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141.
The wedge sole Dicologlossa cuneata (Moreau, 1881) is a coastal species that lives along the inner shelf waters of the Gulf of Cadiz down to a depth of 115 m. Its fishery, the size composition of the exploited population, and its reproduction have been studied on the basis of data acquired from commercial statistics from 1984 to 1994 and from sampling carried out during 1993 and 1994. The relative abundance of the species and its geographic and bathymetric distribution have been examined by analysis of four trawl surveys carried out from 1992 to 1994. D. cuneata is captured mainly by the trawl fleet, and to a lesser extent by gillnet gears. Wedge sole fishery has a marked seasonality. Size-frequency distributions from commercial samples and from bottom-trawl surveys are very similar, ranging from 12 to 26 cm total body length (TL). D. cuneata is a “repeat-spawner”. Peak spawning is from January to May. Females attain sexual maturity at 18 cm TL, while sexually mature males have been observed at 15 cm TL. The flexibility of the spawning strategy of D. cuneata throughout its distribution range is discussed. The scarcity of small specimens in the monthly samples and sequential spawning throughout the year prevented the estimation of growth parameters by means of length-frequency analysis. D. cuneata is present in greatest abundances in the sandy–muddy bottoms of the Guadalquivir River mouth at 15 to 30 m depth. Its optimum habitat coincides with the principal commercial fishing grounds. The possibility of reproductive vertical migration is discussed, but more precise data are needed before a viable hypothesis can be made. Received: 1 July 1997 / Accepted: 27 November 1997  相似文献   
142.
Environmental Science and Pollution Research - Catalyst samples based on SiO2-supported TiO2 were prepared with the incorporation of Ag (metal), S (nonmetal), and ZnO@S (semiconductor and...  相似文献   
143.
Journal of Polymers and the Environment - PLA has aroused industrial and scientific interest in recent years, mainly due to its biodegradable character. However, PLA is brittle and displays low...  相似文献   
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