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121.
The contamination of soils by toxic and/or hazardous organic pollutants, especially with crude oil, is a widespread problem. This study was conducted in a petroleum-contaminated area in a Tehran oil refinery to find petroleum-resistant plants and their rhizospheral fungal strains with bioremediation potency. The plants growing in the oil-polluted area were collected and determined taxonomically. Root samples of the plant species were collected from a polluted area and fungal strains determined by laboratory methods and taxonomical keys. The growth ability of the isolated fungal strains was studied in media containing 1%–15% crude oil. Results showed that seven plant species were of the highest density in the contaminated area: Alhagi persarum, Hordeum marinum, Peganum harmala, Phragmites australis, Prosopis farcta, Salsola kali, and Senecio glaucus. The root-associated fungi were isolated and showed that the fungal variation in the oil-polluted area is higher than that in a non-polluted area. The growth assay of isolated fungal strains showed that all studied fungal strains were able to form colonies at the applied concentrations but Alternaria sp. and Rhizopus sp. were the most resistant ones. Some plants were resistant to oil pollution, which also had positive effects on the fungal strains.  相似文献   
122.
Monitoring and modeling of the concentrations of trihalomethanes (THMs) within four water treatment plants (WTPs) and distribution lines in Fayoum City, Egypt, were studied. Sampling sites for raw and treated waters were determined by global positioning system and the Arc geographic information system software was used for mapping. THMs were monitored using 25 sampling points located at the plant exit and through the distribution lines up to the plant extremity. Results indicated that the THMs concentration varied significantly but it was very rarely higher than the allowed maximum contaminant level of 100 μg L?1. However, at the dead zones in the distribution lines, the THMs increased by about 160% compared to in-plant level. Furthermore, the level of THMs in hot months was about 1.3 times higher than in cold ones. The influence of some independent variables such as temperature, pH, ammonia concentration, total organic carbon and color were investigated by Pearson model to find their correlation with the rate of THMs formation in WTPs. The resulted R values ranged from 0.81 to 0.98. Successful application of the model to a selected region on the distribution lines has resulted in a correlation coefficient of 0.98.  相似文献   
123.
The Sonbhadra district in the Singrauli area of Uttar Pradesh, India, has many coal mines and thermal power plants and is a critically polluted area. Many residents of this area reported adverse health conditions which may be linked to metal pollution, especially of mercury investigated here.

In May 2012, samples of water (23), soil (7), blood, hair, and nails from persons showing adverse health conditions selected at random were collected and analyzed for total mercury by atomic absorption spectrometry.

Twenty percent drinking water samples contained mercury from 3 to 26 μg L?1 (3–26 times the permissible limit). Soil samples had 0.5–10.1 mg kg?1 Hg.

The average concentrations of mercury in human blood, hair, and nails were found to be 34 μg L?1, 7.4 mg kg?1, and 0.8 mg kg?1, respectively. Mercury concentrations in the blood of these persons were 45 and 28 μg L?1 on average in the case of men and women. This is much higher than the safe level of 5.8 μg L?1 set by the United States Environmental Protection Agency (USEPA).

It was concluded that all residents of Sonbhadra sampled could be suffering from mercury toxicity as the area is polluted by Hg released from the coal-fired thermal power plants.  相似文献   
124.
参照测量不确定度评定与表示的国家技术规范,基于近年来我国燃煤电厂常规污控设备协同脱汞的现场测试数据(文献报道和实测值)及各省原煤w(汞)的实测值,初步构建了国内燃煤电厂烟气汞排放不确定度的计算方法,并以2010年的燃煤量、污控方式布局为基础,计算了该年度汞排放的不确定度. 结果表明:2010年我国燃煤电厂烟气汞排放的总不确定度为48.8t,占平均排放总量的34.3%;其中60.2%源于污控设备脱汞效率的不确定度,39.8%源于原煤w(汞)的不确定度;采用ESP(静电除尘)、ESP+WFGD(静电除尘+湿法脱硫)、SCR+ESP+WFGD(选择性催化还原脱硝+静电除尘+湿法脱硫)和FF(袋式除尘)大气污控组合的机组各存在6.0、32.2、9.7和0.9t的烟气汞排放不确定度,分别占各对应机组烟气汞排放量的19.3%、32.8%、84.6%和53.6%,其中SCR+ESP+WFGD污控组合烟气汞排放的相对不确定度最大. 随着我国烟气脱硝工作全面推行,2015年以后,SCR+ESP+WFGD污控措施(组合)的机组所占比例将会提高到66%以上,如果仍以现有数据为基础,则来自SCR+ESP+WFGD污控措施(组合)机组的烟气汞排放不确定度将会大幅增加,因此急需增加对该类装置脱汞效率的实测样本数量.   相似文献   
125.

While the potential of indigenous knowledge for health care is fully recognised in the literature and by many health professionals, the practices of so many indigenous peoples go unrecorded and untested. Indigenous knowledge remains essentially untapped, an unwritten resource involving information, language and skills in many groups, languages, cultures and environments. An attempt is made in this paper to identify selected indigenous health technologies in a tribal area of Bihar State, India; to describe the treatments, their application and preparation; and to link the traditional practice with the relevant scientific information to test or determine the validity of the practices. These practices were found to be effective in the treatment of a variety of health problems, and most were also scientifically confirmed. The paper argues, however, that other plant uses practised by tribal people still need to be explored: in order to popularise more widely the authenticated practices; to preserve indigenous knowledge; to integrate or blend it with scientific knowledge so that health professionals and healthcare users may benefit from a wider range of healthcare strategies which are environmentally unthreatening.  相似文献   
126.
采用原位移地技术,研究了不同区域气候条件影响下,纳帕海4种常见湿地植物的株高、茎粗、生物量等生长特性,以及叶绿素a、叶绿素b、总叶绿素含量、叶绿素a/b值、光化学量子效率(Fv/Fm)、电子传递速率(ETR)、实际光化学量子效率(Phips2)、光化学猝灭系数(qP)、非光化学猝灭系数(NPQ)等生理生化指标,分析探讨了湿地植物对不同区域气候条件的响应差异和适应策略。研究发现气候条件的改变对湿地植物的生长、叶绿素含量及荧光参数产生重要影响。随着温度的上升,水葱Scirpus tabernaemontani和茭草两种广布种Zizania caduciflora均表现出良好的适应性,生物量、叶绿素含量、Fv/Fm、ETR、Phips2、qP值不同程度升高,生长状况良好。刘氏荸荠Heleocharis liouana也表现出较好的适应性,当气温上升到一定程度后,虽然Fv/Fm、ETR、Phips2、qP值降低,但其通过调节叶绿素含量、热耗散来减轻伤害,气候变化对其生长的影响较小。而北温带分布型的黑三棱Rhizoma scirpi yagarae对气候变化的适应性较差,当温度上升到一定程度后, Fv/Fm、ETR、Phips2、qP、NPQ都出现大幅下降,生长停滞,生物量下降,对温度上升极为敏感。可以推测,随着全球变暖,像黑三棱这样的物种,其生存将面临极大的威胁,而高原湿地生态功也将能受到损害。  相似文献   
127.
Abstract: Airborne lidar is a remote‐sensing tool of increasing importance in ecological and conservation research due to its ability to characterize three‐dimensional vegetation structure. If different aspects of plant species diversity and composition can be related to vegetation structure, landscape‐level assessments of plant communities may be possible. We examined this possibility for Mediterranean oak forests in southern Portugal, which are rich in biological diversity but also threatened. We compared data from a discrete, first‐and‐last return lidar data set collected for 31 plots of cork oak (Quercus suber) and Algerian oak (Quercus canariensis) forest with field data to test whether lidar can be used to predict the vertical structure of vegetation, diversity of plant species, and community type. Lidar‐ and field‐measured structural data were significantly correlated (up to r= 0.85). Diversity of forest species was significantly associated with lidar‐measured vegetation height (R2= 0.50, p < 0.001). Clustering and ordination of the species data pointed to the presence of 2 main forest classes that could be discriminated with an accuracy of 89% on the basis of lidar data. Lidar can be applied widely for mapping of habitat and assessments of habitat condition (e.g., in support of the European Species and Habitats Directive [92/43/EEC]). However, particular attention needs to be paid to issues of survey design: density of lidar points and geospatial accuracy of ground‐truthing and its timing relative to acquisition of lidar data.  相似文献   
128.
采用人工模拟熏气法,研究了36种广州市园林绿化植物对SO2和NO2气体吸收净化能力,以系统聚类分析方法为依据,将参试植物的吸收净化能力划分为强性、较强、中等、较弱及弱5个等级。结果显示,在不同SO2质量浓度(0.259和0.448 mg.m-3)环境下,黄槐、鸡冠刺桐、红花银桦、木棉、红千层、大花紫薇、复羽叶栾树吸收SO2能力具有强或较强的能力,而罗汉松、竹柏、深山含笑、乐昌含笑、观光木、樟树、阴香、双翼豆、印度紫檀、大花五桠果、长芒杜英、五月茶、海南蒲桃、芒果、海南红豆、糖胶树和幌伞枫吸收SO2能力表现为较弱或弱;在NO2质量浓度(0.149和0.428 mg.m-3)环境下,黄槐、黄葛榕、红花银桦、红千层、麻楝、复羽叶栾树、大花紫薇和小叶榄仁吸收净化NO2能力为较强或强,而深山含笑、五月茶、芒果、海南红豆、糖胶树和桂花叶片对NO2吸收能力表现为较弱或弱。在不同SO2和NO2浓度环境下,黄槐、红花银桦、红千层、复羽叶栾树和大花紫薇叶片对SO2和NO2吸收净化能力表现为强或较强,而深山含笑、五月茶、芒果、海南红豆、糖胶树叶片对SO2和NO2吸收净化能力为较弱或弱。研究结果为珠三角城市功能型园林植物选择和广东生态景观林带建设提供科学依据。  相似文献   
129.
植物区系地理分布格局的研究有助于更好地理解植物区系的起源、迁移和分化。研究利用覆盖云南地区全境的植物区系分布信息,探讨了云南地区植物区系属的多度及区系过渡性的地理分布格局。结果表明,所有热带区系属的多度均随着纬度升高呈递减趋势;大多数温带区系属的多度随着纬度的升高呈递增趋势。中亚分布(T13)属的多度的高值主要出现在滇西北地区,尤其是在金沙江、澜沧江和怒江的上游地区,但在其它地区十分少见。地中海、西亚至中亚分布(T12)属的多度的高值也出现在滇西北地区,但在其它地区无明显空间分布规律;中国特有分布(T15)属在滇西北地区最为丰富,其次是滇东南地区,大致以“田中线”为界,界线以西地区的中国植物特有属的多度明显低于界线以东地区。从南到北,植物区系过渡性基本上呈单调递增格局,这一格局的形成可能与区系成分的迁移和地形格局有关。大理州以南的低海拔地区,热带区系成分占据主导地位,并占据了云南大部分的土地面积,这在一定程度上证实了云南地区总体上是一个“热带山原”的假说。本研究与其它研究的不同可能源于与源数据和取样尺度的差异。  相似文献   
130.
人工湿地污水处理系统中植物体系的构建与展望   总被引:2,自引:0,他引:2  
植物是人工湿地系统中的重要组成成分之一,它不仅可以起到净化污水的作用,而且还为微生物提供生存环境,同时具有景观价值。因此要选择适应性强、生物量大、根系发达、具有抗逆性的植物作为湿地植物。由于陆生植物受季节影响小且易于管理,超富集植物和转基因植物具有较高的吸收、吸附和富集的作用的特点相继成为湿地系统中植物研究的热点。而且通过合理配置植物系统可以提高湿地系统净化效果。湿地植物仍存在受季节变化的影响,植物的衰退,植物收割的后续处理等问题,仍有待研究。随着对湿地植物研究的深入,人工湿地系统一定会获得更加广阔的应用前景。  相似文献   
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