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1.
Invasive coral species of the genus Tubastraea have been increasingly recorded in Southwestern Atlantic waters since the 1980s. Their invasion and infestation are mainly related to port and oil exploration activities. For the first time the presence of Tubastraea tagusensis colonies is reported in Espírito Santo State, colonizing a port shore area, and incrusting oil/gas platform structures situated in the southern Abrolhos Bank, which is part of the most important coral reef system of the South Atlantic Ocean. Tubastraea colonies exhibit fast growth and high recruitment rates, and colonized 40% of the analyzed structures in just four years. The projection of port and oil/gas industry growth for the Espírito Santo State (more than 300%) highlights an alert to the dispersal of this alien species to natural areas.  相似文献   

2.
Sea anemones (Anthopleura elegantissima) can withstand submersion in Bunker C fuel oil for up to 1 h without visible adverse effects. The wet, mucus-covered tissues of the sea anemones may repel oil. During recovery, the sea anemones expand the column, evert the tentacles and reattach. A dahlia anemone (Tealia lofotensis) withstood immersion in oil for 15 min. The ability to withstand immersion in oil may confer an ecological advantage to sea anemones in contaminated areas.  相似文献   

3.
The general effects of the Eleni V oil spill on fisheries and intertidal organisms are described. There appears to have been little damage except by direct smothering. Oil hydrocarbon concentrations have been followed in a small intertidal population of mussels (Mytilus edulis) at Corton beach. Although the area became visually clean of oil, hydrocarbon concentrations in mussel flesh remained high 12 months after the spill and depuration rates in the laboratory were very slow. Shrimps (Crangon crangon) exposed to a water extract of beached Eleni V oil for 42 days showed no ill effects and little uptake of hydrocarbons. At the North Harbour site, where beached oil has not been disturbed, it appears that the fauna, used to oil contamination from other sources, has been little affected by the additional Eleni V oil.  相似文献   

4.
Mangroves are sensitive ecosystems of prominent ecological value that lamentably have lost much of their areas across the world. The vulnerability of mangroves grown in proximity to cities requires the development of new technologies for the remediation of acute oil spills and chronic contaminations. Studies on oil remediation are usually performed with in vitro microcosms whereas in situ experiments are rare. The aim of this work was to evaluate oil degradation on mangrove ecosystems using in situ microcosms seeded with an indigenous hydrocarbonoclastic bacterial consortium (HBC). Although the potential degradation of oil through HBC has been reported, their seeding directly on the sediment did not stimulate oil degradation during the experimental period. This is probably due to the availability of carbon sources that are easier to degrade than petroleum hydrocarbons. Our results emphasize the fragility of mangrove ecosystems during accidental oil spills and also the need for more efficient technologies for their remediation.  相似文献   

5.
The fate and effects of the spill of Eleni V heavy fuel oil in May 1978 have been followed at two sites; one a heavily-polluted area subject to mechanical clean-up and one an undisturbed site where oil remains. At the first site the mechanized clean-up, and re-sorting of beach material by winter storms, has left the area visually clean of oil. However, near-shore and interstitial waters still contain high concentrations of Eleni V hydrocarbons 12 months after the spill. At the undisturbed site there has been very little change in the appearance and chemical composition of the oil during this period.  相似文献   

6.
Studies have been made of the effects of exposure to various forms of crude oil on the righting behaviour of Paracentrotus lividus and its reactions towards the presence of oil. Prolongation of the righting response was recorded in animals exposed to contact with surface or sunken fresh crude oil or to their water soluble fractions. No such effect was recorded on exposure to weathered oils and results indicate that the more volatile components of crude oil were responsible for this effect. Paracentrotus showed no avoidance reaction to the presence of sunken oil in its vicinity. The likely ecological significance of these results is discussed.  相似文献   

7.
Crude oil spills, Hebei Spirit in South Korea, is considered as one of the worst environmental disasters of the region. Our understanding on activation of oil-degrading bacteria and resilience of microbial community in oil contaminated sites are limited due to scarcity of such event. In the present study, tidal flat sediment contaminated by the oil spill were investigated for duration of 13 months to identify temporal change in microbial community and functional genes responsible for PAH-degradation. The results showed predominance of previously known oil-degrading genera, such as Cycloclasticus, Alcanivorax, and Thalassolituus, displaying significant increase within first four months of the accident. The disturbance caused by the oil spill altered the microbial community and its functional structures, but they were almost restored to the original state after 13 months. Present study demonstrated high detoxification capacity of indigenous bacterial populations in the tidal flat sediments and its resilience of microbial community.  相似文献   

8.
The East Coast of Peninsular Malaysia faces the South China Sea and is vulnerable to oil pollution because of intense petroleum production activities in the area. The South China Sea is also a favored route for supertankers carrying crude oil to the Far East. Consequently, oil spills can occur, causing pollution and contamination in the surrounding areas. Residual oil spills stranded on coastal beaches usually end up as tar-balls. Elucidating the sources of tar-balls using a molecular marker approach is essential in assessing environmental impacts and perhaps settling legal liabilities for affected parties. This study utilizes a multimodal molecular marker approach through the use of diagnostic ratios of alkanes, hopanes, and polycyclic aromatic hydrocarbons (PAHs) to determine the source, distribution and weathering of tar-balls. Hopane ratios (e.g., C29/C30, and summation C31-C35/C30 ratios) were used to identify the sources of tar-balls. The weathering effects were distinguished by using alkanes, namely the unresolved complex mixture (UCM) and low molecular weight/high molecular weight (L/H) ratios. Similarly, PAHs were also used for the determination of weathering processes undergone by the tar-balls. This multimodal molecular marker gave a very strong indication of the sources of tar-balls in this study. For example, 16 out of 17 samples originated from South East Asian Crude Oil (SEACO) with one sample from Merang, Terengganu originating from North Sea Oil (Troll). The TRME-2 sample may have come from a supertanker's ballast water discharge. The second possibility is that the tar-ball may have been transported via oceanographic currents. All 'weathered' sample characterizations were based on the presence of UCM and other ratios. The multimodal molecular marker approach applied in this study has enabled us to partially understand the transport behavior of tar-balls in the marine environment and has revealed insights into the weathering process of tar-balls.  相似文献   

9.
南黄海残留盆地宏观分布特征研究   总被引：10，自引：9，他引：1       下载免费PDF全文
由于前新生代残留盆地具有埋深大、构造复杂的特点,采用综合地球物理研究方法成为圈划残留盆地宏观分布及预测残留盆地油气资源的重要方法技术．本文以南黄海地区为例,以重、磁数据为主体,以钻井、地震等高精度数据为先验信息做约束,采用带约束界面反演方法求取重力基底,同时根据求取的磁性基底计算了中、古生界的残余厚度,给出了前新生界残留盆地宏观分布特征．结合石油地质条件,圈划了油气资源有利区．研究结果表明南黄海北部坳陷北部和东北部中生界残余厚度较大,中部隆起与勿南沙隆起古生界残余厚度巨大,是较好的前新生代油气前景区．  相似文献   

10.
The toxic effects of crude oil, the dispersant, Corexit 7664, and mixtures of these on the respiration and mortality of two species of bivalve have been examined. A light Arabian crude is most toxic to one, Corexit is most toxic to the other. The susceptibility to oil of the mussel Brachidontes is also reflected in a significant depression of respiration rate at sub-lethal concentrations.  相似文献   

11.
The Castillo de Bellver incident resulted in the loss of between 160 000 and 190 000 t of crude oil. Not only was this the largest spill to date in South Africa, but it occurred near an area of great ecological sensitivity, and in the vicinity of important commercial fishing grounds. Despite this, observations during the spill and on subsequent surveys indicated that environmental damage was minimal. This can only be attributed to the favourable direction of the wind, which caused the slick to move offshore and into the Benguela current, thus allowing for its natural dispersion. Some concern remains over oil still trapped in the sunken stern section.  相似文献   

12.
On 27 February 1979 the tanker Antonio Gramsci grounded off Ventspils (USSR) in the Baltic Sea. Some 5000–6000 t of crude oil were spilled, and drifted towards the archipelago of Stockholm (Sweden) and Åland (Finland). About 500 t oil was mechanically recovered in the Åland area. The effects of the oil on the littoral communities were studied for two months after the spill, and for the benthic community the long-term changes were recorded for three years. The immediate effects were small in the uppermost littoral (the Cladophora belt), but in the lower littoral (the Fucus belt) severe effects were recorded. Meiofaunal densities decreased in crustacean and mollusc species, but remained stable for the total community. Macrofaunal long-term changes could not be linked to the oil spill. Thus the effects of the oil were rather small, although a large area was contaminated.  相似文献   

13.
Tidal recordings have been made with high-precision equipment at twenty-eight stations in the South East Asia and the South Pacific areas. Each station was occupied for five months or more. Amplitude factors (δ) and phase differences (α) of the principal tidal constituents exhibit a regional behaviour which results from the oceanic-tide interaction. At Alice Springs, Northern Territory, the middle point of Australia, the results based upon nine month's observations fit fairly well the Molodensky theory on the dynamical effects of the liquid core of the earth.  相似文献   

14.
Diet and feeding intensity of the portunid crab Polybius henslowii were studied during the spring of 2004 along Galician and Cantabrian continental shelves (NW Iberian Peninsula) between 78 and 287 m. The area had been affected by the Prestige oil spill in November 2002, with different sectors at different levels of pollution: highest in between Miño River and Cape Finisterre (MF) and from there to Estaca de Bares Point (FE) and lowest from Estaca to Cape Peñas (EP). From 37272 specimens collected in 59 bottom hauls, 342 were analysed for stomach fullness and diet composition. Stomach fullness was lower in FE, but with no significant differences among sectors. Diet was a mixture of pelagic and benthic prey: cephalopods (Ilex coindetti), brachyurans (P. henslowii) and polychaetes (Glycera sp.). Other prey were beloniform eggs and fish remains. Two stress markers were also studied in some specimens: Acetylcholinesterase (a neurotoxicity marker) varied among sampled areas, while lipid peroxidation (an oxidative stress marker) did not. Changes in trophic variables, distribution and density were analysed in relation to depth, surface and bottom T, surface Chl a from satellite imagery and tar aggregate concentration in sediments. Along Galician and Cantabrian coasts prey availability, linked to productivity level, seems to be the main factor affecting P. henslowii diet and distribution. Interannual abundance variability seems to be controlled by large-scale climatic conditions (NAO index). This natural variability masks possible effects induced by the oil spill.  相似文献   

15.
The effects of oil pollution on the sea anemone Actinia equina were investigated. Chronic pollution with 2.5 ml.l?1 crude oil resulted, for about seven weeks, in ejection of increased numbers of the young which are normally brooded within the gastric cavity. Subsequently the numbers of surviving young being produced fell to zero, and the ovaries were found to be regressed and lacking ova. The anemones were also more frequently observed with tentacles expanded and mouth open, but the response to food offered to the tentacles was slow or absent. In separate tests it was found that crude oil presented on filter paper to the anemones could act as a feeding inducer, but that it interfered with or diluted the action of natural feeding inducers present in fish muscle extract. These effects are comparable with those which oil pollution has been found by other workers to have upon other anthozoans—the corals.  相似文献   

16.
The fate and effects of Eleni V oil spilled in May 1978 have been followed until May 1980. At a mechanically-cleaned and exposed beach the hydrocarbon concentrations of inshore water and mussel tissue returned to background values between 300 and 400 days after the beaches became visually clean. Oil remaining on the surface of a protected beach still showed little degradation compared to oil buried in a disposal pit. Even on mobile beaches subject to high wave-energy, mechanical retrieval and clean-up of such a persistent heavy fuel oil is considered necessary unless its redistribution by wave action over adjoining beaches and into sediments is considered acceptable.  相似文献   

17.
我国南方碳酸盐岩广泛分布,具有巨大的油气资源潜力和勘探前景.全国油气资源战略选区调查与评价项目选择我国典型南方海相碳酸盐岩裸露区开展地震勘探技术攻关.针对该区地表灰岩普遍出露、激发弹性波能量转换少、散射噪音干扰严重等勘探难点,研究和应用了“宽线+折线”地震采集技术和与其配套的拟三维地震处理技术,能较好地压制噪音,提高剖面信噪比,在主要目的层得到了较好的成像效果,桂中1井钻探结果与地震勘探解释成果吻合较好,检验了该方法用于南方碳酸盐岩地区勘探的有效性.  相似文献   

18.
In this study, the bioremediation potentials of two seaweeds (Sargassum hemiphyllum and S. henslowianum) against pollution in a coastal mariculture area of Shenzhen, South China, were investigated by comparing the growth, nutrient bioaccumulation capacity of plants from the seaweed bed (control site) with plants from the fish farm. Results indicated that both species are potential candidates for bioremediation in the fish farm areas in terms of their high growth rates and high bioaccumulation capacities on inorganic nutrients. Both Sargassum spp. contain high levels of crude protein (11.7–14.0%) and crude fat (2.2–2.7%), suggesting high nutritional values. The S. hemiphyllum may serve as a good aquaculture fodder with high nutritional compositions and low heavy metal contents. However, heavy metals (Cr, Pb and Cd) of S. henslowianum exceed the maximum allowable concentrations as aquatic feed, which restricts its fodder application. In general, the results of this study may contribute to the marine pollution bioremediation in the coastal areas of South China, especially in mariculture zones.  相似文献   

19.
Concentrations of total hydrocarbons within the boiling point range of the alkanes n-C14 and n-C32 were determined in oysters, Pinctada margaratifera, from coastal waters of Kuwait. Levels of petroleum-derived hydrocarbons were highest in an area adjacent to the major oil loading facilities. Whether the use of dispersants to treat minor spills increases levels of incorporation of petroleum compounds into the food webs could not be concluded from the data of this study. Levels of total petroleum-type hydrocarbons in the oysters at this site were equivalent to those in mussels, Mytilus sp., from harbours, bays and urban coastal areas of California. The Kuwaiti oysters lacked a C28 pentacyclic triterpane that was present in extracts of mussels from southern California that had been recently exposed to a minor spill or to a natural seepage. Levels of DDE and PCB were comparable to those in relatively unpolluted areas of North America.  相似文献   

20.
Quantative population data for shallow Antarctic soft-bottom communities in King Edward Cove, South Georgia indicate that although once grossly polluted by organic effluent and fuel oil from a whaling station, the fauna recovered within some eight years after contamination ceased. The results are discussed in relation to comparable studies in other polar and temperate areas.  相似文献   

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