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Current trends of space occupation by encrusting excavating sponges on Colombian coral reefs 总被引：1，自引：0，他引：1
Some sponges of the genus Cliona (Porifera, Hadromerida, Clionidae) simultaneously excavate and encrust calcareous substratum, competing aggressively for illuminated space with corals and other organisms. To interpret current trends of reef space occupation, the patterns of distribution and size of three Caribbean species were examined at San Andrés Island and Islas del Rosario in Colombia. While Cliona aprica was ubiquitous, C. caribbaea (= C. langae) preferred deep and protected reef zones, and C. tenuis shallow and wave‐exposed settings. In contrast to the effect on other excavating sponges, chronic exposure to raw sewage did not significantly increase the abundance of the studied sponges. Substratum occupation/availability ratios showed a positive tendency of the sponges toward certain coral skeletons, and a negative or neutral tendency toward calcareous rock, indicating that establishment may be easier on clean, recently dead coral than on older, heavily incrusted substratum. High relief generally limits sponge size to that of the illuminated portions of the substratum. A generally lower proportion of small individuals than of larger ones indicates currently low recruitment rates and low subsequent mortality. Successful events of higher recruitment seem to have occurred for C. tenuis. These are related to the massive acroporid coral die‐off in the early 1980s and to asexual dispersion during storms, resulting in a current 10% substratum cover. Reefs with high coral mortality were and/or are thus more susceptible to colonization and subsequent space occupation by these sponges, although relief may prevent space monopolization. 相似文献
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The present study evaluates the potential of Hymeniacidon heliophila as bioindicator of PAH contamination. For this, concentration of 33 PAH was determined in organisms from sites with different contamination level including the heavily polluted Guanabara Bay, Rio de Janeiro, and less impacted coastal areas. PAH concentration and typology were determined in sponges collected from different depths and in two different seasons. The brown mussel broadly studied as bioindicator was also sampled from the same sites for comparison. Both species provided similar information on total PAH concentration which is related to site contamination level. Sponges, however, revealed slight tendency to accumulation of combustion-derived PAH in relation to petrogenic compounds. Differences in PAH typology between species may derive from the interspecific variation in particle size ingestion. Different hydrocarbon typologies were observed in sponges from dry and wet season and PAH concentration varied with depth. H. heliophila may be used as an alternative approach to investigate the presence and sources of PAH in estuarine areas. 相似文献
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The parrotfish Sparisoma viride often grazes live coral from edges undermined by the Caribbean encrusting and excavating sponge Cliona tenuis. To test whether parrotfish biting action has an effect on the dynamics of the sponge–coral interaction, we manipulated access of parrotfishes to the sponge–coral border in two species of massive corals. When parrotfish had access to the border, C. tenuis advanced significantly more slowly into the coral Siderastrea siderea than into the coral Diploria strigosa. When fish bites were prevented, sponge spread into S. siderea was further slowed down but remained the same for D. strigosa. Additionally, a thinner layer of the outer coral skeleton was removed by bioerosion when fish were excluded, a condition more pronounced in D. strigosa than in S. siderea. Thus, the speed of sponge‐spread and the extent of bioerosion by parrotfish was coral species‐dependent. It is hypothesized that coral skeleton architecture is the main variable associated with such dependency. Cliona tenuis spread is slow when undermining live S. siderea owing to the coral’s compact skeleton. The coral’s smooth and hard surface promotes a wide and shallow parrotfish bite morphology, which allows the sponge to overgrow the denuded area and thus advance slightly faster. On the less compact skeleton of the brain coral, D. strigosa, sponge spread is more rapid. This coral’s rather uneven surface sustains narrower and deeper parrotfish bites which do not facilitate the already fast sponge progress. Parrotfish corallivory thus acts synergistically with C. tenuis to further harm corals whose skeletal architecture slows sponge lateral spread. In addition, C. tenuis also appears to mediate the predator–prey fish–coral interaction by attracting parrotfish biting. 相似文献
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Kayley M. Usher 《Marine Ecology》2008,29(2):178-192
Cyanobacteria have flexible photosynthetic apparatus that allows them to utilise light at very low levels, making them ideal symbionts for a wide range of organisms. Sponge associations with cyanobacteria are common in all areas of the world, but little is known about them. Recent research has revealed new cyanobacterial symbionts that may be host specific and two major clades, ' Candidatus Synechococcus spongiarum ' and Oscillatoria spongeliae , that occur in widely separated geographic locations in unrelated sponge hosts. These clades may represent a cluster of closely related symbiont species, or may be single species that are maintained by periods of horizontal transmission over large distances. Erroneous assumptions regarding the importance of cyanobacterial symbionts to the survival of individual sponges or species may arise from cyanosponges being deemed to be phototrophic or mixotrophic without studies of their photophysiology. This review brings together recent and past research on cyanobacterial associations with sponges, including their biogeography, phylogeny, host specificity, and ecology. 相似文献
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Anne Klöppel Martin Pfannkuchen Annika Putz Peter Proksch & Franz Brümmer 《Marine Ecology》2008,29(2):259-272
Sponges provide the largest number of biologically active natural products known from the marine environment and continue to be a very well studied phylum of marine fauna. The Mediterranean sponge Aplysina aerophoba accumulates brominated isoxazoline alkaloids such as Aplysinamisin-1, Aerophobin-2, Isofistularin-3 and the biotransformation product Aeroplysinin-1, which possesses, for example, antibiotic and cytotoxic properties. Until now, it is still being discussed which organisms – the sponge itself or associated microorganisms – are responsible for metabolite production. For cultivating Aplysina individuals under ex situ conditions, we surveyed relevant ecological factors in situ and controlled them in our aquarium system. We maintained A. aerophoba for more than 9 months and analysed changes of metabolite content and composition, microbial association as well as morphology in situ and ex situ under different light exposure. Although sponges showed slight reduction during maintenance, ex situ cultivation similar to in situ conditions provides a promising method to keep sponges and obtain their bioactive metabolites. 相似文献
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James A. Stoddart 《Marine Ecology》1989,10(2):167-178
Abstract. Techniques of starch-gel electrophoresis were applied in a taxonomic assessment of a difficult group of dictyoceratid sponges. A phylogenetic tree derived from the resultant electrophoretic characters agreed well with a recent taxonomic revision of this group produced in a companion study. However, this must be seen as a preliminary result, as the electrophoretic character set was restricted to only three enzyme systems due to the extensive effects of a nonspecific enzyme which precluded the effective interpretation of most other enzymes assayed. This non-specific enzyme may be linked to a highly developed relationship between this group of sponges and symbiotic cyanobacteria. 相似文献
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James J. Bell 《Marine Ecology》2002,23(4):297-311
Abstract. The sponge communities inhabiting a temperate semi-submerged sea cave were investigated at Lough Hyne Marine Nature Reserve, Co. Cork, Ireland. Thirty-one species of sponge were reported, the majority of which exhibited either an encrusting or massive morphology. Sponge density (averaged over depth) increased with horizontal distance (5 m intervals) into the cave until approximately 30 m, corresponding to the maximum algal intrusion (algal information from Norton et al. , 1971) . Species diversity and richness (averaged over depth) were highest at 10 m horizontal distance from the cave entrance. Variability in sponge density, diversity and richness was observed with increasing vertical depth (0.5 m intervals) at most horizontal intervals sampled (5 m apart). These three variables increased initially with depth, but then decreased towards the seabed. Bray-Curtis Similarity Analysis and Multi-Dimensional Scaling (MDS) showed cave sponge community composition to have greater similarity (50 %) with local loose rock habitats than the nearby cliffs. Similar processes structuring cave and loose rock sponge communities may account for this situation. Information collected from this and previous studies on the biotic (algal communities, other fauna and competition) and abiotic factors (water flow rate, depth, aerial exposure, light, cave morphology, nutrient depletion and humidity) affecting this and other caves is discussed with respect to its influence on the sponges inhabiting different parts of the cave. Although horizontal zonation patterns have been considered analogous to vertical distribution patterns for algal communities (due to similar decreases in light), this was not the case for the studied sponge communities. 相似文献
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Chrysophyte cysts and scales and sponge spicules were enumerated, along with diatoms, from the surface sediments of 102 western
Canadian lakes. The salinities of these lakes ranged from 0.042 to 369 g L−1 in late summer. Sponge spicules and chrysophyte cysts and scales were more common in fresher waters, although chrysophyte
cysts were also present in subsaline and hyposaline waters at lower relative percentages. These siliceous microfossils can
easily be distinguished and counted along with diatom valves, with little extra effort. It is likely that using these additional
indicators will strengthen paleolimnological inferences of past lakewater salinity. 相似文献
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Ludmila Ph. Paradina Natalie N. Kulikova Alexander N. Suturin Yelena V. Saibatalova 《Geostandards and Geoanalytical Research》2004,28(2):225-232
Procedures for sampling, sample preparation and ICP-MS analysis of endemic sponges from Lake Baikal have been developed. Sample decomposition was carried out using an open acid decomposition with ultrasound treatment. The distribution of nineteen elements (Mg, Al, P, Ca, Ti, Mn, Co, Ni, Cu, Rb, Sr, Y, Cd, Ba, La, Ce, Pb, Th and U) in different parts of a sponge's body (outer and inner layers and layers adjacent to the substratum) was studied. Detection limits were determined; these ranged from 0.013 to 4.12 μg g-1 for trace elements and from 23 to 130 μg g-1 for biogenic elements. The degree of elemental uptake by living substances is discussed with regard to the environment. 相似文献