质资料对比分析表明:主成分监督分类结果与环境要素吻合较好,且基本反映了其水质环境的变化趋势。  相似文献   

6.
在以再生水为补水水源的圆明园玉玲珑水域进行沉水植物收割实验,自2011年4—12月间每隔半个月监测一次水质。结果表明,通过在生长期收割沉水植物,玉玲珑水体TP、SRP、TN、NH4+-N、NO3--N和COD的平均浓度可维持在0.1、0.04、0.86、0.1、0.32和18 mg/L左右,水质保持在Ⅲ类至Ⅳ类地表水之间;与之对照的不收割沉水植物的玉玲珑进水口水域,9月沉水植物开始死亡腐烂,TP、SRP、TN、NH4+-N最高分别可达0.5、0.1、2.4和0.60 mg/L;作为对照的另一以挺水植物为主的水域,水质普遍劣于有大量沉水植物生长的水域,TP、SRP、TN、NH4+-N最高分别可达1.2、0.60、6.1和0.61mg/L。圆明园的实地实验表明,沉水植物有很强的净化水质作用,通过生长期收割,能够进一步强化其水质净化作用,可以作为一项对富营养化水体进行生态管理的有效措施进行推广。  相似文献   

7.
一、前言 目前国际上水环境保护战略正在从水经济工程战略(即“谁污染谁治理”等环保方针政策)向水环境生态战略(即以资源开发为起点,调节控制物质循环中的污染源,综合协调社会经济和环境生态的平衡,确保其永续的同步发展)过渡.其主要标志是:美国的河系水质规划和环境影响评价;日本的  相似文献   

8.
在广州市南沙区水域采集地表水和水生生物样品,对水质主要理化指标、叶绿素a含量和初级生产力以及水生生物(浮游植物和浮游动物)的种类、数量、多样性和均匀度指数等进行调查,综合评价了南沙区水域水生生态环境质量.结果表明,利用不同指标对南沙区水域进行评价获得的结果基本一致,介于贫营养化至中营养化状态之间,水生生态环境质量状况较好.  相似文献   

9.
EM对地面水域水质的净化   总被引:1,自引:0,他引:1  
试验研究了EM对地面水域水质的净化作用,探讨了EM投放方式对水质的净化效果以及对地面水域水质指标的净化选择性及其净化的经济可行性。  相似文献   

10.
经济的高速发展不只是为社会带来了便利,也无形中增加了水资源消耗的速率与水环境污染的负担。自“十三五”以来,为提高断面水环境质量、提升整体水质环境,各省市相继出台了水环境提升、水污染防治以及生态补偿政策。南京市江宁区顺应中央要求并结合自身特点,积极制定并实施了断面生态补偿工作方案,建立了由考核指标、补偿方式、核算方法、补偿标准组成的成套断面生态补偿考核系统。明确了补偿标准机制、补偿责任分配以及补偿资金使用等关键问题。为推进江宁区断面水质达标工作与水环境提升的总体目标奠定了夯实的基础。  相似文献   

11.
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.  相似文献   

12.
We reported previously that trichodiene, a volatile trichothecene derivative, was produced by a Stachybotrys isolate, also known to produce highly cytotoxic, non-volatile, macrocyclic trichothecenes (satrotoxins). We investigated the relationship between the production of trichodiene and various non-volatile trichothecenes for several molds. Volatile metabolites were concentrated by adsorption on Tenax TA and analyzed by GC/MS, while non-volatile metabolites were separated by HPLC, derivatized and analyzed by GC/MS. Stachybotrys chartarum isolates producing macrocyclic trichothecenes secreted significantly larger amounts of trichodiene and other sesquiterpenes than isolates which only produced simple trichothecenes. The amounts of secreted trichodiene were relatively small in all cases. With the exception of Memnoniella, which excreted small amounts of sesquiterpenes, the other isolates produced varying amounts of sesquiterpenes, including trichodiene, as well as simple tricothecenes, no detectable trichodiene, but large amounts of griseofulvin derivatives. In Stachybotrys there is apparently a correlation between trichodiene and macrocyclic trichothecene production. In the remaining isolates, there was no simple relationship between trichodiene and non-volatile trichothecene synthesis. Trichodiene is produced in larger amounts by Stachybotrys isolates, which also produce satratoxins, but it will be difficult to utilize this metabolite to detect toxic isolates in buildings due to the relatively small amounts excreted.  相似文献   

13.
The ability of two biodegradable surfactants, polyoxyethylene (20) sorbitan monooleate (Tween 80) and sodium dihexyl sulfosuccinate (Aerosol MA), to recover a representative dense non-aqueous-phase liquid (DNAPL), trichloroethene (TCE), from heterogeneous porous media was evaluated through a combination of batch and aquifer cell experiments. An aqueous solution containing 3.3% Aerosol MA, 8% 2-propanol and 6 g/l CaCl(2) yielded a weight solubilization ratio (WSR) of 1.21 g TCE/g surfactant, with a corresponding liquid-liquid interfacial tension (IFT) of 0.19 dyn/cm. Flushing of aquifer cells containing a TCE-DNAPL source zone with approximately two pore volumes of the AMA formulation resulted in substantial (>30%) mobilization of TCE-DNAPL. However, a TCE mass recovery of 81% was achieved when the aqueous-phase flow rate was sufficient to displace the mobile TCE-DNAPL toward the effluent well. Aqueous solutions of Tween 80 exhibited a greater capacity to solubilize TCE (WSR=1.74 g TCE/g surfactant) and exerted markedly less reduction in IFT (10.4 dyn/cm). These data contradict an accepted empirical correlation used to estimate IFT values from solubilization capacity, and indicate a unique capacity of T80 to form concentrated TCE emulsions. Flushing of aquifer cells with less than 2.5 pore volumes of a 4% T80 solution achieved TCE mass recoveries ranging from 66 to 85%, with only slight TCE-DNAPL mobilization (<5%) occurring when the total trapping number exceeded 2 x 10(-5). These findings demonstrate the ability of Tween 80 and Aerosol MA solutions to efficiently recover TCE from a heterogeneous DNAPL source zone, and the utility of the total trapping number as a design parameter for a priori prediction of DNAPL mobilization and bank angle formation when flushing with low-IFT solutions. Given their potential to stimulate microbial reductive dechlorination at low concentrations, these surfactants are well-suited for remedial action plans that couple aggressive mass removal followed by enhanced bioremediation to treat chlorinated solvent source zones.  相似文献   

14.
Abstract

The pH‐disappearance rate profiles were determined at ca. 25°C for 24 insecticides at 4 or 5 pH values over the range 4.5 to 8.0 in sterile phosphate buffers prepared in water‐ethanol (99: 1 v/v). Half‐lives measured at pH 8 were generally smaller than at lower pH values. Changes in half lives between pH 8.0 and 4.5 were largest (>1000x) for the aryl carbamates, carbofuran and carbaryl, the oxime carbamate, oxamyl, and the organophosphorus insecticide, trichlorfon. In contrast, half lives of phorate, terbufos, heptachlor, fensulfothion and aldicarb were affected only slightly by pH changes. Under the experimental conditions described half lives at pH8 varied from 1–2 days for trichlorfon and oxamyl to >1 year for fensulfothion and cyper‐methrin. Insecticide persistence on alumina (acid, neutral and basic), mineral soils amended with aluminum sulfate or calcium hydroxide to different pH values and four natural soils of different pH was examined. No correlation was observed between the measured pH of these solids and the rate of disappearance of selected insecticides applied to them. These observations demonstrate the difficulty of extrapolating the pH dependent disappearance behaviour observed in homogeneous solution to partially solid heterogeneous systems such as soil.  相似文献   

15.
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.  相似文献   

16.
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.  相似文献   

17.
Organochlorine compounds in a three-step terrestrial food chain   总被引:1,自引:0,他引:1  
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.  相似文献   

18.
The occurrence of particle associated PAH and other mutagenic PAC was determined in 1996 in the street air of Copenhagen. In addition, particle extracts were tested for mutagenicity. The measurements were compared with previous measurements in 1992/1993. The levels had decreased in this period. The decrease was caused by an implementation of light diesel fuels for buses and the exchange of older petrol-driven passenger cars with catalystequipped new ones. About 65% of the reduction was caused by the application of the light diesel fuels. Under special conditions, chemical processes in the atmosphere produced many more mutagens than the direct emissions. The concentrations of S-PAC and N-PAC were 10 times lower than those of PAH, while the levels of oxy-PAH were in the same order of magnitude as those of PAH. Benzanthrone, an oxy-PAH, is proposed to be formed in the atmosphere in addition to direct emissions. Benzo(a)pyrene, often applied as an air quality criteria indicator, was photochemically degraded in the atmosphere. A strong increase in the mutagenic activities was observed to coincide with a depletion of benzo(a)pyrene.  相似文献   

19.
20.
Approximately 25, 000-35, 000 dry cleaning facilities currently operate in the U.S. The release of perchloroethylene and other solvents from these establishments represents a major source of soil and groundwater contamination. The manner in which dry cleaning solvents escape from dry cleaning plants is, for all practical purposes, identical for chlorinated and petroleum hydrocarbon solvents and is related to one of the following events: the catastrophic failure of a component of the dry cleaning system, the improper installation, operation or maintenance of the dry cleaning equipment or a combination of all of these causes. Acceptable customs, codes and regulations can also dictate what is authorized for operation of a dry cleaning facility in a particular community, geographic area during a particular time frame. Environmental litigation dealing with the origin of a solvent release from dry cleaners tends to focus on the design and manufacture of dry cleaning industry machines such as washers, washer extractors, tumblers, solvent filters, water separators, stills and spotting boards. A thorough analysis of the daily operations of dry cleaners often reveals that poor maintenance, failure to follow the manufacturer's instructions and the actions of the operator are the most likely causes of soil and groundwater pollution. In order to forensically evaluate the most probable origins of a solvent release and to examine issues regarding liability, a thorough understanding of the history of dry cleaning and a detailed analysis of the operation and maintenance of the dry cleaning equipment are necessary. The discovery of solvent plumes in the vicinity of dry cleaning plants may suggest that the solvent source is the dry cleaning plant; however, the presence of these plumes does not necessarily indicate that the dry cleaning equipment was defectively designed or manufactured. A thorough review of the type of equipment used over the life of the dry cleaning plant and verifiable solvent mileage records frequently indicates that operators of the plant have disposed of solvent and contaminated solids into the municipal sewer or on ground surfaces.  相似文献   

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