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1.
The behaviour and oxygen consumption rates of adult mud snails, exposed to five metals individually (arsenic, cadmium, copper, silver and zinc) and to one combination of two metals (cadmium and copper), have been examined. The oxygen uptake of distressed and retracted snails was found to be lower than that of controls after exposure to all individual metals except cadmium, which resulted in an elevation of oxygen consumption. The combination of copper and cadmium resulted in a lower rate than either metal alone. 相似文献
2.
Maria Elizabeth Martin Arcos Breanyn Tiel MacInnes Patricia Arreaga Frances Rivera-Hernandez Robert Weiss Patrick Lynett 《Quaternary Research》2013
Tsunamis and storms instigate sedimentological and geomorphological changes to the coastal system, both long-term and ephemeral. To accurately predict future coastal hazards, one must identify the records that are generated by the processes associated with these hazards and recognize what will be preserved. Using eyewitness accounts, photographs, and sedimentology, this study documents pre- and post-tsunami conditions and constrains the timing and process of depositional events during and following the 11 March 2011 Tohoku tsunami in the coastal system at El Garrapatero, Galapagos Islands. While the tsunami acted as both an erosional and depositional agent, the thick, fan-like sand sheet in El Garrapatero was primarily emplaced by overwash deposition during high tide from swell waves occurring between 19–25 March and 17–22 April 2011. The swell waves were only able to access the terrestrial coastal system via a channel carved by the 2011 Tohoku tsunami through the barrier sand dune. This combined deposit could result in an overestimation of the hazard if interpreted to be the result of only one event (either tsunami or wind-generated waves). An analogous sand layer, younger than 1390–1530 cal yr BP, may record a similar, prior event. 相似文献
3.
This paper presents a method for the determination of array-element locations that makes no assumptions on the distribution of the sensors along the array or the array shape, and in fact, can be applied to the determination of the locations of sets of arbitrarily distributed sensors and arrays containing loops. The method employed uses multiple far-field sources. 相似文献
4.
John R MacInnes 《Marine environmental research》1981,4(3):217-227
The response of embryos of the American oyster, Crassostrea virginica, to various combinations of two or three metals (copper, mercury and zinc as the nitrates and chlorides) was studied in the laboratory at the optimal temperature and salinity regime for their development. The experimental design was a 3 × 3 × 3 factorial experiment using copper concentrations of 0,8 and 16 ppb; zinc concentrations of 0, 100 and 200 ppb and mercury concentrations of 0, 6 and 10 ppb. Highly significant toxic synergism was observed in the copper-zinc mixtures and three-metal mixtures of both salts, particularly at high concentrations. Although the chloride salt appeared to be slightly more toxic than the nitrate salt, the overall difference was not significant. 相似文献
5.
The least-squares estimate for the joint estimation of M directions-of-arrival in an array-processing scenario is rederived in a way that makes explicit use of the discrete Fourier transform. It is shown that the M-dimensional search algorithm can be made orders of magnitude faster than the traditional search algorithm. This new approach is compared via simulation with conventional narrowband beamforming. 相似文献
6.
A. Calabrese J.R. MacInnes D.A. Nelson R.A. Greig P.P. Yevich 《Marine environmental research》1984,11(4):253-274
The purpose of this study was to determine the long-term accumulation of either silver or copper from low concentrations in seawater by blue mussels, Mytilus edulis. Mussels raised from eggs in the laboratory to the age of 2·5 months (approximately 4·5 mm in length) were continuously exposed to 0, 1, 5 and 10μg/liter of either silver (nitrate) or copper (chloride) and sampled at 12, 18 and 21 months for growth studies, measurements of metal accumulation and histopathological examination.Whole-body soft tissues were analyzed for the presence of both silver and copper, as background levels of copper in the incoming seawater averaged 2–4 μg/liter. Mussels exposed to silver had accumulated significant amounts of silver only at the highest test concentration (10 μg/liter Ag) after 12 months, but at 18 and 21 months significant levels were accumulated at all three test concentrations. Mussels exposed to copper accumulated significant amounts of copper at 5 and 10 μg/liter Cu after all three sampling periods, but not at 1μg/liter. Silver-exposed animals also accumulated significantly greater amounts of copper than control animals.In a comparative study, field-collected juvenile mussels (approximately 16·1 mm in shell length) and adult mussels (approximately 53·4 mm in shell length) were exposed for 12 months to 0, 5, 25 and 50 μg/liter silver only and subsequently sampled for metal-accumulation analyses and growth measurements. Juvenile mussels accumulated significant amounts of silver at all test concentrations, with the exception of mussels exposed to 5 μg/liter Ag for 6 months. Copper accumulation in the silver-exposed juveniles was significant only at 50 μg/liter Ag after 6 months, but at all test concentrations after 12 months. Adult mussels exposed to silver accumulated significant levels of both silver and copper, but at somewhat lower levels than juveniles.In the growth study, silver had no effect on laboratory reared mussels at the highest concentration of 10 μg/liter tested, whereas copper at 10 μg/liter did appear to affect growth as early as 4 months after the start of experimental exposure. Field-collected juvenile mussels did show inhibition in growth after 6 months' exposure to 25 and 50 μg/liter Ag, with some growth occurring after 12 months. Adults also showed inhibition in growth after 6 months but not at 12 months.Histopathological examination of mussels exposed to either 5 or 10 μg/liter of copper for 18 months showed changes in the digestive diverticula, gastrointestinal tract, reproductive tract and muscle tissues. These changes were more noticeable in mussels exposed to 5 μg/liter Cu than in those exposed to 10 μg/liter. Mussels exposed to silver for 21 months showed yellowish to black particulate deposition in the basement membrane and connective tissue of the various organs and tissues. Silver deposition increased with increasing test concentration. 相似文献
7.
P. A. W. Robertson J. MacInnes O. A. E. Sparagano I. Purdom Y. Li D. H. Yu Z. J. Du H. S. Xu B. Austin 《中国海洋大学学报(英文版)》2002,1(2):153-156
Pollution has a considerable effect on biological communities, in terms of size and diversity of the populations. Yet, the
precise consequences of human activity on microbial communities in the marine environment are poorly understood. Therefore,
in an ongoing collaborative research programme between Heriot-Watt University and the Ocean University of Qingdao, bacteria
were isolated in 1999 and 2000 from marine sediment, seawater, seaweed, fish and shellfish, taken from locations in Shandong
Province adjacent to Qingdao. Sampling locations were comprised of industrial and aquacultural sites and a clean, control
site. In order to analyse microbial diversity, a polyphasic approach was adopted for characterisation of these isolates, specifically
through examination of key phenotypic traits, i.e. using Biolog GN MicroPlate™ profiles, bacterial whole cell protein profiles and 16S and 23S rRNA gene sequences. These techniques yielded complex taxonomic
data, which were subjected to statistical and cluster analyses. The application of these methods to studies of microbial communities
is discussed. 相似文献
8.
Aerobic, heterotrophic bacteria, recovered from two sites located on the west coast of Scotland, were compared to cultures
obtained in a similar way from industrial, aquacultural and clean sites in the vicinity of Qingdao, Shandong, P. R. China.
Gram-negative bacterial cultures were examined by BIOLOG-GN, and the data analysed by the simple matching (SSM) and Jaccard coefficients (SJ) and unweighted average linkage clustering using NTSys. The output revealed that 20% of the bacteria, namely, Acinetobacter johnsonii, Aquaspirillum dispar, Pseudomonas spp. (two groups), Sphingobacterium sp., Vibrio, sp., V. campbellii, V. mimicus and V. hollisae, were common between the two geographical locations. However, the study revealed shortcomings with the BIOLOG-GN system for
the study of coastal Gram-negative bacteria. 相似文献
9.