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1.
我国沙尘暴灾害及其治理对策初步研究   总被引:4,自引:0,他引:4  
分析研究了沙尘暴的成因、时空分布、发展趋势及造成的灾害,结合国外经验提出了我国治理的对策建议。  相似文献   

2.
A simple and accurate method of determining metalaxyl and cymoxanil in pepper and soil was developed by ultra-performance liquid chromatography–photodiode array detection. The limits of detection were 0.015 mg/kg for metalaxyl and 0.003 mg/kg for cymoxanil. The limits of quantification were 0.05 mg/kg for metalaxyl in pepper and soil as well as 0.01 mg/kg for cymoxanil in pepper and soil. Recoveries of pepper and soil were investigated at three spiking levels and ranged within 77.52 to 102.05 % for metalaxyl and 87.15 to 103.21 % for cymoxanil, with relative standard deviations below 9.30 %. For field experiments, the half-lives of metalaxyl were 3.2 to 3.9 days in pepper and 4.4 to 9.5 days in soil at the three experimental locations in China. At harvest, pepper samples were found to contain metalaxyl and cymoxanil well below the maximum residue limit MRLs of the European Union (EU) following the recommended dosage and the interval of 21 days after last application.  相似文献   

3.
A simple and accurate method for the determination of bismerthiazol and its metabolite 2-amino-5-mercapto-1,3,4-thiadiazole was developed in Chinese cabbage and soil by high-performance liquid chromatography-diode array detection in this study. The limits of detection were 0.06 mg/kg for bismerthiazol and 0.03 mg/kg for 2-amino-5-mercapto-1,3,4-thiadiazole, respectively. Recoveries of cabbage and soil were investigated at three spiking levels and were in the range of 84.0–96.0 % for bismerthiazol and 71.0–74.6 % for 2-amino-5-mercapto-1,3,4-thiadiazole, with relative standard deviations below 7.0 %. For field experiments, the half-life of bismerthiazol was 2.4–2.5 days in Chinese cabbage and 2.5–4.8 days in soil at the two experimental locations in China. Dissipation residues of 2-amino-5-mercapto-1,3,4-thiadiazole were lower than 0.72 mg/kg. Terminal residues of bismerthiazol and its metabolite were less than 3.0 and 0.3 mg/kg in Chinese cabbage, respectively. No bismerthiazol or metabolite residues were detected in soil on days 5, 7, 10, and 14 after the last spraying at the two dosage levels.  相似文献   

4.
李江 《干旱环境监测》2006,20(4):246-248
针对目前室内环境监测工作出现的种种问题,就如何规范的开展室内环境监测工作,更好地为社会提供真实、准确、有效的监测数据,本文提出相关的探讨。  相似文献   

5.
A simple residue analytical method using the quick, easy, cheap, effective, rugged, and safe (QuEChERS) procedure for the determination of trifloxystrobin and its metabolite trifloxystrobin acid (CGA321113) in tomato and soil was developed using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The limits of detection were 0.0005 mg/kg for trifloxystrobin and 0.001 mg/kg for trifloxystrobin acid, respectively. The average recoveries in tomato and soil ranged from 73–99 % for trifloxystrobin and 75–109 % for trifloxystrobin acid, with relative standard deviations below 15 %. The method was then used to study the dissipation and residues in tomato and soil. The dissipation half-lives of trifloxystrobin in tomato were 2.9 days (Beijing) and 5.4 days (Shandong), while in soil were 1.9 days (Beijing) and 3.0 days (Shandong), respectively. The final results showed that the major residue compound was trifloxystrobin in tomato whereas it was its metabolite, trifloxystrobin acid, in soil. The final residues of total trifloxystrobin (including trifloxystrobin acid) were below the EU maximum residue limit of 0.5 mg kg?1 in tomato 3 days after the treatment.  相似文献   

6.
7.
针对太原市空气臭氧污染较为严重的问题,开展臭氧主要前体物醛酮化合物质量浓度及其变化规律研究.利用2,4-二硝基苯肼固相吸附/高效液相色谱方法,通过对太原市2019年冬季和夏季大气的醛酮化合物进行分析,发现太原市冬季总醛酮化合物的平均质量浓度为13μg/m3,低于夏季的27μg/m3.其中甲醛、乙醛和丙酮质量浓度最高,且...  相似文献   

8.
A long-term study of the effect of artificial aeration (destratification) of a water storage dam upon the speciation of iron and manganese in the dam waters has been undertaken. Separation of dam samples into soluble and insoluble forms by selective membrane filtration was undertaken before using the techniques of EPR spectroscopy, ion chromatography and gel filtration to assess the speciation of soluble species, and selective extraction and surface analysis (ESCA, SIMS and SEM) techniques to determine the speciation of particulate iron and manganese species. The percentages of soluble iron and manganese before (1983–85) and after (1986–88) artificial aeration are compared for the periods Jan–Dec, Jan–Mar, and Jun–Aug at three depths 6 m, 15 m and 0.5 m above the dam base, to assess the importance of seasonal changes in the various depths of the dam. Although aeration had an initial marked reduction in levels of soluble iron and manganese at all depths of the dam, the concentrations of these mtals showed a steady increase over succeeding years. Analysis of the figures over summer and winter periods shows that the reduction of soluble iron was maintained in summer, but not during winter. Upon aeration, the initial reduction of soluble manganese concentration was maintained in succeeding years in the epilimnic regions of the dam, but not in the hypolimnion. Statistical analysis of data has been undertaken to correlate the changes in relationship between the various forms of iron and manganese with the advent of aeration.  相似文献   

9.
The social and economic implications of atmospheric change on biodiversity need to be seen in a global context of major shifts in the conceptualization and management of our relationship with nature. Traditionally, we have conceptualized the atmosphere and the other creatures of the biosphere as separate from the human, but their quasi-autonomy is now becoming subject to more and more human management. This raises not only economic issues, but social, political, and ethical concerns that will have substantial influence on public policy. Among these are the commodification of genetic material; the privatization of traditional knowledge; and the management of information. In this broader context, the paper examines an array of current and proposed strategies of response to changes in biodiversity as a result of climatic and other stresses.  相似文献   

10.
Canada responded to the Global Biodiversity Convention by completing the Canadian Biodiversity Strategy in 1995. At the same time, Environment Canada also completed a national Science Assessment on Biodiversity. During this period, the Smithsonian Institution, in partnership with Parks and Environment Canada, initiated the implementation of a global biodiversity monitoring program in Canada. Under the auspices of the United Nations Man and the Biosphere Program, the SI/MAB monitoring protocols and plots have spread across Canada at an unprecedented rate. National champions in the science and educational sectors, working within an inter-disciplinary ecological framework, have guided the development, education, quality control and sharing of atmosphere-biodiversity observations electronically.Atmospheric-Biodiversity Networks and Networking have traditionally operated within separate mandates with little degree of integration. Air-Bio Networks were designed within an integrated framework to better understand the atmospheric stress on biodiversity and the adaptation actions, nationally and regionally. Detailed examples of the cumulative effects of climate change, stratospheric ozone depletion, acid deposition, ground-level ozone, suspended particulate matter and hazardous air pollutants on biodiversity will be discussed using a Southern Ontario case study. In addition, recommendations will be presented for future paired SI/MAB plots, linked networks and networking for adaptation within the context of climate, chemical and ecological gradients.  相似文献   

11.
Perchlorate is known to competitively interfere with iodide uptake by the thyroid gland and thereby human exposure to perchlorate is a public health concern. Prevalence of perchlorate in dairy milk is documented; nevertheless, co-occurrence of perchlorate with other thyroid-binding monovalent ions such as iodide and nitrate is not well understood. In this study, we analyzed perchlorate, iodide, and nitrate-N in dairy milk, water and other dairy-related samples collected from Japan and Sri Lanka. Concentrations of perchlorate in Japanese dairy milk samples ranged from 1.03 to 14.1 ng ml(-1); the corresponding concentrations in dairy milk and powdered milk from Sri Lanka were 1.14-38.5 ng ml(-1). Perchlorate concentrations in commercial milk were significantly higher in Japan than in Sri Lanka, while iodide and nitrate levels in milk between the two countries were comparable. All three ions were ubiquitously found in water samples from Japan and Sri Lanka. Analysis of colostrum and raw milk collected from cows fed with the same feed for over 30 days showed no significant temporal variations in perchlorate, iodide and nitrate-N concentrations. A significant positive correlation was found between the concentrations of perchlorate and iodide in Japanese commercial milk. The concentrations of perchlorate and nitrate-N in water samples analyzed from both countries also showed a significant positive correlation. The exposure estimation revealed that dairy milk provides a greater source for perchlorate and iodide, while water predominantly contributes nitrate-N intake for all age groups in both counties. Infants and children demonstrated the highest estimated perchlorate, iodide and nitrate-N intake on a body weight basis in comparison to other age groups. Therefore, further studies of risk associated with perchlorate may need to reconsider co-existence of iodine and other iodide transport inhibitors in food.  相似文献   

12.
The introduction of earthworms into soils contaminated with metals and metalloids has been suggested to aid restoration practices. Eisenia veneta (epigeic), Lumbricus terrestris (anecic) and Allolobophora chlorotica (endogeic) earthworms were cultivated in columns containing 900 g soil with 1130, 345, 113 and 131 mg kg(-1) of As, Cu, Pb and Zn, respectively, for up to 112 days, in parallel with earthworm-free columns. Leachate was produced by pouring water on the soil surface to saturate the soil and generate downflow. Ryegrass was grown on the top of columns to assess metal uptake into biota. Different ecological groups affected metals in the same way by increasing concentrations and free ion activities in leachate, but anecic L. terrestris had the greatest effect by increasing leachate concentrations of As by 267%, Cu by 393%, Pb by 190%, and Zn by 429% compared to earthworm-free columns. Ryegrass grown in earthworm-bearing soil accumulated more metal and the soil microbial community exhibited greater stress. Results are consistent with earthworm enhanced degradation of organic matter leading to release of organically bound elements. The degradation of organic matter also releases organic acids which decrease the soil pH. The earthworms do not appear to carry out a unique process, but increase the rate of a process that is already occurring. The impact of earthworms on metal mobility and availability should therefore be considered when inoculating earthworms into contaminated soils as new pathways to receptors may be created or the flow of metals and metalloids to receptors may be elevated.  相似文献   

13.
根据国内危险化学品分类与分级管理现状,结合北京大学实验室危险化学品管理工作实际情况,总结了危险化学品源头管控、过程管理、监督检查等方面的分级分类管理策略与方法,介绍了北京大学在实验室安全教育与培训、技防与物防建设、信息化技术运用、奖惩机制建设方面的经验,以期为提升危险化学品管理水平、消除安全隐患、提高高校实验室安全管理质量提供参考。  相似文献   

14.
废旧干电池的环境污染防治及回收利用   总被引:5,自引:0,他引:5  
王颖 《干旱环境监测》2002,16(2):113-115
介绍了各种干电池的基本化学组成,分析了废旧干电池污染环境的主要途径及对人类的危害,并就回收利用问题提出建议。  相似文献   

15.
Organic contaminants [polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), polybrominated diphenylethers (PBDEs), nonylphenols], organotin compounds and trace metals (cadmium, chromium, mercury and zinc) were determined in flounder (Platichthys flesus) liver and sediment from the Amsterdam harbour (North Sea Canal) and Rotterdam harbour (Euromonding) and off the Dutch coast between the Amsterdam and Rotterdam harbour mouths in order to assess the level of contamination in these harbours and to study contamination gradients.  相似文献   

16.
阐述了环境监理与环境管理的关系,指出了以制度和程序规范两者的分工与合作可充分发挥环境监理在环境管理中的作用  相似文献   

17.
The aim of this study was to compare the personal exposure to particles and bioaerosols with that measured by stationary samplers in the main microenvironments, i.e., the home and the workplace. A random sample of 81 elementary school teachers was selected from the 823 teachers working for two councils in eastern Finland for the winter time measurement period. Bioaerosol and other particles were collected on filters by button samplers using personal sampling and microenvironmental measurements in homes and workplaces. The 24-hour sampling period was repeated twice for each teacher. Particle mass, absorption coefficient of the filter and the concentration of viable and total microorganisms were analyzed from each filter. In this paper, the study design, quality assurance principles and results of particle and bioaerosol exposure are described. The results show that particle mass concentrations, absorption coefficient and fungi were higher in personal exposure samples than in home and workplace samples. Furthermore, these concentrations were usually lower in the home than in the workplace. Bacterial concentrations were highest in heavily populated workplaces, while the viable fungi concentrations were lowest in workplaces. The fungi and bacteria results showed high variation, which emphasises the importance of quality assurance (duplicates and field blanks) in the microbial field measurements. Our results indicate that personal exposure measurements of bioaerosols in indoor environments are feasible and supplement the information obtained by stationary samplers.  相似文献   

18.
畜禽养殖场污染状况监测与评价   总被引:1,自引:0,他引:1  
对河南省三个有代表性的规模化养殖场污染物排放及其对周围环境的影响进行了调查、监测及评价,结果表明,畜禽养殖污染已成为农业面源污染的重要来源,对其周围地表水和地下水产生较大影响。  相似文献   

19.
The dissipation and residues of bispyribac-sodium in rice cropping system were studied. Bispyribac-sodium residues were extracted by a simple analytical method based on QuEChERs and detected by LC-MS/MS. The limit of detection for bispyribac-sodium of this method was 0.375?×?10?3 ng. The limit of quantification (LOQ) was 5.0 μg/kg for rice plant samples, 2.0 μg/kg for rice hull, 0.2 μg/kg for water, and 0.1 μg/kg for soil and husked rice samples. The average recoveries of bispyribac-sodium ranged from 74.7 to 108 %, with relative standard deviations less than 13 %. The half-lives of bispyribac-sodium in rice plant, water, and soil were in the range of 1.4–5.6 days. More than 90 % of bispyribac-sodium residue dissipated within 5 days. The final residues of bispyribac-sodium in rice were all below LOQ at harvest time.  相似文献   

20.
Organochlorines and selenium in California night-heron and egret eggs   总被引:2,自引:0,他引:2  
Exceptionally high concentrations of DDE were found in black-crowned night-heron (Nycticorax nycticorax) (geometric mean 8.62 g g–1 wet wt.) and great egret (Casmerodius albus) (24.0 g g–1) eggs collected from the Imperial Valley (Salton Sea), California in 1985. DDE concentrations in 14 of the 87 (16%) randomly selected night-heron eggs from six colonies (two in San Francisco Bay, three in the San Joaquin Valley, and one at Salton Sea) were higher than those associated with reduced reproductive success of night-herons (8 g g–1). In addition, mean shell thickness of night-heron eggs collected from the San Joaquin Valley and from San Francisco Bay during 1982–1984 was significantly less than pre-DDT thickness and was negatively correlated (r=–0.50, n=75, P<0.0001) with DDE concentration. Mean selenium concentration in night-heron eggs from Salton Sea (1.10 g g–1) was significantly higher than in eggs from three locations in the San Joaquin Valley, and in egret eggs from Salton Sea.  相似文献   

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