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1.
Beached bird surveys provide an important tool for monitoring the level of oil pollution at sea, which is the most significant observable cause of death for a large number of waterbird species and pose a serious threat to wintering seabird populations. Linear regression analyses of oil rates from the Danish 22 year dataset show a decline in the oil pollution level in offshore areas of the eastern North Sea and Skagerrak and in near-shore parts of the Kattegat; but a worsening in the offshore areas of the Kattegat. These results raise concern for species such as common scoter, velvet scoter, eider and razorbill, for which the Kattegat serves as a globally important wintering area. It is recommended that surveillance for oil spills is intensified in inner Danish waters, and that action is taken to make responses towards offenders faster, and penalties for oil seepage higher.  相似文献   

2.
Strandings of oiled seabirds are used to signal the problem of chronic oil pollution. Species-specific oil rates reflect the risk for marine birds to become oiled at sea. High oil rates were characteristic for seabirds common in areas with frequent oil spills; low oil rates for birds wintering away from the busiest shipping lanes. Declining trends in oil-rates were found, reflecting a reduction in the amount of oil intentionally discharged over the past 50 years. Spatial patterns in the risk to become oiled could be identified, when the winter distribution patterns of the affected birds were incorporated in the analysis. Declines in oil rates were most pronounced in coastal birds. These trends were consistent with tendencies to police nearshore waters more effectively than offshore waters. While levels of chronic oil pollution are much reduced, future emphasis should be to reduce chronic oiling more effectively in offshore waters.  相似文献   

3.
Lagrangian passive tracer transport simulations covering the 46-year period 1958-2003 were utilized to compare the exposures of different parts of the German North Sea coast to ship-related chronic oil pollution. Assuming the spatial distribution of oil releases to be proportional to estimated ship traffic density, detailed drift reconstructions allowed for the reconstruction of wind-induced inter-annual variations in coastal pollution. For the winter months, a statistical relationship between simulated advective transports and prevailing sea surface pressure fields was established via Canonical Correlation Analysis. Wind effects were found to be more important for the northern (Schleswig-Holstein) than for the southern (Lower Saxony) part of the German North Sea coast. For Schleswig-Holstein, simulations showed consensus with beached bird survey data from this region. Proper identification of weather-driven inter-annual and spatial variations in monitoring data helps to avert misjudgments with regard to trends in the general level of chronic oil pollution.  相似文献   

4.
This paper examines the use of exploratory spatial analysis for identifying hotspots of shipping-based oil pollution in the Pacific Region of Canada’s Exclusive Economic Zone. It makes use of data collected from fiscal years 1997/1998 to 2005/2006 by the National Aerial Surveillance Program, the primary tool for monitoring and enforcing the provisions imposed by MARPOL 73/78. First, we present oil spill data as points in a “dot map” relative to coastlines, harbors and the aerial surveillance distribution. Then, we explore the intensity of oil spill events using the Quadrat Count method, and the Kernel Density Estimation methods with both fixed and adaptive bandwidths. We found that oil spill hotspots where more clearly defined using Kernel Density Estimation with an adaptive bandwidth, probably because of the “clustered” distribution of oil spill occurrences. Finally, we discuss the importance of standardizing oil spill data by controlling for surveillance effort to provide a better understanding of the distribution of illegal oil spills, and how these results can ultimately benefit a monitoring program.  相似文献   

5.
Organic matter is related closely to mineralization of Lannigou gold deposit in southwestern Guizhou, China. Regionally, the distribution of organic carbon agrees well with that of faults within which gold deposits are hosted. Studies on organic petrology show that pyrobitumen, which is related most closely to mineralization, adheres to quartz vein or fills quartz veinlet. Proton-induced X-ray emission (PIXE) analysis shows an evident abundance of Au in pyrobitumen. Pyrobitumen paragenetically associates with pyrite and arsenopyrite which are the main carrier minerals of Au. The thermal simulation experiment indicates that about 99% of Au will be concentrated in oil phase in the coexisting system of oil and brine and rock. The role of crude oil in ore-forming process is: as carrier of Au, crude oil moves upwards, and undergoes thermal decomposition and thermochemical reduction when it encounters the oxidizing fluid within the Trassic turbidity; Au is thus released from crude oil, reduced and precipitated. Project supported by the Climbing Project (No. PA30) and the National Natural Science Foundation of China (Grant No. 49673190).  相似文献   

6.
Malaysian coasts are subjected to various threats of petroleum pollution including routine and accidental oil spill from tankers, spillage of crude oils from inland and offshore oil fields, and run-off from land-based human activities. Due to its strategic location, the Straits of Malacca serves as a major shipping lane. This paper expands the utility of biomarker compounds, hopanes, in identifying the source of tar-balls stranded on Malaysian coasts. 20 tar-ball samples collected from the east and west coast were analyzed for hopanes and polycyclic aromatic hydrocarbons (PAHs). Four of the 13 tar-ball samples collected from the west coast of Peninsular Malaysia were identified as the Middle East crude oil (MECO) based on their biomarker signatures, suggesting tanker-derived sources significantly contributing the petroleum pollution in the Straits of Malacca. The tar-balls found on the east coast seem to originate from the offshore oil platforms in the South China Sea. The presence of South East Asian crude oil (SEACO) tar-balls on the west coast carry several plausible explanations. Some of the tar-balls could have been transported via sea currents from the east coast. The tankers carrying SEACO to other countries could have accidentally spilt the oil as well. Furthermore, discharge of tank washings and ballast water from the tankers were suggested based on the abundance in higher molecular weight n-alkanes and the absence of unresolved complex mixture (UCM) in the tar-ball samples. The other possibilities are that the tar-balls may have been originated from the Sumatran oil fields and spillage of domestic oil from oil refineries in Port Dickson and Malacca. The results of PAHs analysis suggest that all the tar-ball samples have undergone various extent of weathering through evaporation, dissolution and photo-oxidation.  相似文献   

7.
应用环境磁学方法研究了2008年奥运会前后北京市朝阳区大气降尘及对照点表土样品的磁学特征.结果表明,所有样品中载磁矿物主要为低矫顽力的亚铁磁性矿物(主要为磁铁矿).但大气降尘样品的磁性颗粒粒度较表土偏粗;磁性矿物含量高于表土样品,大气降尘除来自于自然源外,更多为来自于人为因素的结果.大气降尘磁化率与空气污染物浓度随时间的变化曲线特征一致,说明大气降尘样品的磁学监测可以快速、准确地反映城市空气污染程度及其变化,同时揭示出北京市朝阳区大气降尘样品夏季主要来源于工业和交通,冬季主要受控于集中供暖期间煤燃烧排放的废气.快速的磁化率测量可以对空气污染指数有良好的指示作用.环境磁学参数随时间的变化特征显示,奥运期间各项污染物临时减排措施落实到位,对空气质量明显改善发挥了根本性作用.  相似文献   

8.
The current study was designed to validate the biomarkers of sewage pollution in Mozambique Tilapia (Tilapia mossambica, Peters) reared in sewage treatment plant (STP) effluent in Ras Al Khaimah, United Arab Emerates, before and following depuration/detoxification. Cellular biomarkers, cholinesterase activity using acetylcholine as a substrate (acetylcholinesterase AChE) and reduced glutathione (GSH) and hepatosomatic index (HSI) were investigated in fresh water fish, Tilapia, raised in a fish farm (Group I/Clean, as Control), treated sewage water/TSW (Group II/Sewage) and thereafter exposed to fresh water in an aquarium for 6 weeks (Group III/Depurated) for depuration. The results showed significantly lower levels of AChE activities in liver (26% p < 0.01) and muscle (30% p < 0.01) of the fish reared in the STP water (Group II/Sewage) as compared to those recorded in the fish from fish farm (Group I/Clean). The depressed AChE level was fully restored in the muscle but partially in the liver after depuration (Group III/Depurated). In contrast, GSH levels were significantly raised in both liver (1.3-fold p < 0.01) and muscle (4-fold) of Group II fish as compared to Group I (control) fish raised in fish farm and following depuration in fresh water (Group III/Depurated) elevated GSH level in liver restored to control values, while remained unchanged in muscle. The average hepatosomatic index (HSI = weight of liver × 100/total fish weight), an indicator of hepatomegaly, in the Group II fish reared in TSW was also significantly higher than that in the reference Group I fish, but decreased to control level in Group III fish following depuration. This study suggests the importance of cellular biomarkers, AChE, GSH and hepatosomatic index in monitoring the impact of sewage water pollution on fish caused by a complex mixture of chemico-biological contaminants and its mitigation following depuration, an effective mean of fish detoxification.  相似文献   

9.
唐山地震前不同区域油水井异常变化及其机理分析   总被引:1,自引:0,他引:1  
对唐山地震前胜利、大港、辽河3个油田的油井和渤中2井的资料以及北京附近部分水井的资料进行整理和分析,描述了油水井的短期和临震异常特征;分析了唐山地震前同一地区和不同地区间的油水井前兆异常之间的关系,对油水井异常变化的机理进行了研究和分析,认为不同的油水井前兆异常是由于唐山地震孕震过程中造成的不同地区的应力状态不同所致,油水井前兆异常可以用来监测和预报地震。  相似文献   

10.
The withdrawing Arctic ice edge will facilitate future sea transport and exploration activities in the area, which calls for the establishment of relevant cold water monitoring species. The present study presents first results of field baseline levels for core oil pollution biomarkers in Polar cod (Boreogadussaida) sampled from pristine, Arctic waters. Furthermore, biomarker response levels were characterized in controlled laboratory exposure experiments running over 2 weeks. Fish exposed to a simulated petrogenic spill (1 ppm dispersed, crude oil) exhibited elevated hepatic EROD activity, bile PAH-metabolites, and hepatic DNA-adducts, whereas male individuals exposed to simulated produced water (30 ppb nonylphenol) exhibited a strong induction of plasma vitellogenin. In conclusion, the results demonstrated low and robust biomarker baseline levels that were clearly different from exposure responses. In combination with its high abundance and circumpolar distribution, the Polar cod seems well qualified for oil pollution monitoring in Arctic waters.  相似文献   

11.
粉煤灰经工厂废气排放进入大气,对人类健康和生态系统都造成了无法弥补的破坏.本文选取具有高空间分辨率优势的树叶作为收集粉煤灰的载体,对临汾市大气中可吸入颗粒物进行磁学参数和重金属含量监测.结果表明,磁化率最大值出现在工厂污染源附近,磁化率空间分布呈现随污染源距离增加而降低的趋势.工业区收集到的磁性颗粒以低矫顽力、粗粒度的磁铁矿为主.夏季磁性矿物来源单一,主要为人为影响.冬季大气中悬浮的磁性颗粒有部分来自于西北风/北风的自然尘降.同一采样点磁化率随时间变化特征表明,树叶的磁学性质可以灵敏和有效地反映较短时期内大气污染的现状.统计分析表明磁化率和重金属元素(铁,铬,镍,铜,铅,钴)之间存在显著相关性.污染负荷指数用于评估研究区域内重金属各元素综合污染的程度.结果显示,在废弃的旧工业区附近无大气污染指示,但在运营中的工厂集中的地区,大气均受到严重污染.污染负荷指数与表征磁性矿物含量的磁化率呈相关性(r2=0.66),因此树叶的磁性参数可以作为大气重金属污染的替代指标.  相似文献   

12.
The vertical distribution of trace metals in sediment cores was investigated to evaluate the extent and the historical record of metal pollution over 30 years in the artificial Lake Shihwa in Korea. A marked increase of trace metals after 1980 was observed due to the operation of two large industrial complexes and dike construction for a reclamation project. There was a decreasing trend of metal concentrations with the distance from the pollution source. The enrichment factor and pollution load index of the metals indicated that the metal pollution was mainly derived from Cu, Zn and Cd loads due to anthropogenic activities. The concentrations of Cr, Ni, Cu, Zn, As and Pb in the upper part of all core sediments exceeded the ERL criteria of NOAA. Our results indicate that inadequate planning and management of industrialization and a large reclamation project accomplished by dike construction have continued to strongly accelerate metal pollution in Lake Shihwa.  相似文献   

13.
Combined evidence from the outcrop and the fluid inclusion assemblage (FIA) analysis indicates that there exist two episodes of fluid flow controlled by the tectonic activity. The first episode was recorded mainly in the reservoir rock of the Honghuayuan Formation,representing the fluid flow of hydrocarbon charging. The second episode occurred mainly along the fault systems,representing the fluid move-ment when the ancient oil reservoir was destroyed. The host mineral morphology,homogeneous tem-perature,and salinity of the FIAs record an episodic fluid movement. Characters of high homogenous temperature,low salinity and a quick temperature variation of the first episode fluid flow may indicate an early-stage fluid eruption,and correspondingly,fine-grained calcite was formed. Temperature of the erupted fluid tended to decrease during its mixing with the upper formation fluid and finally had the same temperature as the upper formation. From then on,the temperature was rather steady and fa-vored the growth of the coarse calcite. Due to this character of the temperature variation of the episodic fluid flow,we can use the homogenous temperature of the FIA of the coarse calcite to date the forma-tion and the destruction time of the Majiang ancient oil reservoir. Episodic fluid flow was known for its inhomogeneous trapping,which resulted in the failure of dating according to the burial history. But taking a close look at its temperature variation,we think that the latest stage of fluid flow,characterized by steady state temperature and grow of the coarser crystals,can be used for dating. It will be of great value if this method is proved to be effective. The formation and the destruction time of the Majiang ancient oil reservoir were dated to be in the Indosinian Period and the late Yanshan-early Hymalayan Period respectively. This conclusion is in great discrepancy with the common accepted idea that the Majiang ancient oil reservoir was formed and destroyed during the Caledonian tectonic movement. Even so,this paper further discussed its reliability from the view of the source rock evolution and also the local tectonic evolution.  相似文献   

14.
Produced water is one of the largest waste products routinely discharged into the ocean from offshore oil and gas platforms. This study analyzed bacterial communities and metals in the produced water, surrounding seawater, and sediment around the Thebaud platform. The bacterial community within the produced water was different from the seawater (SAB = 13.3), but the discharge had no detectable effect on the bacterial communities in the seawater (SAB > 97). In contrast, genomic analysis of sediments revealed that the bacterial community from 250 m was different (SAB = 70) from other locations further from the discharge, suggesting that the produced water had a detectable effect on the bacterial community in the sediment closest to the discharge. These near-field sediments contained elevated concentrations of manganese and iron that are associated with the produced water effluent. The results suggested that the discharge of produced water has influenced the bacterial community structure of sediments adjacent to the platform.  相似文献   

15.
Neural network techniques combined with Geographical Information Systems (GIS), are used in the spatial prediction of nitrate pollution in groundwaters. Initially, the most important parameters controlling groundwater pollution by nitrates are determined. These include hydraulic conductivity of the aquifer, depth to the aquifer, land uses, soil permeability, and fine to coarse grain ratio in the unsaturated zone. All these parameters were quantified in a GIS environment, and were standardized in a common scale. Subsequently, a neural network classification was applied, using a multi‐layer perceptron classifier with the back propagation (BP) algorithm, in order to categorize the examined area into categories of groundwater nitrate pollution potential. The methodology was applied to South Rhodope aquifer (Thrace, Greece). The calculation was based on information from 214 training sites, which correspond to monitored nitrate concentrations in groundwaters in the area. The predictive accuracy of the model developed reached 86% in the training samples, 74% in the overall sample and 71% in the test samples. This indicates that this methodology is promising to describe the spatial pattern of nitrate pollution. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

16.
Imposex, or the presence of a pseudopenis in female snails, is quantified by comparing the length of the female pseudopenis with the male penis. However, many muricid gastropods in the Malayan archipelago possess penes that are flagellate and coiled, making linear measurement difficult under the microscope. In addition, it is unclear if penis length is dependent on shell size. Accurate assessment of penis size is a necessary step towards determining the severity of imposex (and implicitly, the amount of organotins from antifouling paints that is associated with this phenomenon). Two mangrove muricid gastropod species, Thais gradata and Chicoreus capucinus, were collected from six sites along the Johor Straits. Penis/pseudopenis length and area measurements based on digitalized camera lucida drawings were generally well correlated with penis/pseudopenis dry weight, although penis area appeared to be a marginally better variable than penis length for T. gradata. Penis dry weight was also well correlated with shell height in male T. gradata, while no significant correlation was detected for female T. gradata, suggesting pseudopenis size alone may be a better measure of imposex than the relative penis size index (RPSI) for this species. There was no obvious relationship between penis size and shell height for either sex in C. capucinus.  相似文献   

17.
Satoshi  Hirano  Yoshiaki  Araki  Koji  Kameo  Hiroshi  Kitazato  Hideki  Wada 《Island Arc》2006,15(3):313-327
Abstract   A drilling and coring investigation of the Sagara oil field, central Honshu, Japan, was conducted to contribute to the understanding of hydrocarbon migration processes in a forearc basin. Core samples were analyzed to determine lithology, physical properties (specifically gas permeability) and the characteristics of oil occurrence. Gas permeability values greater than approximately 10−11 m2 constitute the basic precondition for any lithology to serve as a potential fluid conduit or reservoir in the Sagara oil field. Cores recovered from the 200.6-m-deep borehole were primarily composed of alternating siltstone, sandstone and conglomerate, all of which are correlated to the late Miocene Sagara Group. Both sandstone and conglomerate can be classified into two types, carbonate-cemented and poorly to non-cemented, based on matrix material characteristics. Oil stains are generally absent in the former lithology and more common in the latter. Variations in physical properties with respect to gas permeability values are directly related to the presence and character of carbonate cement, with higher permeabilities common in poorly to non-cemented rocks. The relationships between lithology, oil-staining, cementation and permeability indicate that cementation preceded oil infiltration and that cementation processes exerted significant control on the evolution of the reservoir.  相似文献   

18.
The adsorption kinetics of carbamazepine, naproxen, and trimethoprim in aqueous solution by Amberlite? XAD‐7 has been studied. The influence of adsorbent dose (1–3 g/L), stirring rate (80–240 rpm), pH (2–9), temperature (20–60°C), and initial concentration (25–75 ppm) on the adsorption kinetics has been analyzed. The removal efficiency in the first 2 h reaches 85% for carbamazepine, 60% for naproxen, and 70% for trimethoprim. pH appears to be the most important factor conditioning the removal of these latter solutes, whereas carbamazepine adsorption seems to be independent of the pH of the adsorptive solution. Initial concentration and operation temperature moderately influence the adsorption process. Finally, stirring rate scarcely affects the process. The experimental data have been fitted to four kinetic models, namely pseudo‐first and pseudo‐second order, intra‐particle diffusion and Bangham's. The model providing the best fit is the pseudo‐second order one. Again, pH is the factor that affects the adsorption rate in a more remarkable manner although other parameters such as temperature and stirring rate also contribute to accelerate the removal of the solutes. Under the optimal operation conditions, Amberlite? XAD‐7 exhibits a promising ability for the removal of the pharmaceuticals under study.  相似文献   

19.
Natural Resource Damage Assessment (NRDA) procedures in the US involve the use of uniform federally approved rules and procedures to assess economic losses and/or address restoration of injured resources that result from spills of hazardous substances and/or oil and petroleum substances in waterways under US jurisdiction. This effort started in the 1980s and involves two federal agencies that have developed separate federally approved procedures and rules, the US Department of Interior (US DOI) and the US Department of Commerce, National Oceanographic and Atmospheric Administration (US DOC, NOAA). This paper provides a brief overview of the federal laws applicable to resource damage assessments in the US, review of NRDA rules and procedures, and progress to date regarding US cases.  相似文献   

20.
Mytilus edulis and Chlamys islandica were exposed to nominal dispersed crude oil concentrations in the range 0.015–0.25 mg/l for one month. Five biomarkers (enzymatic and cellular responses) were analysed together with bioaccumulation of PAHs at the end of exposure. In both species, PAH tissue residues reflected the exposure concentration measured in the water and lipophylicity determined the bioaccumulation levels. Oil caused biomarker responses in both species but more significant alterations in exposed C. islandica were observed. The relationships between exposure levels and enzymatic responses were apparently complex. The integrated biomarker response related against the exposure levels was U-shaped in both species and no correlation with total PAH body burden was found. For the monitoring of chronic offshore discharges, dose- and time-related events should be evaluated in the selection of biomarkers to apply. From this study, cellular damages appear more fitted than enzymatic responses, transient and more complex to interpret.  相似文献   

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