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101.
采集并分析全场不同母质形成的有代表性的土壤样本142个.研究结果表明,各类土壤全B、Mo、Zn和Mn含量的平均值均低于全国平均值,全量Cu平均值高于全国平均值.有效B、Mo、Zn和Mn含量的平均值均低于临界值,有效Cu的平均值稍高于临界值;但66.7%的土样有效Cu含量低于临界值.硼、钼、锌和锰严重缺乏,铜多数缺乏.全场各类土壤的微量元素含量差异较大,各类土壤微量元素的垂直和水平分布特征不尽相同,尤其是垂直分布差异明显.从土壤微量元素的全量与母质的关系来看,以玄武岩、紫色砂页岩母质形成的土壤全量较高,砂砾岩母质形成的土壤全量中等,砂页岩和冲积物母质形成的土壤全量较低. 相似文献
102.
廖金凤 《生态与农村环境学报》1998,(4)
海南省位于我国热带地区,草本植物微量元素组成可反映热带区域生物地球化学特点。海南植物微量元素含量属正常范围值,仅个别植物Cd、Hg含量偏高。植物Zn、Cu、Mo含量大多在5mg/kg以上,Pb、Cu、Cd含量一般低于2mg/kg,Hg、As、Ni通常不足1mg/kg。雀稗(Paspalumcommersoni)、地胆草(Elephantopusscaber)等微量元素含量普遍较高。红裂稃草(Schizachyriumsanguineum)、白茅(Imperatacylindrica)等微量元素含量一般较低。植物微量元素组成与植物种类及其生境条件有关。生物吸收系数反映植物摄取元素的强度,Mo、Cd、Hg、Zn、Cu的生物吸收系数通常大于1.0,属强积聚元素,Pb、Cr、Ni、As的生物吸收系数大多低于0.3,是弱摄取元素。 相似文献
103.
A mixed-integer programming model that minimizes the social abatement cost is used to investigate whether a market equilibrium
condition could be reached in a newly proposed permit-trading market for nitrogen oxide control in Taiwan. Unlike in previous
studies, unit pollution abatement cost is determined endogenously by incorporating technology adoption as a binary decision
variable. The results show that when technologies are lumpy and irreversible, disequilibrium might occur due to firms’ inability
to manage their emission levels after installing equipment with fixed size and control capacity.
相似文献
Chao-ning LiaoEmail: |
104.
In vitro activity of antimicrobial agents against Legionella isolated from environmental water systems: first results from Turkey 总被引:1,自引:0,他引:1
Haluk Erdogan Fusun Can Muge Demirbilek Funda Timurkaynak Hande Arslan 《Environmental monitoring and assessment》2010,171(1-4):487-491
We evaluated the in vitro activity of antimicrobial agents against Legionella obtained from hotel and hospital water systems in three different regions of Turkey. Sixty-five Legionella strains (Legionella pneumophila serogroup 6 [n?=?32], L. pneumophila serogroup 1 [n?=?27], L. pneumophila serogroup 3 [n?=?2], and Legionella spp. [n?=?4]) were tested against levofloxacin, ciprofloxacin, clarithromycin, azithromycin, and rifampicin. The minimum inhibitory concentration (MIC) values of each antimicrobial agent for these strains was determined by the microdilution method using buffered yeast extract medium supplemented with 0.1% ketoglutarate broth. L. pneumophila ATCC 33152, Staphylococcus aureus ATCC 29213, and Escherichia coli ATCC 25922 were used as controls. Minimum inhibitory concentration values were in the following ranges: clarithromycin 0.001–0.5 mg/L, azithromycin 0.001–0.5 mg/L, levofloxacin 0.001–0.5 mg/L, ciprofloxacin 0.001–0.125 mg/L, and rifampicin 0.001– 0.5 mg/L. The MIC90 for rifampicin, levofloxacin, ciprofloxacin, azithromycin, and clarithromycin were 0.015, 0.125, 0.06, 0.125, and 0.06 mg/L, respectively. To the best of our knowledge, this is the first study to determine in vitro activities of antimicrobial agents against Legionella species in Turkey. Rifampicin had the lowest MIC90 value. It would seem that azithromycin and clarithromycin exhibit good activity as well as levofloxacin and ciprofloxacin against Legionella isolated from environmental water systems in Turkey. 相似文献
105.
106.
Oguz Can Turgay Esin Eraydın Erdogan Ayten Karaca 《Environmental monitoring and assessment》2010,170(1-4):45-58
In order to investigate the bioremedial potential of humic deposit (leonardite), the effects of the treatments of leonardite and a commercial bioaugmentation agent on the degradation of a variety of petroleum hydrocarbons (C13–C31) and soil enzyme activities (urease acid-alkaline phosphatase and dehydrogenase) were tested within a soil incubation experiment lasting 120 days. Experimentally crude-oil-contaminated soil (2.5%) was regulated to a C:N:P ratio (100:15:1; Oilcon), amended with 5% of leonardite and regulated to the same C:N:P ratio (Oilcon-L) or mixed with a commercial bioaugmentation product (Oilcon-B), respectively. In the short period of incubation (60 days), Oilcon and Oilcon-B treatments showed higher hydrocarbon degradations, whereas Oilcon-L showed higher hydrocarbon degradation over Oilcon and Oilcon-B treatments in the long-term (120 days). Applying contaminated soil with leonardite increased urease (LSD, 4.978, *P?<?0.05) and dehydrogenase (LSD, 0.660, *P?<?0.05) activities. However, acid and alkaline phosphatase activities showed no certain inclination between different treatments. Dehydrogenase seemed to be more related to hydrocarbon degradation process. Overall results showed that leonardite enhanced biodegradation of petroleum hydrocarbons and also stimulated soil ecological quality measured as soil enzyme activities. 相似文献
107.
The removal of the organic toxic chemicals di-n-butyl phthalate (DBP), di-2-ethyl hexyl phthalate (DEHP), nonylphenol (NP), and bisphenol-A (BPA) by laccase obtained from the spent mushroom compost (SMC) of the white rot fungi, Ganoderma lucidum, was investigated. The optimal conditions for the extraction of laccase from SMC required using sodium acetate buffer (pH 5.0, solid : solution ratio 1 : 5), and extraction over 3 h at 4 °C. The removal of NP was enhanced by adding CuSO(4) (1 mM), MnSO(4) (0.5 mM), tartaric acid (20 mM), 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS; 1 mM), and 1-hydroxybenzotriazole (HBT; 20 mg L(-1)), with ABTS yielding a higher NP removal efficiency than the other additives. At a concentration of 2 mg L(-1), DBP, DEHP, NP, and BPA were almost entirely removed by laccase after incubation for 1 day. The removal efficiencies, in descending order of magnitude, were DBP > BPA > NP > DEHP. We believe that these findings could provide useful information for improving the efficiency of the removal of organic toxic chemicals in the environment. 相似文献
108.
2009—2010年冬季和夏季在重庆市某代表性城区对大气中苯系物进行观测,并应用苯与甲苯特征比值(B/T)和因子分析法对苯系物来源进行了分析。结果表明,2种源分析方法具有较好的一致性,涂料及溶剂的生产与使用以及机动车尾气和油品使用是该研究区域苯系物的主要来源,贡献率分别为59.3%和16.2%。不同功能区、不同季节,苯系物来源构成有所差异。除受汽车尾气影响外,夏季受涂料、溶剂等生产使用的影响也较大,尤其是投诉集中点位、混合区和工业区;冬季,投诉集中点位主要受涂料、溶剂等生产使用等影响,其他点位可能还受到燃烧源的影响。 相似文献
109.
学龄儿童肺功能水平影响因素的研究 总被引:1,自引:0,他引:1
用逐步回归分析方法对与室内、外空气污染和机体状况等有关的因素对广州市学龄儿童肺功能 (FVC、FEV1 、PEFR和 FEF2 5~ 75 )水平的影响进行研究。结果提示 ,影响肺功能水平的主要因素是内因 ,身高的影响最明显 ,呼吸系统疾病或症状发生与肺功能水平下降有关 ;室外空气污染使肺功能水平下降 ,SO2 、NOx 和 PM2 .5 的影响明显 ,PM2 .5 的影响明显大于 PM1 0 和 TSP;居室或厨房通风不良、家庭烹饪用不洁燃料对儿童肺功能的生长不利 ;被动吸烟对女性儿童肺功能有不利影响。对各种影响因素 ,PEFR和 FEF2 5~ 75 比 FVC和 FEV1 更为敏感 相似文献
110.
This article reports on soil samples collected from Hsiang-Shan wetland, Taiwan. Canonical discriminant analysis (CDA) was applied to identify an existing habitat type's scheme by identifying the physico-chemical properties of sediment in Hsiang-Shan wetland. The three constructed discriminant functions (CDFs) showed a marked contribution by most of the discriminant variables, and the recognition capacities in these three CDFs were 49.5, 32.8 and 17.7%. Our study revealed that the most important latent factors in Hsiang-Shan wetland are soil texture-caused factor, ocean current-caused factor, nutrient-caused factor, and the redox reaction-caused factor. And the most sensitivity parameters in this habitat followed the descending order: OBD, EC, Eh, sand, TN, porosity, STP, silt, VCP and pH. And the inhabited sediment properties for U. formosensis in terms of soil texture are sand, silt, and clay (34.05, 29.72, and 32.35%, respectively): that is clay loam soil. We also found that U. formosensis preferred to inhabit the upper intertidal zone, spending 8.41% of the time submerged. Vegetation coverage on the ground was less than 2.20%, showing that it preferred to live in a bare intertidal habitat. Concerning nest choosing, excavating burrows is more difficult when a high soil penetration force is required, and in this study the soil penetration force for 20 cm was found to be is 45.98 N/cm(2). The results will be helpful in developing a methodology for use by the government in refining its management programs. 相似文献