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581.
Avellaneda PM Englehardt JD Olascoaga J Babcock EA Brand L Lirman D Rogge WF Solo-Gabriele H Tchobanoglous G 《Marine pollution bulletin》2011,62(10):2157-2169
A relative risk assessment of biosolids disposal alternatives for cruise ships is presented in this paper. The area of study encompasses islands and marine waters of the Caribbean Sea. The objective was to evaluate relative human health and ecological risks of (a) dewatering/incineration, (b) landing the solids for disposal, considering that in some countries land-disposed solids might be discharged in the near-shore environment untreated, and (c) deep ocean disposal. Input to the Bayesian assessment consisted of professional judgment based on available literature and modeling information, data on constituent concentrations in cruise ship biosolids, and simulations of constituent concentrations in Caribbean waters assuming ocean disposal. Results indicate that human health and ecological risks associated with land disposal and shallow ocean disposal are higher than those of the deep ocean disposal and incineration. For incineration, predicted ecological impacts were lower relative to deep ocean disposal before considering potential impacts of carbon emissions. 相似文献
582.
Hydrocarbon composition and distribution in a coastal region under influence of oil production in northeast Brazil 总被引:1,自引:0,他引:1
Wagener Ade L Carreira RS Hamacher C Scofield Ade L Farias CO Cordeiro LG Luz LG Baêta AP Kalas FA 《Marine pollution bulletin》2011,62(8):1877-1882
Waters and sediments from the Potiguar Basin (NE Brazilian coast) were investigated for the presence and nature of polycyclic aromatic hydrocarbons (PAH) and aliphatic hydrocarbons. The region receives treated produced waters through a submarine outfall system serving the industrial district. The total dispersed/dissolved concentrations in the water column ranged from 10-50 ng L−1 for ∑16PAH and 5-10 μg L−1 for total aliphatic hydrocarbons. In the sediments, hydrocarbon concentrations were low (0.5-10 ng g−1for ∑16PAH and 0.01-5.0 μg g−1 for total aliphatic hydrocarbons) and were consistent with the low organic carbon content of the local sandy sediments. These data indicate little and/or absence of anthropogenic influence on hydrocarbon distribution in water and sediment. Therefore, the measured values may be taken as background values for the region and can be used as future reference following new developments of the petroleum industry in the Potiguar Basin. 相似文献
583.
The distribution, abundance and chemical characteristics of plastic production pellets on beaches of the island of Malta have been determined. Pellets were observed at all locations visited and were generally most abundant (>1000 m−2 at the surface) on the backshores of beaches with a westerly aspect. Most pellets were disc-shaped or flattened cylinders and could be categorised as white, yellow, amber or brown. The polymeric matrix of all pellets analysed by infrared spectroscopy was polyethylene and the degree of yellowing or darkening was associated with an increase in the carbonyl index, hence extent of photo-oxidation or aging. Qualitatively, pellets are similar to those reported for other regions of the Mediterranean in surveys spanning three decades, suggesting that they are a general and persistent characteristic of the region. 相似文献
584.
Keogh SM Cournane S León Vintró L McGee EJ Mitchell PI 《Marine pollution bulletin》2011,62(4):696-700
Radiocarbon levels were recorded in Fucus vesiculosus samples collected on a monthly basis over a three-year period at a site on the east coast of Ireland. The resulting data was analysed using a numerical model which estimates the transit times from the Sellafield plant to the sampling location, and the mean availability time of 14C in seaweed. With the inclusion of a model parameter allowing for seasonal variability in uptake by the Fucus, good correlation was observed between the predicted and measured concentrations. Future temporal trends of 14C Fucus concentrations along the eastern Irish coastline were modelled with the application of three possible prospective discharge scenarios, predicting 14C Fucus concentrations to reduce to ambient background levels within 2.5-years of discharges being set to zero. Such projections may prove helpful in assessing the consequences of discharge management and policy making in the context of the OSPAR convention. 相似文献
585.
Anthropogenic organic contaminants in water, sediments and benthic organisms of the mangrove-fringed Segara Anakan Lagoon, Java, Indonesia 总被引:1,自引:0,他引:1
Dsikowitzky L Nordhaus I Jennerjahn TC Khrycheva P Sivatharshan Y Yuwono E Schwarzbauer J 《Marine pollution bulletin》2011,62(4):851-80
Segara Anakan, a mangrove-fringed coastal lagoon in Indonesia, has a high diversity of macrobenthic invertebrates and is increasingly affected by human activities. We found >50 organic contaminants in water, sediment and macrobenthic invertebrates from the lagoon most of which were polycyclic aromatic compounds (PACs). Composition of PACs pointed to petrogenic contamination in the eastern lagoon. PACs mainly consisted of alkylated PAHs, which are more abundant in crude oil than parent PAHs. Highest total PAC concentration in sediment was above reported toxicity thresholds for aquatic invertebrates. Other identified compounds derived from municipal sewage and also included novel contaminants like triphenylphosphine oxide. Numbers of stored contaminants varied between species which is probably related to differences in microhabitat and feeding mode. Most contaminants were detected in Telescopium telescopium and Polymesoda erosa. Our findings suggest that more attention should be paid to the risk potential of alkylated PAHs, which has hardly been addressed previously. 相似文献
586.
最近,在苏门答腊俯冲带展开了一系列相互关联的海上及陆地研究,重点针对印度尼西亚2004年和2005年的板块边界地震破裂。这项由英国(英国苏门答腊联盟)、印度尼西亚、美国、法国和德国的科学家联手开展的研究计划旨在对这一边缘的地壳结构进行成像,以分析沿走向和上倾方向地震破裂 相似文献
587.
Experimental study of friction dissipators for seismic protection of building structures 总被引:1,自引:1,他引:0
This paper presents the results from unidirectional shaking table tests of two reduced scale steel models of a building frame, with one and two floors, respectively. These frames incorporate friction dissipators at every floor. The inputs are sine-dwells and artificial and registered earthquakes. This study is part of a larger research project aiming to assess the seismic efficiency of friction dissipators by means of an integrated numerical and experimental approach. Inside this framework, the main objectives of these experiments are to: (i) collect a wide range of results to calibrate a numerical model derived within the project, (ii) clarify some of the most controversial issues about friction dissipators (including behavior for inputs containing pulses, capacity to reduce resonance peaks, introduction of high frequencies in the response, and self-generated eccentricities), (iii) better understand their dynamic behavior, (iv) provide insight on the feasibility and reliability of using simple friction dissipators for seismic protection of building structures and (v) characterize the hysteretic behavior of these devices. Most of these objectives are satisfactorily reached and relevant conclusions are stated. 相似文献
588.
Guðmundsdóttir LÓ Ho KK Lam JC Svavarsson J Leung KM 《Marine pollution bulletin》2011,63(5-12):500-507
Using the dogwhelk Nucella lapillus as a biomonitor, we evaluated the organotin contamination along the Icelandic coast over nearly two decades. In 2008, adult dogwhelks collected from 30 locations were examined for imposex status. In 2009, tissue concentrations of six organotin species in dogwhelks from 16 of the 30 locations were analysed using gas chromatography-mass spectrometry. Tributyltin was the most predominant residue ranging from 2.07 to 70.38 μg kg(-1) dw, while triphenyltin was also detected at concentrations up to 22.79 μg kg(-1) dw. Higher total organotin concentrations and imposex indices were observed at locations near large harbours (Reykjavík and Hafnarfj?reur). By comparing the current imposex results with those of previous surveys (1992-2003), we found that recovery was slow near the large harbours, but more apparent near the smaller harbours. We also observed a notable increase in imposex at several northwest sites implying incessant input of organotins. 相似文献
589.
The radionuclides (210)Po and (210)Pb were examined to trace the cycling of particulate organic carbon (POC) and particulate organic nitrogen (PON) in the Zhubi coral reef lagoon. The net export flux of POC to the open sea is 14 mg Cm(-2) d(-1). However, the net exchange of PON has not yet been observed. On average, the vertical export fluxes in the lagoon of POC and PON, as derived from (210)Po/(210)Pb disequilibria, are 43 mg Cm(-2) d(-1) and 13.8 mg Nm(-2) d(-1), respectively. The deficit of (210)Po relative to (210)Pb in particulate matter provides evidence for the degradation of particulate organic matter. According to the mass balance budgets, 310 mg Cm(-2) d(-1) and 121 mg Nm(-2) d(-1) were recycled into dissolved fractions. Based on a first-order kinetics model, the degradation rate constants of POC and PON are 0.28 and 0.30 m(-1), respectively. Thus, (210)Po and (210)Pb can quantify the cycling of carbon and nitrogen in this coral lagoon. 相似文献
590.
Senal MI Jacinto GS San Diego-McGlone ML Siringan F Zamora P Soria L Cardenas MB Villanoy C Cabrera O 《Marine pollution bulletin》2011,63(5-12):195-200
Submarine groundwater discharge (SGD) on the reef flat of Bolinao, Pangasinan (Philippines) was mapped using electrical resistivity, 222Rn, and nutrient concentration measurements. Nitrate levels as high as 126 μM, or 1-2 orders of magnitude higher than ambient concentrations, were measured in some areas of the reef flat. Nutrient fluxes were higher during the wet season (May-October) than the dry season (November-April). Dissolved inorganic nitrogen (DIN=NO3+NO2+NH4) and soluble reactive phosphorus (SRP) fluxes during the wet season were 4.4 and 0.2 mmoles m(-2) d(-1), respectively. With the increase population size and anthropogenic activities in Bolinao, an enhancement of SGD-derived nitrogen levels is likely. This could lead to eutrophic conditions in the otherwise oligotrophic waters surrounding the Santiago reef flat. 相似文献