bluuebunny/crossref_metadata_2025_split huggingface dataset:
Proximate Constituents in the Sea‐grasses Zostera marina and Z. noltii in Ireland: Seasonal Changes and the Effect of Blade Removal
Authors: Dawes Clinton J. , Guiry Michael D. 
Published: May 2008

Abstract. Zostera marina L. from the lower intertidal of Galway Bay and Dingle Harbour, Ireland, showed new blade growth in the winter and spring months, a period of high protein levels (to 22%). Soluble carbohydrates (28–49%) were highest in the rhizome in November and after blade production in May. During the period of blade production or blade removal by means of cropping, soluble carbohydrate levels decreased in the rhizome indicating a storage function. The diminutive upper intertidal species, Z. noltii (Hornem.) Reichb. from Dungarvan Harbour, Ireland, also had highest protein levels in its blades in November and May, but the level of soluble carbohydrates in its rhizome was low compared with the larger species. The study indicates that Z. marina, being a perennial with a rhizome that functions as a storage organ, shows “K” type ecological strategies compared with the smaller species.SummaryProtein as well as soluble and insoluble carbohydrate and lipid levels of the blades, rhizomes, and roots of Zostera marina collected seasonally from Galway Bay and Dingle Harbour, Ireland, were similar to published data for the species and to data of other seagrasses. Protein levels were high in the blades and highest during spring blade growth. Soluble carbohydrate was highest in the rhizome segments during the winter, decreasing during spring blade production or when the blades were cropped. In contrast, the diminutive species Z. noltii did not show a seasonal rise in soluble carbohydrate and its blades tended to have high levels of protein in both fall and spring collections. The storage of soluble carbohydrate and long‐term survival of Z. marina suggests that this species is more a “K” strategist, while Z. noltii appears to be an opportunistic species.
Cotylorhiza tuberculata (Cnidaria: Scyphozoa) ‐ Life History of a Stationary Population
Authors: Kikinger Reinhard 
Published: May 2008

Abstract. The life history of a stationary population of Cotylorhiza tuberculata (Maori, 1778) was studied on the Ionian island of Lefkada, Greece, in 1980 and 1981. Occurrence, growth, maturation, and aging of medusae indicated an annual life cycle of this rhizostomous jellyfish. Ephyrae are liberated during strobilation peaks in spring and summer; exceptionally high growth rates lead to medusa diameters of up to 40 cm after six months. Due to symbiotic zooxanthellae the medusae are potentially autotrophic; P: R values ranged from 0.36 to 1.17. The gonochoristic medusae mature during summer; a sexual dimorphism is evident by brood‐carrying filaments in females. The life span of the medusae is about half a year, while scyphistomae are potentially perennial. The observed annual metagenetic cycle is interpreted as a life history adaptation to a highly seasonal environment.SummaryIn the Ionian Sea the metagenetic cycle of a stationary bay population of Cotylorhiza tuberculata is annual. Strobilation occurs during spring and summer. Rapid growth leads to medusa diameters of up to 40 cm within 6 months. The medusae are potentially autotrophic due to their zooxanthellae. The gonochoristic medusae exhibit sexual dimorphism, and spermatozoa are released as spermatozeugmata. Fertilization is internal, with embryogenesis taking place inside the female moutharm canals. The life span of the medusae is limited by deterioration of somatic tissue to about half a year; no medusae of the bay population survive winter. The planula is the only stage within the metagenetic cycle without zooxanthellae, and infection with algal symbionts occurs in scyphistomae. In the laboratory, the potentially perennial scyphistomae preferentially colonize the underside of hard substrates and reproduce by lateral budding; strobilation is monodiscous.
Reproductive Cycles of the Ascidians Microcosmus sabatieri and Halocynthia papillosa in the Northwestern Mediterranean
Authors: Becerro M. A. , Turon X. 
Published: May 2008

Abstract. The reproductive cycles of Microcosmus sabatieri Roule and Halocynthia papillosa (Linnaeus) (Ascidiacea, Pyuridae) were investigated by means of histological observations of the gonads and gonad index measurements on monthly samples from Northeast Spanish coast populations during 1985. Both species are simultaneous hermaphrodites, and the spawning season lasts for two to three months ‐ between September and November ‐ after the period of highest water‐temperatures in the area. The evolution of the gonads during the whole cycle is markedly different in both species. Spawning time is extended towards summer in H. papillosa and towards winter in M. sabatieri.SummaryThe parameters studied in H. papillosa and M. sabatieri indicate a single spawning season per year in the area studied. Both species are simultaneous hermaphrodites, and gamete release occurred after the period of highest seawater temperatures, with a maximum in September‐October for H. papillosa and in October‐November for M. sabatieri. Moreover, the release is noticeably more rapid in H. papillosa.Mean oocyte diameter and gonad index show a good correlation. The values of the latter were almost twice as high in H. papillosa than in M. sabatieri. Since no development of nutritional tissue has been observed in histological sections, this can reasonably be interpreted as a higher investment in gamete production in H. papillosa.Rapid buildup of the gonad, gradual release of gametes, and low gonad indices occur in M. sabatieri, whereas gradual buildup, rapid release, and higher gonad indices are displayed by H. papillosa. This indicates different reproductive behavior in these species, a conclusion which is confirmed by statistical analyses.
The Distribution of Polychaetes Along Environmental Gradients: An Example from the Or betel I o Lagoon, Italy
Authors: Lardicci C. , Abbiati M. , Crema R. , Morri C. , Bianchi C. N. , Castelli A. 
Published: May 2008

Abstract. Biological zonation in brackish habitats is usually related to the gradients of several factors, of which salinity is often taken as the most important. In contrast, recent papers, mainly on Mediterranean lagoons, have emphasized the role of other factors such as water movement and trophic status. In this paper, the distribution of polychaetes in the Orbetello lagoon (a poly‐hyperhaline pond on the northern Tyrrhenian coast) is compared with the gradients of a number of environmental parameters. Polychaete distribution turned out to be under the control of a variety of highly interrelated factors. The study of biotic zonation as a function of a single driving factor is thus overly simplistic even when dealing with ‘simple’ environments, as lagoons are often defined. Several factors and their synergistic effects must always be taken into account.SummaryA total of 79 species was collected from 13 sites in the Orbetello lagoon, comprising both brackish‐water and marine species as well as a large number of species typical of organically enriched habitats. Through correspondence analysis, three major polychaete assemblages were recognized, linked to three different zones of the lagoon: 1) the channels connecting the lagoon to the sea; 2) the western lagoon; 3) the eastern lagoon (including a small part of the western lagoon situated near the town of Orbetello). Such a zonation was shown ‐ by Trend Surface and linear correlation analyses ‐ to be consistent with the spatial trends of a number of environmental parameters such as vivification/confinement, water movement, dissolved oxygen, poikilohalinity, and poikilothermy (in the order of importance); in contrast, salinity (minimal values), sediment grain size, and primary productivity showed little or no relation to polychaete distribution. However, almost all environmental parameters were significantly correlated with each other, thus making it impossible to identify the principal factor. This demonstrates that biotic zonation cannot be explained as the resultant of the action of a single driving factor (e. g., salinity or confinement), even in environments which are usually considered to be relatively simple from a synecological point of view, such as brackish habitats. Both the synergism among the various abiotic factors and the influence of biotic interactions must always be taken into account.
Spawning and Dispersal in Ciona intestinalis (L.)
Authors: Svane Ib , Havenhand Jon N. 
Published: May 2008

Abstract. Oviparous solitary ascidians, such as Ciona intestinalis (L.), generally spawn freely into the water‐column where the eggs are fertilized and develop into free‐swimming non‐feeding larvae. In the laboratory, both spawning and settlement are controlled by light. It has been suggested that both spawning and development time are synchronized so that larval settlement takes place under optimal light conditions in the middle of the day when larvae are best able to locate shaded habitats. Our observations of field populations, however, have shown that Ciona may spawn and settle at any time of the day. Freely spawned eggs, which are negatively buoyant and slightly adhesive, may become attached to any available substratum. Ova can also be released in mucus strings which are particularly adhesive and will readily adhere to adult Ciona and other surfaces. In all cases, fertilization and development proceed normally. Laboratory investigations have shown that newly hatched larvae may either escape to the plankton or be retained in the mucus string until settlement. Thus, the dense aggregations of both adults and newly settled Ciona which are commonly observed in the field could be explained by abbreviated dispersal due to mucus string spawning and epibenthic retention of eggs.SummaryIn the field, Ciona intestinalis embryos at different developmental stages are found simultaneously, indicating that spawning is not confined to a specific time of day. Free eggs are negatively buoyant and slightly adhesive. Eggs are spawned in mucus strings, where fertilization and development takes place. Such strings are retained epibenthically. Settlement and subsequent metamorphosis takes place in the mucus strings, but in the laboratory 40 to 60 % of the larvae escape to the plankton. The aggregation of both adult and juvenile Ciona observed in the field can be explained by mucus string spawning and epibenthic retention of eggs.
Microbial Shell Destruction in Deep‐Sea Mussels, Florida Escarpment
Authors: Hook James E. , Golubic Stjepko 
Published: May 2008

Abstract.Two distinctive patterns of microbial destruction of mineral shell in mussels from the Florida Escarpment (3266 m water depth) are described. One pattern follows a surfacial selective removal of intercrystalline organic matrix creating caries‐like pits. Pitting of the shell resembles spreading bacterial colonies and results in substantial thinning of the original shell. The second pattern consists of an extensive system of sacs with branched and tapered extensions penetrating deep into the shell. Both activities are carried out by unknown microbial agents on live mussels, as evidenced by the presence of repair nacre, which often underlies effected areas. Shell destruction is primarily biological, providing conditions for enhanced chemical dissolution of the mineral shell.SummaryDamage and removal of the protective periostracum layer of deep‐sea mussels by various eukaryotic and prokaryotic microorganisms (Hook& Golubic, 1988, 1990, 1992) exposes the mineral portion of the shell to microbial destruction. This biogenic destruction exceeds the rates of inorganic carbonate dissolution in the area of study. Two types of destructive agents attack the shells of live mussels. The first type forms shallow caries along the interface between periostracum and the mineral shell, primarily attacking intercrystalline organic matrix. The second type represents boring microorganisms, morphologically similar to chytrids, that penetrate and permeate the entire mineral portion of the shell. These activities significantly weaken the shell structure and increase its internal porosity.
Distribution and Abundance of Calyco‐phores (Siphonophora, Calycophorae) in the Mediterranean and Adriatic Sea
Authors: Gamulin Tomo , Kršinic Frano 
Published: May 2008

Abstract. The paper presents data on the distribution of calycophores in the open Mediterranean waters based on samples collected during the R/V “Atlantis II” cruise in May‐June 1969, as well as the first data on the distribution and quantity of nectophores and gonophores in the coastal and open Adriatic waters. The following species were numerically important in the eastern Mediterranean: Eudoxoides spiralis, Bassia bassensis, Sulculeoaria chuni, Lensia campanella, and Diphyes dispar. In the western part of the study area, however, calycophores were found in low numbers. The presence of the immigrating Atlantic forms, Muggiaea atlantica and Lensia subtiloides, was also registered. Among 22 Adriatic calycophores, numerically important were: Muggiaea kochi, Lensia subtilis, Sphaeronectes gracilis, and S. irregularis. Other species were rarely found and mainly distributed in the Otranto Strait and the Southern Adriatic Pit.SummaryThis paper presents data on calycophores found in samples taken during the R/S “Atlantis II” cruise from Rhodos to Gibraltar in May–June 1969, the seasonal cruises along the eastern Adriatic coast in 1973/74, and those in the open Adriatic waters in 1974–1976.In the eastern Mediterranean the species E. spiralis, B. bassensis, S. chuni, L. campanella, and D. dispar were numerically important. In contrast, calycophores were not as abundant in the western Mediterranean. However, the presence of the immigrating Atlantic forms M. atlantica and L. subtiloides was registered.In the Adriatic Sea as many 22 species were found; the most widespread and numerically important were M. kochi, L. subtilis, S. gracilis, and S. irregularis.The dominant species M. kochi contributed from 57 to 87% to the total number of nectophores. Other species were rarely present or of smaller quantitative importance and were mainly distributed in the Otranto Strait and the South Adriatic Pit; north of the Ancona‐Losinj profile these forms were not registered at all.A statistically significant positive correlation between the quantity of nectophores and sexual persons of gonophores was determined. Gonophores were more abundant than nectophores throughout the study period. They were especially numerous during the warmer months.
Seasonality and Reproductive Phenology of Algae Inhabiting Littoral Pools in the Western Mediterranean
Authors: Benedetti‐Cecchi Lisandro , Cinelli Francesco 
Published: May 2008

Abstract.This paper reports on a one‐year investigation carried out inCystoseira‐dominated littoral pools from the west coast of Italy.The seasonal occurrence of the algae and their reproductive characteristics are described. The importance of environmental factors and recruitment processes in determining algal distribution and abundance are also discussed.SummaryAlgal seasonality and reproductive phenology was studied inCystoseira‐dominated tidepools from July 1989 to July 1990. Algae were collected monthly, sorted to species, and checked for reproductive structures. The data were analyzed by means of multivariate techniques (PCA and cluster analysis).Seasonal fluctuations were more evident for annual and ephemeral algae, with peaks in abundance during the summer, while perennial algae showed a slight decline in winter because of storms. Among the 66 taxa recorded, 26 algae were found to be fertile at least once during the study year. These species showed a considerable variation in the seasonal periodicity of reproduction.We suggest that the seasonal patterns of the assemblage were mainly regulated by physical factors, because herbivores were virtually absent in the investigated pools. Moreover, the periodicity of algal reproduction could also have an effect. Since the pool of propagules available to colonize newly disturbed areas changes through time according to the reproductive phenology of the algae and varies so widely, early successional sequences may be governed by the disturbance regime and propagule availability.
A Simulation Model of a Deep Meiobenthic Compartment: A Preliminary Approach
Authors: de Bovee F. , Labat J. Ph. 
Published: May 2008

Abstract. On the basis of data obtained during the ECOMARGE programme and during an annual survey of a deep station (910 m), a first attempt at modelling the carbon flux through a simplified benthic system is presented. Three compartments are simulated: organic matter, bacteria, nematodes. Several hypotheses are proposed by the present simulation: constant or seasonal input of organic matter, intra‐compartmental control or lack thereof. The pulses related to the seasonal input of organic matter and to the internal kinetics of the system are described. Nine to 11 mg C · m‐2· d‐1 are necessary to equilibrate the carbon budget of this simplified deep‐sea benthic system.SummaryA simulation model is used to estimate the importance of energy transfers which could equilibrate the needs of a deep nematode community in the course of time.The observed values for the compartments are obtained from the annual survey of a deep station (910m) of the ECOMARGE programme. Surface sediment organic matter concentrations ranged from 0.50 % to 0.56 % sediment dry weight (or 67,000 mg C · m‐2 to 75,000 mg C · m‐2, respectively), for a mean near‐bottom flux input of 33g C · m‐2· a‐1 (90mg · m‐2· d‐1). The mean organismal biomass approximated to 30 mg C · m‐2 for the bacteria and 37 mg C · m‐2 for the meiofauna.In the simulations, when 9–11% of the input flux are used by the system (9–10 mg C · m‐2· d‐1), the meiofauna compartment is maintained close to the osberved level, while bacterial biomass (9 mg C · m‐2) is lower than the observed value. At lower rates (<8%), the meiobenthic compartment disappears, at higher rates (> 12%) the simulated biomasses show unrealistic values. With a seasonal input flux, the periods of the meiofauna biomass pulses correspond well with the observed data. The mean time lag between the maximum values of the organic matter input and the simulated maximum biomass is 60 days, slightly smaller than the observed value.
Ecology of the Symbiotic Coral Cladocora caespitosa (L.) (Faviidae, Scleractinia) in the Bay of Piran (Adriatic Sea): I. Distribution and Biometry
Authors: Schiller Christian 
Published: May 2008

Abstract. Cladocora caespitosa is a relatively common, colonial, symbiotic, scleractinian coral in the Mediterranean Sea. It inhabits a wide ecological range: hard and soft bottoms, shallow waters or depths to about 50m, calm water or sites exposed to strong currents and wave action. The present study compares the distribution of this coral at two sites, one shallow (3m — wave exposed) and one deeper (12m — soft bottom).Different parameters including dry weight, volume, and skeletal growth rates were investigated. The polyp biomass, carbon content, and overall area of fully expanded polyps were also measured. Equations are given for the relationship of skeleton diameter to polyp tissue dry weight as well as skeleton diameter to the possible filter area of fully expanded polyps. C. caespitosa harbors a rich community of vagile and sessile organisms within the skeleton. The cryptofauna was sorted to higher taxonomic levels and their biomass determined. Several highly significant linear relationship were found between skeleton dry weight, volume and cryptofauna biomass. Thus, the determination of colony volume allows the prediction of cryptofauna biomass.The interstitial space is dominated by sponges ‐ many of them borers ‐ which erode the corallites close to the living tissue until they break off from the colony. At the deeper sampling site, 26% of all colonies are smaller than 2 cm and 48% are smaller than 5 cm. The fragmentation process is discussed with respect to reproduction.
Interaction Between Macrophytobenthic Groups on the Sublittoral Belt of a Greek Island
Authors: Diappoulis Aristidis , Conides Alexis , Koussouris Theodore 
Published: May 2008

Abstract. The interrelationships between the main phytobenthic groups of Chlorophyceae, Phaeophyceae, and Rhodophyceae around Milos Island, Central Aegean Sea, were studied using standard ecological and mathematical methods. The analysis was based on seasonal sampling of 114 different macrophytobenthic species.The employed ecological indices revealed that the sampling areas located on the north, south, and east side of Milos Island show similar annual fluctuations in abundance and species diversity. The resemblance was particularly high between all stations in October‐February, between south and east stations during May, and between north and east stations during July.Additionally, an annual cycle of group interaction with regard to species diversity and abundance exists between the Chlorophyceae, Rhodophyceae, and Phaeophyceae. The Rhodophyceae are the most abundant and dominant group throughout the year, showing percentages in the samples higher than 70% in all sampling areas.
Early Growth Stages and Ecology of Arbaciella elegans Mortensen (Echinodermata, Echinoidea) in Southern Spain
Authors: Salas C. , Hergueta E. 
Published: May 2008

Abstract. Descriptions of early growth stages of Arbaciella elegans Mortensen, 1910 (Echinodermata, Echinoidea) are given. Three phases of development have been distinguished according to spine morphology and test size: ‘postlarval’, less than 1 mm in size, with a single circle of leaf‐shaped spines; ‘juvenile’, over 1 mm, with new circles of subcylindrical spines added; and ‘adult’, more than 3 mm, with nearly all the spines subcylindrical and several circles of them present.A recruitment during late autumn and winter is demonstrated. According to sea urchin body size, the rhizomes of Posidonia oceanica and the concretions of Mesophyllum lichenoides provide a good shelter for the postlarvae.
Decomposition of Mangrove Wood by Marine Fungi and Teredinids in Belize
Authors: Kohlmeyer J. , Bebout B. , Vlkmann‐Kohlmeyer B. 
Published: May 2008

Abstract.Experiments were conducted to determine the decomposition rate of mangrove wood in two areas of differing water nutrient concentrations. Stakes were prepared from prop roots ofRhizophora inangleand from branches ofAvicennia. ConocarpusandLagguncularia. and tied in the natural habitat at two sites—Man‐of‐war Cay (high nutrient concentrations) and Twin Cays (low nutrient concentrations) — off the Belize coast. The stakes were retrieved after 4–24 months and the vertical zonation and succession of higher marine fungi was recorded. Consumption of wood by shipworms (Teredo bartschi), the major decomposers, was measured by digital analysis of the area of wood consumed by these boring organisms.SummaryA total of 20 species of marineAscomycotina, 2Basidiomycotina, and 6 anamorphic fungi were identified from the experimental stakes. Differences in species composition between the two sites of Twin Cays and Man‐of‐war Cay (Belize) were observed, as well as a certain degree of patterning in the vertical distribution of fungi. AmongAscomycotina, members ofHalosphaerialesshow a definite tendency to thrive at greater depths than other species. Mangrove decomposition by shipworms was clearly higher in the nutrient‐rich waters of Man‐of‐war, where the stakes were already heavily riddled after 8 months and had mostly disappeared after 2 years, while they were still intact at the other site. No significant difference in degradation of the 4 species of mangroves was noted.