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1.
Five years after the 1997 Nakhodka oil spill in the Sea of Japan, seven bacterial strains capable of utilizing the heavy oil spilled from the Nakhodka Russian oil tanker were isolated from three coastal areas (namely Katano Seashore of Fukui Prefecture, Osawa and Atake seashores of Ishikawa Prefecture) and the Nakhodka Russian oil tanker after a 5-year bioremediation process. All bacterial strains isolated could utilize long-chain-length alkanes efficiently, but not aromatic, and all of them were able to grow well on heavy oil. Using 16S rDNA sequencing, most of the strains were affiliated to Pseudomonas aeruginosa. Comparing between the year 1997 (at the beginning of bioremediation process) and the year 2001 (after 5 years of bioremediation), there was no significant change in morphology and size of hydrocarbon-degrading bacteria during the 5-year bioremediation. Scanning and transmission electron microscopic observations revealed that a large number of hydrocarbon-degrading bacteria still existed in the sites consisting of a variety of morphological forms of bacteria, such as coccus (Streptococcus and Staphylococcus) and bacillus (Streptobacillus). On the application of bioremediation processes on the laboratory-scale, laboratory microcosm experiments (containing seawater, beach sand, and heavy oil) under aerobic condition by two different treatments (i.e., placed the inside building and the outside building) were established for bioremediation of heavy oil to investigate the significance of the role of hydrocarbon-degrading bacteria on them. There was no significant bacterial activity differentiation in the two treatments, and removal of heavy oil by hydrocarbon-degrading bacteria in the outside building was slightly greater than that in the inside building. The values of pH, Eh, EC, and dissolved oxygen (DO) in two treatments indicated that the bioremediation process took place under aerobic conditions (DO: 1-6 mg/l; Eh: 12-300 mV) and neutral-alkaline conditions (pH 6.4-8) with NaCl concentrations of 3-15% (ECs of 45-200 mS/cm).  相似文献   

2.
3.
In November 2002, the Prestige oil tanker was wrecked in front of Galician coast (NW of Spain), spilling near 63,000 tons of heavy oil until February 2003. Contamination produced was very extensive (70% of Galician beaches were reached by the oil) but heterogeneous, alternating intensely affected zones with neighbour locations where the repercussion was minimal. The objective of this study was to monitor sea environment contamination caused by Prestige oil spill during an 11-month period (August 2003-June 2004, nine samplings) in two locations of Galician coast with different geographical properties (Lira and Ancoradoiro beaches), by means of chemical determination of total polycyclic aromatic hydrocarbons (TPAH) in seawater, and using as exposure biomarker TPAH content in mussel (Mytilus galloprovincialis) tissues, and as effect biomarker DNA damage in mussel gills, evaluated by the comet assay. In addition, recovery ability of the mussels was determined after a 7-day stay in the laboratory. TPAH contents in seawater were very high in the earliest samplings, but then they maintained below 200 ng L(-)(1), similar to reference seawater. However, TPAH levels in mussel tissues were more variable: they increased again from January 2004, probably due to the adverse meteorological conditions that turned over the sea bottom and dispersed the oil accumulated in sediments. In most samplings, these levels decreased during the recovery stage. DNA damage in oil-exposed mussels was significantly higher than in reference mussels, both before and after the recovery phase, but they did not differ to one another. Comet tail length was slightly reduced during the recovery stage, indicative of a certain DNA repair in exposed mussels. This study showed up the importance of monitoring sea contamination events during an extended time, not only in evaluating the presence of the contaminants in the environment but also in determining their bioaccumulation and their effect on the exposed organisms.  相似文献   

4.
The effects of a recent bunker oil spill on the marine environment were assessed through investigation of the rocky shore fauna, phytoplankton population and macrobenthic communities over a study period of 150 days. In addition, toxicity experiments were carried out in the laboratory to ascertain the toxic effects of the oil-plus-dispersant on selected test organisms. The impacts of the spill on the marine fauna were minimal with no visible reduction in species and individual numbers. Possible reasons were the small amount of oil spilled, the rapid containment and dispersion in the clean-up operations, and the less toxic effects of the heavy bunker oil. On Hong Kong shores, the limpets can be identified as indicator species to oil pollution. A quick survey of the limpet fauna on the rocky shores immediately after a spill provides an initial assessment of the impacts on the shoreline. However, faunal recovery over a long-term period may be difficult to assess in view of the lack of baseline data on most of the marine biological communities in Hong Kong waters.  相似文献   

5.
Ecological effects of weathered and unweathered Louisiana crude oil spilled in eastern coastal plain estuaries were evaluated at all trophic levels and the major chemical components of the oil were followed through selected components of the ecosystem for 36 months.The study site consisted of a natural estuarine marshcreek habitat off the York River, Virginia, modified by the construction of retaining walls to form aquatic and marsh areas in each experimental unit. Each system was closed on all sides with the exception of an opening below the level of lowest tide to allow communication with tidal flow. Five experimental units were constructed, each having a surface area of about 810 m2, containing 695 m2 of marsh, 100 m2 of open water and 15 m2 of intertidal mud flat. The most upstream unit served as the control and the four downstream units received dosages of fresh and weathered crude oil. In addition, biological sampling in the open marsh and creek areas was conducted to provide an estimate of the effects of containing the marsh.Five hundred and seventy liters of fresh South Louisiana crude were added to each of the two downstream experimental enclosures approximately three hours into flood tide and were completed in 1 h. The weathered oil was similarly applied to the upstream units 3 days later.The weathered oil was not visible one week after the spill except as coatings on marsh grass blades, while the fresh crude remained for over three weeks. Plankton populations recovered within a week, and fish mortalities, which were most pronounced in the weathered oil unit, ceased after 10 days.Reductions in standing crops of marsh grasses were most pronounced the year following the spills, when peak biomass in the control exceeded the spill units by a factor of three. Recovery progressed further in the second year with peak biomass in the oiled units being about 70% of the control. The third year following the spill, recovery was nearly complete.Benthic populations were dominated numerically by oligochaetes. Significant reductions in populations of this dominant organisms and in populations of polychaetes and amphipods were demonstrable for a period of three years although most of the populations have shown definite signs of recovery.  相似文献   

6.
基于2002~2016年的省级面板数据,以农业水资源利用过程中的化肥源面源污染、厩肥源面源污染、灌溉过程碳排放及农药流失作为非合意产出,构建了以"蓝水-绿水"为中心的水资源分析框架,借助SBM模型和Malmquist-Luenberger指数,探析我国农业水资源利用过程的绿色技术进步情况,利用空间面板模型重点考察绿色技术进步、农业经济发展水平与农业水资源利用过程的污染排放之间的关系。化肥源面源污染排放量和农药流失量均表现出空间聚集的特性;在其他投入和产出不变的的既定条件下,促进农业水资源利用过程中的绿色技术进步能够缓解农业污染的局面;将农药流失污染作为非合意产出的农业水资源利用绿色技术进步带来的环境污染减排积极影响更强;农业经济发展水平与4类污染排放分别体现为倒N型、倒U型、正N型和倒N型的关系,随着农业经济发展水平的提升,我国绝大多数地区仍处于农药、化肥粗放使用的倒N型的上升阶段,农药流失和化肥施用引起的面源污染情况仍在加剧,农业经济发展水平与厩肥还田造成的面源污染相分离的状态逐渐消失,而农业水资源利用过程中产生的碳排放污染情况则不容乐观,大部分地区农业灌溉所产生的碳排放面临快速上升的趋势。  相似文献   

7.
首先建立了一套基于非结构网格的长江口-杭州湾二维垂向平均潮流数学模型,又基于最新的实测资料重点对南支水域流速、流向和水位进行验证,充分证实了模型的可靠性。在潮流模型可靠的基础上为MIKE21 SA(溢油模块)提供水动力基础数据,建立了一套基于欧拉 拉格朗日体系的“油粒子”追踪技术,综合考虑油膜扩展、输移和风化过程的长江口溢油行为与归宿预测模型。并对长江口夏季和冬季大潮溢油事故发生后取水口油膜厚度的变化及油膜运动路径进行了模拟预测。研究表明:油膜在长江口受到往复流形式的涨落潮交替作用,油膜沿深槽向下游震荡漂移;〖JP2〗油膜在纵向上逐渐被拉伸,形成窄长的油带,覆盖面积逐渐增大;油膜的运动轨迹除了受到涨落潮流的主控外还易受风况和长江口水下地形等影响;夏季溢油对3个水库均有不同程度的影响,冬季溢油只威胁到陈行水库的取水;夏季油膜蒸发量大于冬季  相似文献   

8.
Oil spill response, whether planned by government agencies, oil spill cooperatives or individual companies, can be planned and carried out with the goal of minimizing ecological impacts, not merely removing visible oil. Two oil spill cooperatives on the west coast are implementing such planning. First, a coastal survey was conducted in the cooperative's area of responsibility. Physical processes and habitat types were examined. Oil spill cleanup guidelines were written for each habitat type. Biologically sensitive areas, those sites most vulnerable to oil spill impacts, were identified. Strategies were developed to protect most sensitive areas, i.e., prevent spilled oil from reaching them. Protection is the preferred option because it prevents both the impact of the oil and subsequent cleanup activities. Protected areas can often serve as repopulation centers for surrounding sites that may have been impacted. If minimizing ecological impact is to be a prime focus of oil spill response, ecologists should be involved in both the planning before and the field efforts during such spill events.  相似文献   

9.
The shipwreck of the Amoco Cadiz supertanker on the rocks of the Brittany Coast of France (March, 1978) was one of the most disastrous oil spills ever recorded. The crude oils discharged in the marine environment were light petroleums. The distribution and the evolution of the oil pollution in the marine environment was examined. Chemical studies were limited to an overall estimate of the oil content to assess the importance and the extent of the pollution at the surface, in the water column, and in the sediment. UV fluorescence spectroscopy was used to detect oil in the seawater samples and IR spectrophotometry was used to analyze the sediment samples. Hydrocarbon concentrations in seawater ranged from 0.5 μ/1 to more than 100 μg/1. The oil spill has affected a very large section of the western English Channel. The diffusion of the hydrocarbons into the water column was observed. The evolution of the seawater pollution was followed, and the half-life of hydrocarbons in subsurface water was found to be between 11 and 28 days in different areas. One month after the disaster, the marine sediments were contaminated in the areas reached by the drifting slicks. The highest accumulation of petroleum in the sediments was located in the sheltered coastal environments. The natural decontamination process was found to be related to the nature of the sediment and the energy level of the geographic zone.  相似文献   

10.
重庆市主城区空气污染天气特征研究   总被引:1,自引:0,他引:1  
利用2003~2008年重庆市主城区大气污染监测资料,分析了轻度污染以上天气的变化特征。结果表明重庆主城区的主要污染物为PM10,PM10浓度具有独特的“双峰双谷”日变化特征;污染天气具有明显的季节特征,主要污染期为秋末到初春;污染天气具有连续性特征,污染天气持续时间尺度主要集中在2~7 d;污染天气过程具有典型的大气环流和天气特征,本地地面天气类型主要以低压或均压场为主,中高纬度高空以纬向环流或西北气流为主,天气以阴天或阴晴相间为主;污染天气过程中本地气象要素变化呈现规律性,地面24 h气压变化总趋势为负变压,24 h变温为正变温,平均相对湿度维持在72%~85%,风速的变化趋势不大,基本维持在1~2 m/s,低层逆温明显。污染天气过程结束时气压明显回升,温度显著下降,相对湿度显著增加。  相似文献   

11.
张家界市旅游生态安全评价及障碍因子分析   总被引:1,自引:0,他引:1  
开展旅游生态安全研究对旅游地协调生态环境保护与旅游业发展的关系具有重要意义。基于2001~2014年张家界市旅游生态安全的相关数据,从威胁、质量、调控3方面构建了张家界市旅游生态安全评价的“TQR”指标体系,并运用灰色关联投影法及障碍度模型对其旅游生态安全状况及主要障碍因子进行了分析。结果表明:总体上,2001~2014年,张家界市的旅游生态安全灰色关联投影值呈波动上升态势,但幅度有限,旅游生态安全水平未得到根本提升,除2003年外,安全状况均处于“一般”水平;就各子系统而言,2001~2014年,张家界市旅游生态安全威胁系统的安全状况由“一般”下降到“较不安全”,质量系统除2003年外均处于“较安全”水平,调控系统的安全状况由“较不安全”提升到“较安全”;2001~2014年,影响张家界市旅游生态安全的主要障碍因子有一定变化,早期的威胁主要为生态用地被占用、污水处理水平较低、从业人员素质不高等因素,近期则在游客密度控制、旅游资源利用强度调控、生态用地保护及污染减排等方面面临的压力越来越大。  相似文献   

12.
In this paper, results are reported on the concentrations and activity ratios of 137Cs, 239+240Pu and 238Pu in soils, lichen and bottom sediments collected at the peaceful underground nuclear explosion sites "Craton-3" and "Crystal" (Republic of Sakha (Yakutia), North-East Siberia). At the "Craton-3" site, 239- 240Pu concentrations in the range 6.2 mBq/g to 5.9 Bq/g in surface soils (0-5 cm) and 239+240Pu concentrations up to 7.4 Bq/g in lichen were observed. The 137Cs concentration in measured soils range from 0.52 to 216 Bq/g for the near-plume and from 1.65 to 21.5 Bq/g for the far-plume. In lichen, 137Cs concentration varied from a global background level up to 251 Bq/g. Radioactive contamination at "Crystal" demonstrates an extremely irregular distribution of 239,240Pu and 137Cs in environmental samples taken at locations within 150 m radius of the site. Further work on compiling detailed maps of radioactive contamination of the territory around "Craton-3" and "Crystal" is discussed.  相似文献   

13.
工业生产是现代物质财富的主要来源,同时也是带来环境污染的重要产业。本文对中国工业增长的绿化度进行了考察。首先采用层次分析法测度2005-2009年中国各地区环境污染综合指数,结果表明2005-2009年这5年间全国大多数地区环境污染指数都有不同程度上涨,平均环境污染指数从2005年的0.208上涨到2009年的0.267,就地区差异而言,环境污染指数呈现东高西低的特征,东部地区环境污染指数平均为0.340,而中部地区和西部地区分别为0.241和0.154,这与东部地区工业较为发达存在密切关系,也印证了中国经济发展仍存在较为明显的粗放式特征;其次,应用DEA方法在综合考虑环境污染和能源消耗问题的基础上测度2005-2009年中国各地区工业增长绿化度,结果表明东部地区工业绿化度明显优于中西部地区,东部地区工业绿化度平均为0.689,远高于中部地区的0.435和西部地区的0.496,而且,"十一五"以来,东部地区工业绿化度上升趋势明显,说明东部地区工业增长正在积极向绿色转型;论文还应用TOBIT回归分析法对影响中国工业绿化度的因素进行分析,研究表明技术进步、结构升级、经济开放都会对工业绿化度产生积极的效应。因此,为促进工业绿色增长中国需要进一步为技术的研发、扩散搭建顺畅的渠道;积极推动产业融合,获得协同收益;有效吸引清洁外资,开展绿色生产。  相似文献   

14.
Sublethal toxicity of the Prestige oil spill on yellow-legged gulls   总被引:1,自引:0,他引:1  
The Prestige oil spill in November 2002 is considered the biggest large-scale catastrophe of its type in Europe, thousands of seabirds dying in the subsequent months. Here, the total concentration of 16 polycyclic aromatic hydrocarbons (TPAH) was measured in the blood cell fraction of adult and chick yellow-legged gulls (Larus michahellis) from unoiled and oiled coastal areas in North Western Spain. In addition, hematocrit, plasma metabolites, electrolytes and enzymes, as well as body mass were determined in the same individuals. Our results strongly suggest the presence of health damages of sublethal nature in adult gulls breeding in oiled colonies 17 months after the Prestige oil spill. This is supported by the following evidences: (1) gulls sampled in unoiled and oiled colonies differed in blood TPAH levels, (2) gulls sampled in unoiled and oiled colonies differed in several blood parameters indicative of physiological disorders, and (3) TPAH in blood was significantly related to several of these parameters. Differences in the level of asparatate aminotransferase (AST), gamma-glutamyl transferase (GGT), total protein, glucose and inorganic phosphorus suggest damages on some vital organs (i.e. liver and kidney) in adult birds from oiled areas. Meanwhile, chicks presented weaker effects than adults, showing only between-area differences in hematocrit. Since TPAH levels in blood did not differ between both age-groups, the stronger effects on adults should be due to their longer exposure to these pollutants and/or to severe exposure in the months following the spill. The presence of PAHs in chicks indicates that these pollutants were incorporated into the food chain because nestlings would have been only exposed to contaminated organisms in the diet (e.g. fishes and crustaceans). Our findings support the view that PAHs may deeply alter the physiology of seabirds, and emphasize the necessity of quantifying the circulating levels of these compounds in order to evaluate the sublethal effects associated to large oil spills.  相似文献   

15.
In 2010, the global burden of foodborne diseases was 33 million Disability-adjusted life years, and 40 % of this burden was for children under 5 years old (Havelaar et al. 2015). Our study site was informal public markets within Mzuzu, Malawi, visited between September and December 2015, during the dry season. From these markets, fresh vegetables, leafy greens (n = 85), tomato (n = 85), and green pepper (n = 35) were analyzed for Escherichia coli. The prevalence of E. coli was highest on leafy greens; it was found in 74 (87 %) of the 85 samples. The prevalence of E. coli in green peppers was found in 2 (6 %) of the 35 samples. The prevalence of E. coli was lowest on tomatoes; it was found in only 1 (1 %) of the 85 samples. The lack of adequate water and sanitation infrastructure in market areas may be contributing to the bacteriological contamination of fresh produce. Providing venders with free access to market area toilets containing hand-washing facilities with soap and wash water with a chlorine solution may reduce bacterial contamination of fresh produce. Universal and sustainable access to water and sanitation services must include informal public market areas to reduce diarrheal diseases transmitted through food within Sub-Saharan Africa countries.  相似文献   

16.
Specific 85Kr activity is mapped from 264 domestic and municipal wells sampled during 2002-2004 in the Royal watershed (361 km2), Maine. Gas samples are collected at 20 m, 40 m, and > 50 m interval depths within the unconfined aquifers. Gas extraction for 85Kr from wells is obtained directly via a wellhead methodology avoiding conventional collection of large sample volumes. Atmospheric 85Kr input to the recharge environment is estimated at 1.27 Bq m(-3) by time-series analyses of weighted monthly precipitation (2001-2004). Numerical simulation of Kr gas transport through the variable unsaturated zones to the water table suggests up to 12-year time lags locally, thus biasing the 85Kr groundwater ages. Apparent 85Kr ages suggest that approximately 70% of groundwater near 20 m depth was recharged less than 30 years BP (2004). Mass-age transport modeling suggests that post mid-1950s recharge penetrates to part of the basin's floor and that older groundwater seeps from the underlying fractured bedrock may occur.  相似文献   

17.
Vertical distributions of 137Cs have been determined in vegetation-soil cores obtained from 30 different locations around two underground nuclear explosion sites--"Crystal" (event year - 1974) and "Kraton-3" (event year - 1978) in the Republic of Sakha (Yakutia), Russia. In 2001-2002, background levels of 137Cs surface contamination densities on control forest plots varied from 0.73 to 0.97 kBq m(-2) with an average of 0.84+/-0.10 kBq m(-2) and a median of 0.82 kBq m(-2). 137Cs ground contamination densities at the "Crystal" site ranged from 1.3 to 64 kBq m(-2); the activity gradually decreased with distance from the borehole. For "Kraton-3", residual surface contamination density of radiocaesium varied drastically from 1.7 to 6900 kBq m(-2); maximal 137Cs depositions were found at a "decontaminated" plot. At all forest plots, radiocaesium activity decreased throughout the whole vertical soil profile. Vertical distributions of 137Cs in soil for the majority of the plots sampled (n=18) can be described using a simple exponential function. Despite the fact that more than 20 years have passed since the main fallout events, more than 80% of the total deposited activity was found in the first 5 cm of the vegetation-soil cores from most of the forested landscapes. The low annual temperatures, clay-rich soil type with neutral pH, and presence of thick lichen-moss carpet are the factors which may hinder 137Cs transport down the soil profile.  相似文献   

18.
1ScopeIn the Sun Jia Catchment several gauging in-stallations are carefully put up to elucidate the hy-drology and the matter fluxes through the catch-ment.At present,it is already possible to quantifydistinct spatial differences in principal water flu-xes.The setup bears the potential to further deep-en the understanding of the small scale processesinvolved in lateral water fluxes and soil erosion.Multi-point monitoring of soil water potentials atvarious soil depths together with hydrograph…  相似文献   

19.
Long-term trends of 137Cs and 40K concentrations in meadow grass and soil-plant transfer data at eight different sites in Upper Austria are presented. Geometric means of 137Cs TF-data and Tagg values vary between 0.03-1.06 and 0.0005-0.0184 depending on site, respectively. 40K results are less variable with TF values covering a range of 0.31-2.01. Only at one site was a significant decrease of 137Cs concentration (decay-corrected) in meadow vegetation observed during the observation period 1992-1999. Seasonal trends of 40K and 137Cs were investigated at one site in 1996. Both elements show decreasing concentrations in plants from beginning of May-July, followed by a peak in September. Although this pattern was not very pronounced, there are some hints that it may explain deviations of long-term trends in 137CS levels in grass caused by unusual weather conditions as indicated by phenological climate data (beginning of sweet cherry and black elder blossoming). Finally, TF values were correlated with soil characteristics, revealing a negative correlation of radiocaesium soil-plant transfer with soil pH, exchangeable and extractable fractions of Mg, Ca and Na as well as a positive correlation with exchangeable Al.  相似文献   

20.
Massanjore reservoir (area ~67 km2) located 84 km downstream from the most distant upstream source capacitates 620,000,000 m3 of water, and regulated flow characters are highly responsible for dam downstream alteration of hydrological, sedimentological and geomorphological characteristics of Mayurakshi River. In dam after condition, monsoon water level (mean water level during monsoon months) and pre-monsoon water level (mean water level during pre-monsoon months, i.e., March–May) have attenuated about 0.56 and 0.32 m, respectively. Maximum duration of high flow period during monsoon has reduced up to 16.5 %; coefficient of variation of diurnal fluctuation of water level during monsoon has increased from 31 to 47 %. Suspended sediment load in Mayurakshi River is reduced to 34 % in dam after period as recorded at Narayanpur gauge station. Average suspended sediment load has decreased even after Tilpara barrage construction from 4.960 to 4.350 mg/L. Average suspended sediment load is 7.875 mg/L in the sites of dam upstream course, and this average is only 4.46 mg/L in different sites of dam downstream course. Volume of discharge has decreased up to 11.3 % during monsoon time in dam after condition. Such reduction in discharge volume in turn has reduced about 24.6 % bed load-carrying capacity. As a result, huge deposition within channel invigorated channel bed aggradations (average 73.6 cm up to Saspara, site 14 at Fig. 1) in dam after condition. Narrowing of active channel, coarsening of channel bed materials, lowering of lateral stability, accelerating rise of braiding index, mixed response of the channel adjustment of the tributaries to local scale positive or negative base level change due to river bed aggradations and degradation, etc. signify the morphological alteration of dam downstream course.
Fig. 1 Mayurakshi River basin indicating Massanjore Dam, Tilpara barrage and sample working sites
  相似文献   

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