Effects of mining wastes on a seagrass ecosystem: metal accumulation and bioavailability, seagrass dynamics and associated community structure   总被引：1，自引：0，他引：1  

Marín-Guirao L  Atucha AM  Barba JL  López EM  Fernández AJ 《Marine environmental research》2005,60(3):317-337

Two different Cymodocea nodosa (Ucria) Ascherson beds growing in mining-contaminated sediments were compared with two reference beds in the Mar Menor coastal lagoon. The accumulation of Zn, Pb and Cd in different fractions of the plant, the sediment parameters that regulate the availability of metals, the seabed structure and dynamics of each seagrass bed and its associated macroinvertebrate community were studied. C. nodosa accumulates metals from the sediments and reflects their bioavailability for this seagrass. At each station, the metal content of the rhizomes was lower than that of leaves and roots. The concentration of acid-volatile sulfides does not seem to influence the availability of metals to the seagrass, possibly due to oxygen transport to underground tissues. The highest metal concentration in all the contaminated stations was found in the leaf-biofilm, due to the formation of complexes between metals and the extracellular polymeric substances that form the biofilm. All the seagrass beds were seen to be undergoing expansion, those growing in contaminated sediments accumulating great quantities of metals and showing highest photosynthetic leaf surface area and highest leaf biomass. However, these structural parameters were not seen to be responsible for the differences in the faunal composition observed between contaminated and reference beds. Moreover, the multivariate analysis identified the metal content of leaves, biofilm and sediments as important variables that may be responsible for these differences in faunal composition. In this study we have demonstrated that both the seagrass C. nodosa and the biofilm on the plant leaves may be used as environmental tools in the Mar Menor lagoon. The former is an useful indicator of sediment contamination, whereas the latter seems to be a good sentinel of water quality.  相似文献   

Aspects of demographic decentralization in some regions of Southern Italy     

Frallicciardi AM 《Rivista geografica italiana》1989,96(1):27-60

The author analyzes spatial mobility in continental Southern Italy in order to establish the extent of urban decentralization in the region. She concludes that such decentralization is occurring throughout the region, but in different forms and with different effects for individual locations. (SUMMARY IN ENG AND FRE)  相似文献   

Near-field dispersion of produced formation water (PFW) in the Adriatic Sea: an integrated numerical-chemical approach     

Cianelli D  Manfra L  Zambianchi E  Maggi C  Cappiello A  Famiglini G  Mannozzi M  Cicero AM 《Marine environmental research》2008,65(4):325-337

Produced formation waters (PFWs), a by-product of both oil and gas extraction, are separated from hydrocarbons onboard oil platforms and then discharged into the sea through submarine outfalls. The dispersion of PFWs into the environment may have a potential impact on marine ecosystems. We reproduce the initial PFW-seawater mixing process by means of the UM3 model applied to offshore natural gas platforms currently active in the Northern Adriatic Sea (Mediterranean Sea). Chemical analyses lead to the identification of a chemical tracer (diethylene glycol) which enables us to follow the fate of PFWs into receiving waters. The numerical simulations are realized in different seasonal conditions using both measured oceanographic data and tracer concentrations. The numerical results show the spatial and temporal plume development in different stratification and ambient current conditions. The analytical approach measures concentrations of the diethylene glycol at a maximum sampling distance of 25 m. The results show a good agreement between field observations and model predictions in the near-field area. The integration of numerical results with chemical analyses also provides new insight to plan and optimize PFW monitoring and discharge.  相似文献   

Beach morphodynamics forcements in oiled shorelines: Coupled physical and chemical processes during and after fuel burial     

Bernabeu AM  Nuez de la Fuente M  Rey D  Rubio B  Vilas F  Medina R  González ME 《Marine pollution bulletin》2006,52(10):1156-1168

In November 2002, the sinking of the Prestige oil tanker off the Galician coast (N.W. Spain) caused the largest ecological catastrophe in the history of Spain, affecting the coast called the 'Costa da Morte' (Galicia, N.W. Spain). This work is focused on the study of the oil contamination of the intertidal area of two beaches located on this stretch of coast. The study of twenty cores extracted from both beaches has identified fuel embedded in the sedimentary column up to a depth of 2.38 m (this being the maximum depth of extraction). This, along with the presence of oil below the groundwater indicates the existence of a new factor which determines the burial of oil: the morphodynamic behaviour of the beach. Furthermore, this morphodynamic variation conditions the physical appearance of the buried oil. Four different types have been identified: tar-balls (cm), particles (mm), oil coatings on sediment grains and on emulsion, with distribution patterns conditioned by the degree of wave exposure. The analysis of the information obtained have permitted the development of a conceptual model of the burial and oil evolution in the sedimentary column in relation to wave exposure, and thus to the morphodynamic variability of the beach.  相似文献   

Trace metals and organic compounds in the benthic environment of a subtropical embayment (Ubatuba Bay, Brazil)     

Muniz P  Pires-Vanin AM  Martins CC  Montone RC  Bícego MC 《Marine pollution bulletin》2006,52(9):1098-1105

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PCBs and PAHs in sea-surface microlayer and sub-surface water samples of the Venice Lagoon (Italy)   总被引：1，自引：0，他引：1  

Manodori L  Gambaro A  Piazza R  Ferrari S  Stortini AM  Moret I  Capodaglio G 《Marine pollution bulletin》2006,52(2):184-192

Polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) are two classes of micropollutants intensively monitored and regulated due to their toxicity, persistency and wide diffusion. Their concentrations have been investigated in sea-microlayer (SML) and sub-surface water (SSW) samples collected at two sites of the Venice Lagoon, a fragile ecosystem highly influenced by industrial and anthropogenic emissions. The total sigmaPCB concentration varies from 0.45 ng/l to 2.1 ng/l in SSW while a clear enrichment is observed in the SML, where it ranges from 1.2 ng/l to 10.5 ng/l. The total sigmaPAH concentration shows marked differences between the two stations and varies from 12.4 ng/l to 266.8 ng/l in SSW; in SML it is more uniform and ranges from 19.6 ng/l to 178.9 ng/l. The enrichment factors are not larger than 1 for both pollutants in the 'dissolved' phase, while they are most significant for the 'particulate' phase (sigmaPCB: 5-9; sigmaPAH: 4-14).  相似文献   

The Humber Estuary, Eastern England: Strategic planning of flood defences and habitats     

Edwards AM  Winn PS 《Marine pollution bulletin》2006,53(1-4):165-174

The Humber Estuary Shoreline Management Plan provides a long-term strategy for investment in sustainable defences to reduce the risk to people and property from flooding in part of Eastern England. In addition to the estuary's economic importance with its ports, industry and the third of a million people living on its floodplain, the Humber is of outstanding value for wildlife and its historic environment. The plan has to meet the needs of these activities and take account of rising sea level. It is based on extensive technical studies and modelling. The realignment of some embankments is being examined so that the creation of intertidal habitat will offset losses from coastal squeeze, increase the stability for some lengths of embankment and reduce extreme high flood levels in the tidal rivers. The 80 ha Paull Holme Strays managed realignment wetland was completed in the summer of 2003 and work is in progress on another at Alkborough. Other such realignment will be developed as part of the implementation of the long term strategy.  相似文献   

Environmental pollution and natural populations: a biomarkers case study from the Iberian Atlantic coast     

Quintaneiro C  Monteiro M  Pastorinho R  Soares AM  Nogueira AJ  Morgado F  Guilhermino L 《Marine pollution bulletin》2006,52(11):1406-1413

The degradation of estuaries is a result of human activities which overloads the environment with substances of both industrial and/or natural origins. Bioindicators have been consistently used to interpret effects of contaminants in the environment. In this study, the use of biomarkers (particular measurable characteristics of a bioindicator organism) was used to evaluate the contamination by xenobiotics of Crangon crangon natural populations. The central aim was to evaluate the capability of a battery of biomarkers to discriminate sites with different types of contamination. The activity of the enzymes cholinesterases (ChE), lactate dehydrogenase (LDH) and glutathione S-transferases (GST) were used as biomarkers. In addition, the ChE form(s) present in the cephalotorax of C. crangon were characterised. Organisms were seasonally sampled from winter 2001/2002 to autumn of 2002, at "reference" sites and at sites that receive agricultural, industrial and/or urban effluents. Results obtained in the characterisation of ChE with different substrates and selective inhibitors demonstrate that the form of ChE present in the cephalotorax of C. crangon shows proprieties of vertebrates' AChE and therefore it may be classified as true AChE-like ChE. The battery of biomarkers exhibited seasonal and local variations, apparently related to agricultural, industrial or urban effluent contamination. The tested biomarkers proved to be able to discriminate sources of environmental contamination, and confirms C. crangon as a sensitive species suitable to be used as a bioindicator.  相似文献   

分析预测同心支撑钢结构系统的地震性能     

Reme.  AM 范淑杰 《世界地震工程》1998,14(3):68-78

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小兴安金矿成因     

日.  AM 屈世远 《黑龙江地质情报》1999,(2):15-25

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