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261.
Peracarid crustaceans inhabit many marine benthic habitats and are good indicators of environmental conditions. There is,
however, a lack of information about diversity and distribution of peracarid crustaceans on the shallow subtidal sediments
of the Galician rias. In the summer of 1997, 27 subtidal stations were sampled in the Ría de Aldán, a ria on the southern
margin of the mouth of the Ría de Pontevedra (Galicia, NW Spain). A total of 16,191 peracarid individuals were collected,
comprising 125 species belonging to five orders. Amphipods were dominant in number of species and individuals, followed by
isopods and cumaceans. Multivariate analyses of these data indicated that depth and sediment granulometry were major determinants
of distribution and composition of peracarid assemblages in the ria. 相似文献
262.
Quantitative analysis of macrobenthic soft-bottom assemblages in South Shetland waters (Antarctica) 总被引:4,自引:3,他引:1
J.I. Sáiz-Salinas A. Ramos F.J. García J.S. Troncoso G. San Martin C. Sanz C. Palacin 《Polar Biology》1997,17(4):393-400
Macrobenthic assemblages were investigated at 26 stations located around Livingston Island, Deception Island and the Bransfield
Strait at depths ranging from 42 to 671 m. Representatives of 30 major taxa were found. The maximal density was 5,260 specimens·m−2 at Livingston Island; the mean abundance per station ranged from 160 to 4,380 specimens·m−2. The total biomass of the macrozoobenthos declined with depth, with mean values of 3,201 g·m−2 at shallower depths (< 100 m) and 210 g·m−2 further down (> 100 m). After multivariate analysis (cluster analysis, MDS) based on Bray-Curtis dissimilarities, most stations
could be assigned to one of three groups on the basis of distinct biomass differences between sites. The first cluster with
a rich Ascidiacea biomass is common on shallower bottoms. The second, with Ophiuroidea as a characteristic group, is common
on deeper bottoms. The absence of an ‘indicator’ taxon is characteristic of the remaining cluster of those stations with the
lowest biomass values. No significant correlations were detected between macrobenthic biomass and any sediment parameters
measured, probably because part of the benthos (i.e. the epifauna) could be better explained by the coupling with a highly
productive water column. The role of the epi-infauna sensu Gallardo as the main factor structuring benthic assemblages in
the investigated area is discussed.
Received: 7 March 1996/Accepted: 26 July 1996 相似文献
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瑞典国家财产委员会拥有骑士岛的所有权与管理权,并计划对该岛上所有的公共空间进行更新和开发,以提高其可达性与吸引力。该项目的核心是找到一种更新和修复岛屿的方法,从而在尊重历史价值的同时满足现代功能需求。对骑士岛南部的改造是岛上公共空间更新的第一部分。设计的关键条件是沿滨水区域创造可以供人步行与停坐的大面积空间,并在保持开放海港氛围的同时,对旧的道路铺装进行管理。设计者设计了一套灵活使用公共空间的综合解决方案,将开放空间与之前的码头一样,沿着水滨的形态进行布局。 相似文献
266.