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1.
顺义区地下水水源地脆弱性评价   总被引:4,自引:0,他引:4  
从顺义区地下水源地的特点和实际情况出发,建立了顺义区地下水源地脆弱性综合评价指标体系,并基于该指标体系采用灰关联度评价方法对顺义区地下水源地进行脆弱性综合评价。将综合评价与固有脆弱性评价对比分析,结果表明,采用地下水水源地综合脆弱性与固有脆弱性相结合的评价方法评价结果更为科学合理,可以更好地评价顺义区地下水源地脆弱性。  相似文献   

2.
模糊物元识别模型在巢湖水体富营养化评价中的应用研究   总被引:9,自引:1,他引:8  
选取TN、TP、Chl-a、COD、BOD5、DO和SD等7项指标,应用模糊物元识别模型对2000~2007年巢湖的12个水质监测点的富营养化等级进行了模糊识别。通过与巢湖同期水质浓度变化及其分布区域进行对比分析,验证了模糊物元识别模型在巢湖水体富营养化评价中的适用性。巢湖富营养化评价结果表明,2000~2007年富营养化呈逐年加重的趋势,据采样点模糊物元计算结果得知西巢湖(1#~6#)的富营养化状况比东巢湖(7#~12#)更严重,西巢湖贴近度最高值为0.9974,接近极富营养状态,而东巢湖的最高值仅为0.5866。从年际变化上看,2000~2007年东巢湖富营养化状况变化不大,营养状态级处在较低的水平,而西巢湖的富营养状况变化则较大,营养状态级则处在较高水平。  相似文献   

3.
基于模糊评价原理,选取氨氮、总磷、高锰酸盐指数、溶解氧、五日生化需氧量和总氮等6项评价指标构造综合评判数学模型,通过改进模糊评价结果分析方法,运用加权平均原则对模糊评价结果向量进行计算,综合分析和评价太湖20个监测点位2011—2013三年的水质情况。最后运用Arc GIS的空间分析功能,选取合理的插值方法,对评价结果进行空间分析,与传统的模糊评价分析方法相比,所得评价结果更能直观反映湖体真实的水质状况。结果表明,时间上,太湖水质2012年比2011年有所好转,而2013年水质又有所下降;空间上,太湖呈现出从西到东水质状况逐渐变好的趋势;总体来说,水质评价结果不容乐观,仍需进一步控制污染物的浓度。  相似文献   

4.
苯污染地下水系统更硝化菌分布及其净化过程   总被引:2,自引:0,他引:2  
生物降解作用是地下水系统有机污染物自然衰减过程中最重要的破坏性衰减机制。在分析中,以我国某受苯污染水源地的地下水系统为对象,研究了该地下水中反硝化菌的分布,筛选出2株土著反硝化菌,通过生物降解实验证明其具有降解苯的能力,同时结合水源地历年的水质监测数据,首次从地球化学及生物学2个方面说明了该地下水中存在反硝化菌对苯的生物净化作用,为进一步研究该地下水中苯自然衰减规律奠定基础。  相似文献   

5.
桂烈勇 《污染防治技术》2007,20(1):63-66,80
根据太仓市饮用水地表水源和地下水的监测数据,分别采用单因子评价和综合评价方法,对饮用水源的水质进行评价。结果认为地表水水源已受到轻度污染,属Ⅲ类水;地下水的水质较差,已不适合于直接饮用。饮用水水源的主要污染物为COD、氨氮、挥发酚、硝酸盐氮和高锰酸盐指数。对饮用水水源的污染成因进行了全面分析,并从四个方面提出了水源安全保护对策:法律法规与行政手段、技术支撑、经济支持和宣传教育.  相似文献   

6.
杭州市区地下水质量评价   总被引:2,自引:0,他引:2  
采用综合评分法对杭州市区及近郊各类型地下水1997年的水质监测结果进行科学评价,为有关部门科学管理和合理开发利用地下水资源提供决策依据。  相似文献   

7.
在金坛市水源现状分析的基础上,指出了饮用水源存在的问题,并对长荡湖水源进行了水质的现状评价和预测分析,建议长荡湖作为备用水源地,对长荡湖水源地保护区的划分提出了具体方案。最后提出了加强水源地的生态建没、环境风险应急预案和水资源管理体系建设等的水源地保护一系列方案。  相似文献   

8.
苯污染地下水系统反硝化菌分布及其净化过程   总被引:2,自引:0,他引:2  
生物降解作用是地下水系统有机污染物自然衰减过程中最重要的破坏性衰减机制。在分析中,以我国某受苯污染水源地的地下水系统为对象,研究了该地下水中反硝化菌的分布,筛选出2株土著反硝化菌,通过生物降解实验证明其具有降解苯的能力,同时结合水源地历年的水质监测数据,首次从地球化学及生物学2个方面说明了该地下水中存在反硝化菌对苯的生物净化作用,为进一步研究该地下水中苯自然衰减规律奠定基础。  相似文献   

9.
水质评价作为合理开发和保护水资源的一项重要工作,越来越受到人们重视。传统的模糊综合水质评价方法因未考虑到水质指标权重的季节变化而可能影响评价结果,故对水质指标权重向量进行了改进,提出了时域权重矩阵的概念,并将实测权重向量与时域权重矩阵相结合,进行组合赋权,得到综合权重向量。应用改进的模糊综合评价方法对某引水明渠水质进行综合评价,结果相比于传统模糊综合水质评价法更符合实际。  相似文献   

10.
对三峡库区受回水影响的42个城镇饮用水源地水质进行调查研究,运用美国环境保护署推荐的健康风险评价模型对水源地水体中化学污染物质的健康风险作了初步评价。结果显示:研究区域致癌物的致癌风险偏高,三江水源地总致癌风险1.22×10~(-6)~7.19×10~(-5) a~(-1),支流水源地总致癌风险1.50×10~(-6)~7.19×10~(-5) a~(-1),地下水水源地总致癌风险3.05×10~(-6)~7.19×10~(-5)a~(-1),3种类型水源人均年致癌风险接近或超过了瑞典环境保护署、荷兰建设和环境署、英国皇家协会及国际放射防护委员会(ICRP)推荐的最大可接受风险水平,水源地类型的致癌风险顺序为地下水支流三江水库;非致癌物的总致癌风险均小于或略超过荷兰建设和环境署推荐的可忽略风险水平(10-8 a-1)。因此,认为12种非致癌物通过饮用水途径引起的风险是可以接受的,其总致癌风险处于Ⅲ级、中风险状态。与全国其他区域相比,15种参评因子所占总致癌风险值比例大致相同。  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.
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   

13.
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   

14.
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   

15.
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   

16.
Abstract

The purpose of this study was to determine radionuclide and trace element concentrations in bottom‐feeding fish (catfish, carp, and suckers) collected from the confluences of some of the major canyons that cross Los Alamos National Laboratory (LANL) lands with the Rio Grande (RG) and the potential radiological doses from the ingestion of these fish. Samples of muscle and bone (and viscera in some cases) were analyzed for 3H, 90Sr, 137Cs, totU, 238Pu, 239,240Pu, and 241Am and Ag, As, Ba, Be, Cr, Cd, Cu, Hg, Ni, Pb, Sb, Se, and Tl. Most radionuclides, with the exception of 90Sr, in the muscle plus bone portions of fish collected from LANL canyons/RG were not significantly (p<0.05) higher from fish collected upstream (San Ildefonso/background) of LANL. Strontium‐90 in fish muscle plus bone tissue significantly (p<0.05) increases in concentration starting from Los Alamos Canyon, the most upstream confluence (fish contained 3.4E‐02 pCi g‐1 [126E‐02 Bq kg‐1]), to Frijoles Canyon, the most downstream confluence (fish contained 14E‐02 pCi g‐1 [518E‐02 Bq kg‐1]). The differences in 90Sr concentrations in fish collected downstream and upstream (background) of LANL, however, were very small. Based on the average concentrations (±2SD) of radionuclides in fish tissue from the four LANL confluences, the committed effective dose equivalent from the ingestion of 46 lb (21 kg) (maximum ingestion rate per person per year) of fish muscle plus bone, after the subtraction of background, was 0.1 ± 0.1 mrem y‐1 (1.0 ± 1.0 μSv y‐1), and was far below the International Commission on Radiological Protection (all pathway) permissible dose limit of 100 mrem y‐1 (1000 μSv y‐1). Of the trace elements that were found above the limits of detection (Ba, Cu, and Hg) in fish muscle collected from the confluences of canyons that cross LANL and the RG, none were in significantly higher (p<0.05) concentrations than in muscle of fish collected from background locations.  相似文献   

17.
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, 240Pu, 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.  相似文献   

18.
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.  相似文献   

19.
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.  相似文献   

20.
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