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11.
The potential role of microbial consortia on sponge chemistry is well known. However, how environmental factors affect microbial and chemical profiles and how these shifts affect the sponge holobiont are far from being understood. This study experimentally investigated the effect of light on both the concentration of secondary metabolites and the bacterial assemblages of the sponge Aplysina aerophoba. We quantified major brominated alkaloids (BAs) using a high‐performance liquid chromatography system coupled with a UV‐detector and analysed sponge‐associated bacteria using denaturing gradient gel electrophoresis of 16S rRNA gene amplicons. We identified distinct chemical and bacterial profiles between the ectosome and the choanosome of A. aerophoba. The abundance of most secondary metabolites increased regardless of the illumination regime. We found that the probability of occurrence of three microbial phylotypes (operational taxonomic units 84, 86 and 87) was strongly associated with increasing concentrations of three brominated compounds (aerophobin‐1, aplysinamisin‐1 and isofistularin‐3). Although the role of these bacteria remains uninvestigated, these associations between natural products and specific microbial phylotypes outline further hypotheses that will improve our understanding of the organization and functioning of these complex host–symbiont interactions.  相似文献   
12.
13.
Henry M.  Reiswig 《Marine Ecology》1981,2(4):273-293
Abstract. The major in situ physiological activities of the common, tropical, West Atlantic demosponge Verongia (= Aplysina) fistularis were determined in order to relate the carbon and energy budgets of this species to the two contrasting patterns documented for bacteriosponges (sponges harbouring large symbiotic bacterial populations) and non-bacteriosponges (sponges lacking such large bacterial populations and considered "normal" sponges). Measurements of specimen dimensions and exhalant water velocity, and samples of exhalant water were obtained from undisturbed field specimens for estimation of rates of water transport, respiration and particulate organic carbon retention. Partial carbon and energy budgets were developed from calculated rates of particulate feeding, respiration and growth. The bacteriosponge, V. fistularis , is very similar to Verongula sp., another bacteriosponge, in terms of high respiration rate, 5.33% of available oxygen being removed during a single-pass water transit, and gross imbalance in particulate carbon and energy budgets, particulate sources supplying only 14% of respiration and growth requirements. The nutrient resource spectrum of Verongia fistularis and other bacteriosponges appears to be overwhelmingly dominated by dissolved organic matter, and thus contrasts strikingly with the present knowledge of nutrition in the normal non-bacteriosponges.  相似文献   
14.
Abstract. Bioeroding sponges are highly specialised to live in and to erode various natural and man-made calcareous substrates. They encounter very different substrate features. Previous field observations suggest that damage caused by sponge bioerosion may vary with substrate density and architecture. This study aims to experimentally investigate influences of structurally different calcareous substrates on bioerosion activities of Cliona orientalis Thiele, 1900 , an important eroder of inshore Great Barrier Reef calcium carbonate. Blocks were made of the corals Goniopora tenuidens , massive Porites sp., Astreopora listeri, Favites halicora, Favia pallida, Goniastrea retiformis and Cyphastrea serailia , and of the clam Tridacna squamosa . They were grafted with C. orientalis tissue and re-examined after 9 months. Block weight loss, increase of pore volume and differences in breaking stability were measured as indicators of sponge erosion.Erosion caused by C. orientalis differed between substrates and was significantly more pronounced in denser materials with lower pore volume and in coral blocks with more structural barriers. Coral substrates with imperforate thecae and thicker dissepiment walls were more strongly eroded than those with perforate thecae and thinner dissepiments. At similar growth rates, more material has to be removed in denser material with more barriers compared to more porous substrates. Existing pores will be occupied, resulting in lower erosion rates. Erosion capabilities of the sponge could best be detected by the blocks' loss in dry weight, but the sponges also significantly reduced block breaking stability. Change in pore volume was not found to be a reliable parameter to investigate sponge erosion.  相似文献   
15.
Low-Tide Exposure of Sponges in a Caribbean Mangrove Community   总被引:1,自引:0,他引:1  
K. Rützler 《Marine Ecology》1995,16(2):165-179
Abstract. Sponges on subtidal red-mangrove prop roots may become exposed to air many times per year during very low tides. Full exposure is stressful and potentially fatal, particularly if occurring in full sun. Large root sponges show distinct species zonation between mean low water and -0.5 m. Haliclona implexiformis and Lissodendoryx isodictyalis are near the top while Scopalina ruetzleri are near the lower end of the range. Temporary experimental desiccation resulted in 100% recovery of all three species after they had been exposed to either sun or shade for up to 2 h. Scopalina is the least resistant and lost over 90% tissue within 3 days after the 4-h and 6-h experiments; the remaining cell mass succumbed to infestation by microbes. Haliclona and Lissodendoryx recovered from as much as 6 h in full sun but lost 85% and 80% of the original tissue volume, respectively. In Lissodendoryx , clusters of larvae developed in the regenerating fragments. Water loss tolerated by the three species is estimated as 66% of wet weight in Haliclona , 54% in Lissodendoryx and 38% in Scopalina . Salinity of interstitial seawater (pore water) extracted from exposed sponges rose from ambient 3.5% to 4.348% after 1 h, to 5.1–5.9% after 6 h. Most endobionts died or left their host during this last phase. Natural vertical zonation in these sponges reflects their resistance to tidal exposure.  相似文献   
16.
Abstract. In the Sicilian lagoon Stagnone di Marsala, Tethya aurantium and T. citrina show different ecological distributions, although some overlapping occurs. The first species reaches its highest density where linear currents are maximal, and in this habitat it is particularly frequent on Posidonia oceanica rhizomes. The second species is more abundant in still water locations and is equally common on Posidonia rhizomes and on calcareous concretions. Such distributions can be related to water movement, Posidonia shoot density, and associated factors such as sedimentation and food availability. These observations are consistent with an adaptive interpretation of the morphofunctional features distinguishing the two species.  相似文献   
17.
Abstract Sponge bioerosion is a result of tissue expansion of endolithic sponges in calcium carbonate substrates. The efficiency of erosion by the sponges can be affected by substrate features, which are thus also likely to influence the way in which the sponge will grow. A field experiment was conducted, in which sponge tissue was grafted to biogenic blocks cut from the corals Goniopora tenuidens, massive Porites sp., Astreopora listeri, Favites halicora, Favia pallida, Goniastrea retiformis and Cyphastrea serailia, and the clam Tridacna squamosa, to investigate colonisation capabilities and growth patterns of Cliona orientalis Thiele, 1900 after 9 months of the experiment. C. orientalis is not substrate‐specific. It invaded > 90 % of the different substrate blocks and penetrated them to varying depths, but usually only down to slightly more than 1 cm. Lateral penetration clearly exceeded depth penetration. Enlargement of surface area versus restricted depth penetration benefits the symbiotic zooxanthellae located in the sponge's surface. Structural irregularities and barriers such as coral dissepiments temporarily deflected the direction of tissue growth and created characteristic tissue patch patterns in different substrates. Tissue growth may be more pronounced in substrates of higher density and lower pore volume, but evidence was only slight. Protection against predation is better in denser materials, which may stimulate the sponge's tissue growth especially in shallower substrate depth. In more porous substrates, favoured by grazers and corallivores, relatively more tissue was located in deeper layers.  相似文献   
18.
The Mediterranean coralligenous substratum is a hard bottom of biogenic origin, mainly composed of calcareous algae, growing in dim light conditions. Sponges are among of the most representative taxa of the coralligenous assemblages, with more than 300 recorded species of different habits: massive, erect, boring and insinuating. When sponges die, their siliceous spicules remain trapped in the biogenic concretion, offering the opportunity to describe the coralligenous spongofauna over a very long span of time, virtually dating back to a large part of the Holocene period. The data reported here were obtained from core samples collected from four coralligenous concretions. Each block was collected in a different locality of the Ligurian Sea: Santo Stefano Shoals, Bogliasco, Punta del Faro (Portofino Promontory) and Punta Manara. Radiocarbon age determinations indicate for these conglomerates a maximal age between 1600 and 3100 years. The spicules trapped in the cores show deep dissolution marks in the form of circular holes on their surface or present an enlargement of the axial canal. However, their original shape, generally intact, suggests the absence of mechanical injuries and allows a tentative identification at the species level. The analysis of these old spicules reveals an ancient sponge assemblage composed of 30 recognisable species. This indicates that almost one half of the sponge community today settled on coralligenous substrata has been present in the conglomerates for their entire existence.  相似文献   
19.
Four adult specimens of the pycnogonid Ammothea magniceps were observed swimming at the sea surface at night at Kaikoura. Even after capture the animals continued to swim at the surface of the water for over an hour. Such swimming behaviour is considered important in explaining the presence of “benthic” animals in plankton samples.  相似文献   
20.
A late Paleocene‐early Eocene (c. 60–53 Ma) poriferan fauna, comprising hexactinellids (Class Hexactinellida), astrophorids (Class Demospongiae: Family Astrophorida), and lithistids ("lithistid” Demospongiae) has been identified from the Tutuiri Greensand outcropping on the north coast of Chatham Island, New Zealand. Most of the fossils are hexactinellids, comprising extremely delicate siliceous networks embedded in friable sandstone. The sediment matrix within and around these skeletons contains numerous siliceous demosponge spicules, many of which are exceptionally well preserved. The soft friable matrix of the Tutuiri Greensand has made extraction a relatively simple process, making taxonomic identification of the material, and comparison with adjacent Recent and other New Zealand Eocene faunas possible. These sponge body fossils and spicule microfossils indicate a fauna that was once dominated by hexactinellids, lithistid, and astrophorid demosponges. A qualitative comparison of the abundance and diversity of the Tutuiri Greensand sponge fauna with the present‐day Chatham Rise sponge fauna indicates that the late Paleocene‐early Eocene fauna is as diverse as the Recent fauna, for the hexactinellid sponges and astrophorid demosponges, and much more diverse for lithistid sponges. The paleoecology of the Tutuiri Greensand has been interpreted as inner to mid shelf water depths (50–250 m) but the poriferan fauna described here is more like that of the present‐day soft sediment benthic environment of the Chatham Rise at 800–1200 m.  相似文献   
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