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1.
On 3 December 1987, the supply ship Nella Dan ran aground at Macquarie Island (54°29′S, 158°58′E) releasing about 270 000 I of oil, mostly light marine diesel, into the sea. At the time of the incident, many marine invertebrates were washed up dead along 2 km of shoreline. Twelve months later, the shore community was investigated using 1. algal and invertebrate populations of the littoral and sublittoral rocky shore, and 2. the invertebrate communities living in the holdfasts of the giant kelp Durvillaea antarctica, which were collected for later examination. Investigations were undertaken at both affected and control locations. Analyses of differences in community structure involved nested ANOVA and multidimensional scaling techniques. On the rocky substrate, the effect of the spill was restricted to some biota of the lower littoral and sublittoral zones—particularly echinoderms and the patellid limpet Nacella macquariensis. There were differences in cover for some algal species between locations. Within the kelp holdfasts, communities were dominated by peracarid crustaceans at control locations and by polychaetes (particularly the opportunistic groups—capitellids, cirratulids and spionids) at oil-affected locations.
The communities have recently been re-surveyed (in the summer of 1994–1995) to assist in the interpretation of the results and to gauge the extent of recovery of the affected biota. 相似文献
2.
Lado-Insua Tania Pérez MontseDiz Angel P. Presa Pablo 《Continental Shelf Research》2011,31(5):466-475
The sinking of the tanker Prestige in November 2002 off the coast of Galicia resulted in the release of about 60,000 tons of heavy oil. The oil-spill provoked a serious environmental impact in Spanish and French coasts, which biological consequences are still being assessed. In this study we address the temporal dynamics of genetic diversity in some mussel populations impacted by the oil-spill. Changes in genetic diversity can be measured in natural populations provided that serial samples are available from before (year 2000) and after (years 2003, 2005) the oil-spill. Analyses of seven microsatellites indicate a weak but significant increase of genetic variation after the spill. This phenomenon is interpreted herein in terms of a balance between a enhanced genome mutability on microsatellite variation and a low genetic drift due to toxicants and asphyxia although other stochastic phenomena cannot be ruled out. Per locus annotation showed that in spite of the allelic changes observed in the period 2000-2005, the final size of most allelic series remained quite alike to those of year 2000. Present genetic data suggest that the genotoxic impact of the Prestige spill did not compromise the genetic diversity of studied mussel populations, at least regarding the genetic markers analysed. 相似文献
3.
Zvuloni A Mokady O Al-Zibdah M Bernardi G Gaines SD Abelson A 《Marine pollution bulletin》2008,56(3):430-438
Coastal marine reserves in general, and coral reef reserves in particular, are typically composed of scattered patches separated by uninhabited areas. Due to the sessile mode of life of adult corals, larval connectivity is often the only agent of gene flow between reef localities. In this study we examined the connectivity between populations of the common scleratinian coral Stylophora pistillata at the northern tip of the Gulf of Aqaba (Red Sea), using the rDNA ITS (internal transcribed spacer) as a molecular marker. Sequence comparisons among recruits indicated very similar, equally-diverse, assemblages of recruits in both the northern (highly affected by anthropogenic disturbances) and southern (less affected) study sites, implying a high larval connectivity or common sources of larval supply. By contrast, sequence diversity observed among adults declined sharply from southern to northern sites, accompanied by genetic differentiation of the respective populations. Based on Fu's Fs-test of selective neutrality, it may be suggested that various post-settlement selective regimes, presumably more intense in the northern sites, provide a reasonable explanation for the observed patterns of genetic diversity. The suggested hypothesis is supported by the sharper decline in sequence diversity found between recruits and adults in the northern sites. This study exemplifies the necessity to consider local selective factors, in addition to larval connectivity, when managing marine reserves. 相似文献
4.
Following the oil spill from the Russian tanker Nakhodka in 1997 in the Sea of Japan, polycyclic aromatic hydrocarbons (PAH) were monitored for three years in some molluscs from the Mikuni-cho shore in Japan. Total PAH concentrations in marine organisms except for spiny top shell, ranged from 5.3 to 32.7 ng/g wet weight, but no trends were evident. Total PAH concentration in spiny top shell (Turbo cornutus) was 44 ng/g w.w. in the first month after the oil spill. However, it rapidly decreased to less than 5.4 ng/g w.w. from the second month. Spiny top shell, which was exposed to dietary Nakhodka heavy fuel oil, concentrated benzo(a)pyrene to 17.1 ng/g w.w. after two weeks of exposure and then rapidly eliminated it during an elimination phase. These results suggest that spiny top shell accumulates PAHs because of their low ability to metabolize PAH, but it can excrete parent PAHs rapidly when removed from the source of contamination. Thus it is suitable as an indicator organism in monitoring oil contamination. It can also be inferred from these field and laboratory investigations that, in three years, organisms from the Mikuni-cho shore seem to have adequately recovered from the Nakhodka oil spill contamination. 相似文献
5.
Teruhisa K Masahiro N Hiroshi K Tomoko Y Kouichi O;Marine Life Research Group of Takeno 《Marine pollution bulletin》2003,47(1-6):99-104
A major heavy-oil spill from the Russian tanker Nakhodka occurred in the Sea of Japan on 2 January 1997. We investigated the impacts of this spill on a rocky intertidal ecosystem along the southern coast of the Sea of Japan. We selected Imago-Ura Cove as our study site to observe temporal changes along the oiled shore, because minimal cleaning effort was made in this area. Field surveys were conducted every autumn and spring from 1997 to 2000. We measured coverage by macroalgae in 1 x 1-m(2) quadrats and counted the animals in 5 x 5-m(2) quadrats along the intertidal zone. Changes in the ecosystem caused by the oil spill were analyzed by applying a geographical information system (GIS) to the Sea of Japan for the first time. The GIS showed that following the accident there were heavily oiled areas in sheltered regions, but these decreased over the three years. It also showed that coverage by macroalgae and the number of animals increased, although some species of algae with microscopic sporophyte generations, and some populations of perennial shellfish, remained stable or decreased during the study period. GIS was able to trace temporal changes in intertidal communities resulting from the impacts of heavy oil on flora and fauna at a spatial scale of 10-100 m. GIS is thus a practical tool for visualizing, analyzing, and monitoring changes in an ecosystem polluted by oil, taking into account topographic differences along the coastline. 相似文献
6.
Several coastal rocky shores in the northern Chile have been affected by the discharges of copper mine tailings. In spite of this, the temporal and spatial variation on the diversity and composition of their intertidal benthic communities has scarcely been studied. The objectives of the present study were to analyse and to compare quantitatively the temporal variation on the diversity, cover and composition of sessile species in rocky intertidal benthic communities of the northern Chilean coast, in relation to the presence of copper mine tailings. The results show that the drastic reduction on the sessile species diversity and the monopolization of the substrate exerted by the green algae Enteromorpha compressa, are common and permanent features of the intertidal rocky shores affected by copper mine tailings. Such spatial (between sites) and temporal (seasonal) variation of these changes has been associated with the relative concentrations of trace metals and inorganic particles of the mining wastes. Our results suggest that the mechanical effects of resuspended and settling tailings are a more likely cause. 相似文献
7.
Edgar GJ Kerrison L Shepherd SA Veronica Toral-Granda M 《Marine pollution bulletin》2003,47(7-8):276-283
Densities of fishes, invertebrates and plants at rocky intertidal and shallow subtidal sites were censused 1-2 days prior to the Jessica oil spill and compared with information obtained for the same sites one month after the spill, both for sites impacted by oil and unaffected reference sites. While the availability of pre-spill data made this analysis one of the most powerful to date for testing impacts of oil on shoreline environments, no clear changes attributable to oiling could be identified. Discharged oil appeared to cause very little impact in the intertidal and shallow subtidal zones, with such impacts lying within the range of natural spatial and temporal variation at sites investigated. Factors considered to minimize impact in Galápagos included paucity of fully sheltered shores in spill path, moderate wave action, warm temperature, high levels of sunlight, and mixing of bunker oil with diesel. 相似文献
8.
Preliminary study on responses of marine nematode community to crude oil contamination in intertidal zone of Bathing Beach, Dalian 总被引：1，自引：0，他引：1
This study investigated the responses of marine nematodes to crude oil contamination in polluted and relatively uncontaminated sites in Dalian Xingang, China, 40 days after an oil spill. Samples were taken at different tide levels on the beach and at different positions along the beach. We present the results of a comparison of nematode assemblages from undisturbed sediment from the Xiajiahezi Bathing Beach with those from sediment from the Xinghai Bathing Beach contaminated with crude oil. A total of 1666 nematodes from 26 genera were found in this study. Results showed significant differences in nematode assemblages between samples from undisturbed controls and those from the polluted area. Nematode abundance, number of species, diversity and species richness decreased significantly with increasing levels of crude oil contamination. Fifteen genera were eliminated and seemed to be composed of species intolerant to crude oil contamination; only the abundance of Marylynnia sp. increased slightly. 相似文献
9.
Changes in genetic variability and allele frequency can be responses from natural populations when encountering a novel contaminated environment. The genetic diversity and population structuring of natural populations of the gastropod Littorina brevicula from heavy-metal polluted and unpolluted environments along the southeast coast of Korea were examined using two mtDNA markers, cyt b and ND6. This study applied a nested clade analysis to test the existence of structuring association of haplotype distribution with environments (polluted and unpolluted). No genetic differences within cyt b mtDNA were detected between environments. On the other hand, differences in population haplotype diversity and structuring were found within ND6 mtDNA between polluted and unpolluted environments. The ND6-mtDNA haplotype (=genetic) diversity was significant lower in polluted environments. This decreased genetic diversity along with differences in the haplotype distribution within heavy-metal polluted environments compared to those unpolluted ones stand out as emergent effects from pollution at a population level. In this study, we propose the use of different approaches, such as the NCA, that takes into account the rare haplotypes, when assessing the effects of pollution on population genetic structuring. 相似文献
10.
Invasions are common in coastal marine environments where proximity to urban areas should influence the number of non-native organisms due to the likelihood of unintentional introductions from urban centers. Invasive species are widely recognised as important agents of global change, and can colonize new habitats and even cause local extinction of native species. This study was focused on the invasive marine macroalga Sargassum muticum, a problematic invasive species on the West coast of America and in European waters. An intensive survey was carried out along the Galician coast (North West of Spain) from March to August 2008 to determine the current distribution of this species, and its relationship with level of urbanization and native macroalgal diversity. We sampled the presence of S. muticum and native macroalgae in the mid and low intertidal zones of twenty rocky shores distributed along ten rias. Rias were grouped into high and scarcely urbanized based on their population density. Results indicated that S. muticum was present in nine out of the ten rias, confirming its presence in most of the intertidal rocky shores of Galicia twenty years after it was first observed. The presence of S. muticum was not related to the degree of urbanization of the rias, and its distribution and abundance did not seem to be influenced by diversity or functional groups of native algae. In addition, there was a great variability in the percentage cover, number and length of individuals amongst localities and rias suggesting that both large-scale and local processes may play a role in the distribution of this species. This study highlights the importance of future research into the distribution and impact of introduced algae and proves the urgent need for monitoring programmes and increasing efforts to prevent and control new introductions. 相似文献
11.
The vernal pool fairy shrimp (Branchinecta lynchi) (Eng et al. in J Crustac Biol 10:247–277, 1990) is broadly distributed throughout California’s Central Valley with disjunct populations in southern California and southern
Oregon. A survey of genetic variation at the mitochondrial cytochrome c oxidase subunit I (COI) gene was conducted from individuals
collected throughout the range of the species. Phylogenetic analysis of unique haplotypes could not resolve any significant
genetic partitions below the species level. A detailed analysis of samples from two pools indicates that sample sizes underestimate
overall variation, but that the general phylogeographic pattern still holds. Evidence was found for a putative long-distance
dispersal event between Central Valley sites and the Oregon site. These results indicate that geographically limiting stochastic
colonization followed by local diversification may be important in governing current genetic structure for this species. Future
and current conservation/restoration efforts should recognize the geographic limitations to population structure for this
species and focus on local endemic genetic variation. 相似文献
12.
In order to ensure conservation of mangroves, genetic diversity in remaining populations must be explored. Both morphological and isozyme analyses were used and compared in investigating the intra- and inter-estuarine variation in Avicennia marina in Sydney, the most urbanised area in Australia. Sediment characteristics, metal levels, tree attributes, leaf morphology and isozyme/allozyme analyses were conducted. Tree characteristics did not prove to be adequate genetic markers, but leaf morphology may be of use in this species. Isozyme/allozyme analyses indicated that genetic distance corresponded with geographic distance, although habitat metal levels may indicate local selection pressures. High levels of heterozygote deficiencies were displayed in each estuary, which could threaten future viability. The results hold implications for management as periodic isozyme analysis may be useful in indicating management needs. The identification of metal-tolerant types may also be useful. Transplantation among estuaries may assist in increasing genetic diversity, if considered desirable. Whatever the management aims, isozyme/allozyme analyses are shown to be useful for revealing genetic diversity in this species. 相似文献
13.
Valerio Ketmaier 《Aquatic Sciences - Research Across Boundaries》2002,64(1):66-75
Fifteen populations belonging to the Proasellus coxalis-group were surveyed for genetic variation at 19 enzymatic loci in order to clarify the degree of genetic structuring of this species at the scale of Central Italy. With Neighbour-Joining analysis, it was possible to identify two main clusters, the first grouping populations sampled in coastal areas of Central Italy, the second comprising several populations from inland areas of the Apennines. In the first group, genetic relationships follow a geographic scheme, with populations arranged according to the proximity of the collecting sites. The inland populations have less clear geographic relationships and a higher degree of genetic differentiation. In view of the paleogeography of the study areas, I hypothesise a more recent penetration of this taxon into the Central Italian alluvial coastal plains (subjected to cyclical marine ingressions during the Quaternary) from sources of colonisation in the inland areas. The higher genetic differentiation of the inland populations presumably reflects a longer evolutionary history and could be explained by the periodic fragmentation of river catchments during Pleistocene climatic fluctuations. Such an evolutionary scenario is supported by F-statistics analyses. Effective dispersal of individuals between populations can be hypothesised for the coastal populations but not for the inland ones. On the whole, there is a pattern of isolation by distance, but a large amount of gene flow seems to reflect historical rather than ongoing gene exchange. 相似文献
14.
Cyanobacterial mats are found at various locations along the coast of the Eastern Province of Saudi Arabia. Those mats were affected by severe oil pollution following 1991 oil spill. In this study, samples from Abu Ali Island were collected at three selected sampling sites across the intertidal zone (Lower, Middle, and Upper) in order to understand the effect of extreme environmental conditions of high salinity, temperature and desiccation on distribution of cyanobacteria along the oil polluted intertidal zone. Our investigation of composition of cyanobacteria and diatoms was carried out using light microscopy, and Denaturant Gradient Gel Electrophoresis (DGGE) technique. Light microscopy identification revealed dominant cyanobacteria to be affiliated with genera Phormidium, Microcoleus, and Schizothrix, and to a lesser extent with Oscillatoria, Halothece, and various diatom species. The analysis of DGGE of PCR-amplified 16S rRNA fragments showed that the diversity of cyanobacteria decreases as we proceed from the lower to the upper intertidal zone. Accordingly, the tidal regime, salinity, elevated ambient air temperature, and desiccation periods have a great influence on the distribution of cyanobacterial community in the oil polluted intertidal zone of Abu Ali Island. 相似文献
15.
The oil content in the sediment and the marine life along the arctic shores of Van Mijenfjord, Spitzbergen, were investigated about two years after a spill from diesel storage tanks. High values of oil were recorded in the sediment along the shore near the tanks. The shore fauna is generally poor in these areas and the only biological effect detected was the disappearance of the amphipod Gammarus setosus from the surface layers. 相似文献
16.
Spilmont N Denis L Artigas LF Caloin F Courcot L Créach A Desroy N Gevaert F Hacquebart P Hubas C Janquin MA Lemoine Y Luczak C Migné A Rauch M Davoult D 《Marine pollution bulletin》2009,58(1):55-476
From 1999 to 2005, studies carried out in the frame of regional and national French programs aimed to determine whether the Phaeocystisglobosa bloom affected the intertidal benthic communities of the French coast of the eastern English Channel in terms of composition and/or functioning. Study sites were chosen to cover most of the typical shore types encountered on this coast (a rocky shore, an exposed sandy beach and a small estuary). Both the presence of active Phaeocystis cells and their degradation product (foam) did have a significant impact on the studied shores. The primary production and growth rates of the kelp Saccharina latissima decreased during the bloom because of a shortage of light and nutrient for the macroalgae. On sandy sediments, the benthic metabolism (community respiration and community primary production), as well as the nitrification rate, were enhanced during foam deposits, in relation with the presence of bacteria and active pelagic cells within the decaying colonies. In estuarine sediments, the most impressive impact was the formation of a crust at the sediment surface due to drying foam. This led to anoxic conditions in the surface sediment and resulted in a high mortality among the benthic community. Some organisms also tended to migrate upward and were then directly accessible to the higher trophic level represented by birds. Phaeocystis then created a shortcut in the estuarine trophic network. Most of these modifications lasted shortly and all the systems considered came back to their regular properties and activities a few weeks after the end of the bloom, except for the most impacted estuarine area. 相似文献
17.
Vlahogianni T Dassenakis M Scoullos MJ Valavanidis A 《Marine pollution bulletin》2007,54(9):1361-1371
Mussels are used as sentinel organisms and bioindicators to evaluate the toxic effects of chemical pollutants in marine organisms, especially heavy metals, representing an important tool for biomonitoring environmental pollution in coastal areas. Antioxidant defence enzymes play an important role in cellular antioxidant defence systems and protect from oxidative damage by reactive oxygen species (ROS). Indigenous mussels Mytilus galloprovincialis of the Saronikos Gulf of Greece were used for monitoring heavy metal pollution in three polluted sites in the area and in one unpolluted site. Seasonal variations of the activity of antioxidant defence enzymes, superoxide dismutase (SOD) and catalase (CAT), as well as lipid peroxidation (LP) were measured as biomarkers in a period of three years in relation to concentrations of trace metals in their gills and mantle and compared to mussels from an unpolluted sampling site. SOD activity increased at least 2 fold at the polluted sites when compared to the control site (the high activity was recorded in the spring time). CAT activity was increased 2-3 times at the polluted sites, with high activity in the winter and spring time, compared to the control site. LP concentration was twice higher at the polluted sites, following the same seasonal pattern. Trace metals contents in mussels collected at polluted sites were 3-4 fold higher compared to the control site and showed moderate variations along the months, with a winter maximum followed by a summer pre-spawning minimum matching the seasonal trends of temperature and salinity. Our results showed that metal pollution in the Elefsis Bay (the most polluted coastal area) causes relatively medium levels of oxidative stress in tissues of mussels due to cellular oxy-radical generation. This study, which is the first in the area, showed that seasonal variations of the activity of antioxidant defence enzymes and LP concentrations in mussels can be used as potential biomarkers of toxicity for long-term monitoring in marine coastal ecosystems. 相似文献
18.
John Terje Staveland 《Marine pollution bulletin》1979,10(9):255-258
One year after an accidental spill of approx. 2000 t of Iranian crude oil on the west coast of Norway, specimens of the gastropod Littorina littorea were collected from the oil polluted shore and allowed to spawn in the laboratory. Snails were also collected from an unpolluted reference site. The oil contamination seemed to have no detectable effects on fertilization. However, the hatching success of the veliger larvae was significally less in the ‘oil polluted’ population. Some highly abnormal eggs were also observed in this egg population. 相似文献
19.
The macrobenthic fauna of the Milford Haven Waterway was studied in detail following the 'Sea Empress' oil spill in 1996. Contamination patterns indicated heaviest contamination of sediments by oil to have occurred in the lower reaches of the waterway, although water borne hydrocarbons are likely to have penetrated throughout the Haven. Generally, the communities showed little impact of contamination by oil, although some changes were evident at the population level. A decline in the amphipod fauna was observed throughout the Haven, with the genera Ampelisca and Harpinia and the family Isaeidae particularly affected. This was accompanied by increases in both the diversity and abundance of polychaete populations as opportunist species took advantage of the decline of the amphipod fauna. However, within five years of the spill the amphipod fauna has shown clear signs of recovery. The use of the polychaete/amphipod ratio as an indicator of oil pollution is discussed. 相似文献
20.
基于COI基因序列的太湖新银鱼遗传多样性 总被引：3，自引：0，他引：3
利用线粒体细胞色素C氧化酶I(COI)分子标记分析长江中下游太湖新银鱼(Neosalanx taihuensis)8个地理种群132个样本的遗传多样性.该基因630 bp片段的碱基序列共检出8个核苷酸变异位点(变异率1.27%),其中局域性单倍型居多(75%),群体单倍型多样性较高(h=0.576±0.036),而核苷酸多样性较低(π=0.00112±0.00204).不同地理种群遗传多样性差异显著:有人工移植历史种群遗传多样性较高、隔离度较高的种群遗传多样性较低,但大部分的遗传变异来自于种群内(54.83%),反映出地理隔离和人为干扰对太湖新银鱼遗传格局影响显著.研究表明COI基因适于银鱼科鱼类物种鉴别和系统发育研究,同时可为同种种群间遗传关系分析提供一定的信息. 相似文献