scholarly journals Strategies for Successful Scallops Spat Collection on Artificial Collectors in the Taranto Gulf (Mediterranean Sea)

Water ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 462
Author(s):  
Loredana Papa ◽  
Ermelinda Prato ◽  
Francesca Biandolino ◽  
Isabella Parlapiano ◽  
Giovanni Fanelli
Keyword(s):  
Mediterranean Sea ◽  
Immersion Time ◽  
Settlement Patterns ◽  
Marine Invertebrates ◽  
High Variability ◽  
Harvest Rate ◽  
Spat Collection ◽  
Natural Recruitment ◽  
Recruitment Period ◽  
Pelagic Larval Stage

The high variability in natural recruitment of Pectinidae is a common feature of many marine invertebrates with a pelagic larval stage, but may negatively affect aquaculture activities. Detailed information on settlement patterns and spat availability is required to reduce costs and labor. In this regard, we attempted to establish the precise immersion time and the deployment dates for spat collectors in the Taranto Gulf (Mediterranean Sea, Italy). The first experiment was carried out from June to October 2013, deploying collectors every 15 days and retrieving them after 4, 6, 8, and 10 weeks. Results from the first experiment allowed us to select 8 weeks as the best immersion time for spat collection. The second experiment was carried out from June 2013 to July 2014 when we deployed spat collectors every 15 days and recovered them after 8 weeks to detect the favorable periods to place the collectors in water to obtain the highest scallop spat harvest rate. Mimachlamys varia was the most abundant pectinid (greater than 90%), whose recruits were collected during most of the year studied, followed by Flexopecten glaber with the highest rates in July (87%) and Pecten jacobaeus, which never exceeded 17% of collected spat. M. varia had a long recruitment period (from October to early June), F. glaber showed a high number of spat during autumn months and from June to July while P. jacobaeus showed a restricted period of spawning. Our experiments provide useful insights into strategies for establishing scallop aquaculture in order to promote these mollusks as alternative candidates for aquaculture farming in the area.

scholarly journals Atmospheric deposition of organic matter at a remote site in the central Mediterranean Sea: implications for the marine ecosystem

2020 ◽  
Vol 17 (13) ◽  
pp. 3669-3684 ◽  
Author(s):  
Yuri Galletti ◽  
Silvia Becagli ◽  
Alcide di Sarra ◽  
Margherita Gonnelli ◽  
Elvira Pulido-Villena ◽  
...  
Keyword(s):  
Time Series ◽  
Organic Matter ◽  
Atmospheric Deposition ◽  
Mediterranean Sea ◽  
High Variability ◽  
Saharan Dust ◽  
Organic Substances ◽  
Remote Site ◽  
Central Mediterranean ◽  
Central Mediterranean Sea

Abstract. Atmospheric fluxes of dissolved organic matter (DOM) were studied for the first time on the island of Lampedusa, a remote site in the central Mediterranean Sea (Med Sea), between 19 March 2015 and 1 April 2017. The main goals of this study were to quantify total atmospheric deposition of DOM in this area and to evaluate the impact of Saharan dust deposition on DOM dynamics in the surface waters of the Mediterranean Sea. Our data show high variability in DOM deposition rates without a clear seasonality and a dissolved organic carbon (DOC) input from the atmosphere of 120.7 mmol DOC m−2 yr−1. Over the entire time series, the average dissolved organic phosphorus (DOP) and dissolved organic nitrogen (DON) contributions to the total dissolved pools were 40 % and 26 %, respectively. The data on atmospheric elemental ratios also show that each deposition event is characterized by a specific elemental ratio, suggesting a high variability in DOM composition and the presence of multiple sources. This study indicates that the organic substances transported by Saharan dust on Lampedusa mainly come from a natural sea spray and that Saharan dust can be an important carrier of organic substances even though the load of DOC associated with dust is highly variable. Our estimates suggest that atmospheric input has a larger impact on the Med Sea than on the global ocean. Further, DOC fluxes from the atmosphere to the Med Sea can be up to 6 times larger than total river input. Longer time series combined with modeling would greatly improve our understanding of the response of DOM dynamics in the Med Sea to the change in aerosol deposition pattern due to the effect of climate change.

scholarly journals Atmospheric deposition of organic matter at a remote site in the Central Mediterranean Sea: implications for marine ecosystem

2020 ◽  
Author(s):  
Yuri Galletti ◽  
Silvia Becagli ◽  
Alcide di Sarra ◽  
Margherita Gonnelli ◽  
Elvira Pulido-Villena ◽  
...  
Keyword(s):  
Time Series ◽  
Organic Matter ◽  
Atmospheric Deposition ◽  
Mediterranean Sea ◽  
High Variability ◽  
Saharan Dust ◽  
Organic Substances ◽  
Remote Site ◽  
Central Mediterranean ◽  
Central Mediterranean Sea

Abstract. Atmospheric fluxes of dissolved organic matter (DOM) were studied for the first time at the Island of Lampedusa, a remote site in the Central Mediterranean Sea (Med Sea), close to the Sahara desert, between 19 March 2015 and 1 April 2017. The main goals of this work are: to quantify total atmospheric deposition of DOM in this area and to evaluate the impact of dust deposition on DOM dynamics in the surface waters of the Mediterranean Sea. Our data show high variability in DOM deposition rates without a clear seasonality and allow to estimate a dissolved organic carbon (DOC) input from the atmosphere of 120.7 mmol DOC m−2 yr−1. Over the entire time-series, the average dissolved organic phosphorous (DOP) and dissolved organic nitrogen (DON) contributions to the total dissolved pools were 40 % and 26 %, respectively. The data on atmospheric elemental ratios also show that each deposition event is characterized by a specific elemental ratio, suggesting a high variability in DOM composition and the presence of multiple sources. This study indicates that the organic substances transported by Saharan dust at Lampedusa site mainly have natural origin, especially from sea spray and that Saharan dust can be an important carrier of organic substances, even if the load of DOC associated with dust is highly variable. Our estimates suggest that atmospheric input has an impact to the Med Sea larger than to the global ocean and that DOC fluxes from the atmosphere to the Med Sea can be up to 6-fold larger than river input. Longer time series, combined with a modelling effort, are therefore mandatory in order to investigate the response of DOM dynamics in the Med Sea to the change in aerosol deposition pattern due to the effect of climate change.

Reproductive Patterns and Tidal Effects on Spat Settlement of Mytilus Edulis Populations in Dundrum Bay, Northern Ireland

1997 ◽  
Vol 77 (1) ◽  
pp. 229-243 ◽  
Author(s):  
L.M. Snodden ◽  
D. Roberts
Keyword(s):  
Northern Ireland ◽  
Settlement Patterns ◽  
Size Range ◽  
Gonad Development ◽  
Population Differences ◽  
Tidal Effects ◽  
Main Development ◽  
Spat Collection ◽  
Spat Settlement ◽  
Reproductive Cycles

The gametogenic and spat settlement patterns of two Mytihis edulis beds were studied in Dundrum Inner Bay, Northern Ireland. There was evidence of gonad development throughout the year with the main development period between November and March. Spawning was protracted, lasting from May to November. Slight inter-annual and inter-population differences in the riming of the phases were observed but the cycles at both beds were broadly similar to each other and to those of other British and Irish sites. Settlement occurred throughout the year and there was evidence of both primary and secondary spat settlement at both sites. Although the reproductive cycles were similar, distinct seasonal and inter-site differences in spatfall were apparent. At the Downshire Bridge bed, settlement peaked during summer and was dominated by spat in the 0·;5-1·0 mm size range. At Ballykinler, settlement levels were highest in the winter months and larger (>1 mm) spat dominated the samples. The orientation of spat collection pads also significantly affected numbers of the larger (>1 mm) spat. Collectors facing the flood tide attracted significantly more secondary settlers than ebb-facing collectors. This effect varied seasonally and was greater at the Ballykinler bed. It is suggested that hydrodynamic regimes may be an important factor in the differences in settlement patterns of M. edulis.

Production and Survivorship of Epizoites of the Hydroid Nemertesia Antennina (L.)

1978 ◽  
Vol 58 (2) ◽  
pp. 333-345 ◽  
Author(s):  
R. G. Hughes
Keyword(s):  
Life Span ◽  
Secondary Production ◽  
Marine Invertebrates ◽  
Reasonable Accuracy ◽  
Recruitment Period

The survivorship of marine invertebrates that have a life span of less than 2 years is usually assessed by observing the decrease in abundance of animals from samples taken frequently throughout the life of an identifiable cohort or generation (e.g. Crisp, 1971). This method is only suitable for species with approximately simultaneous recruitment so that the animals can be aged with reasonable accuracy and the mortality before the end of the recruitment period can safely be ignored. Such age-specific survivorship data can be used to calculate secondary production by revealing the number of animals that reach successive weights (= Allen curves) (Crisp, 1971).

scholarly journals Microbiome Analysis Reveals Diversity and Function of Mollicutes Associated with the Eastern Oyster, Crassostrea virginica

mSphere ◽  
2021 ◽  
Vol 6 (3) ◽  
Author(s):  
Zachary T. Pimentel ◽  
Keith Dufault-Thompson ◽  
Kayla T. Russo ◽  
Abigail K. Scro ◽  
Roxanna M. Smolowitz ◽  
...  
Keyword(s):  
Functional Analysis ◽  
Crassostrea Virginica ◽  
Marine Invertebrates ◽  
Eastern Oyster ◽  
High Variability ◽  
Metabolic Reconstruction ◽  
High Prevalence ◽  
Adult Oyster ◽  
Genome Scale

ABSTRACT Marine invertebrate microbiomes play important roles in diverse host and ecological processes. However, a mechanistic understanding of host-microbe interactions is currently available for a small number of model organisms. Here, an integrated taxonomic and functional analysis of the microbiome of the eastern oyster, Crassostrea virginica, was performed using 16S rRNA gene-based amplicon profiling, shotgun metagenomics, and genome-scale metabolic reconstruction. Relatively high variability of the microbiome was observed across individual oysters and among different tissue types. Specifically, a significantly higher alpha diversity was observed in the inner shell than in the gut, gill, mantle, and pallial fluid samples, and a distinct microbiome composition was revealed in the gut compared to other tissues examined in this study. Targeted metagenomic sequencing of the gut microbiota led to further characterization of a dominant bacterial taxon, the class Mollicutes, which was captured by the reconstruction of a metagenome-assembled genome (MAG). Genome-scale metabolic reconstruction of the oyster Mollicutes MAG revealed a reduced set of metabolic functions and a high reliance on the uptake of host-derived nutrients. A chitin degradation and an arginine deiminase pathway were unique to the MAG compared to closely related genomes of Mollicutes isolates, indicating distinct mechanisms of carbon and energy acquisition by the oyster-associated Mollicutes. A systematic reanalysis of public eastern oyster-derived microbiome data revealed a high prevalence of the Mollicutes among adult oyster guts and a significantly lower relative abundance of the Mollicutes in oyster larvae and adult oyster biodeposits. IMPORTANCE Despite their biological and ecological significance, a mechanistic characterization of microbiome function is frequently missing from many nonmodel marine invertebrates. As an initial step toward filling this gap for the eastern oyster, Crassostrea virginica, this study provides an integrated taxonomic and functional analysis of the oyster microbiome using samples from a coastal salt pond in August 2017. The study identified high variability of the microbiome across tissue types and among individual oysters, with some dominant taxa showing higher relative abundance in specific tissues. A high prevalence of Mollicutes in the adult oyster gut was revealed by comparative analysis of the gut, biodeposit, and larva microbiomes. Phylogenomic analysis and metabolic reconstruction suggested the oyster-associated Mollicutes is closely related but functionally distinct from Mollicutes isolated from other marine invertebrates. To the best of our knowledge, this study represents the first metagenomics-derived functional inference of Mollicutes in the eastern oyster microbiome.

Occurrence of Vibrio parahaemolyticus in selected marine invertebrates, sediment, and seawater around Alexandria, Egypt

1982 ◽  
Vol 28 (11) ◽  
pp. 1261-1264 ◽  
Author(s):  
M. A. El-Sahn ◽  
A. A. El-Banna ◽  
A. M. El-Tabey Shehata
Keyword(s):  
Mediterranean Sea ◽  
Vibrio Parahaemolyticus ◽  
Marine Invertebrates ◽  
Sea Urchins ◽  
Donax Trunculus ◽  
The Mediterranean

Samples of seawater, sediment, and the following invertebrates were collected from the Mediterranean Sea in the neighborhood of Alexandria, Egypt: sea urchins (Echinus spp.), clams (Tapes spp.), and wedge shells (Donax trunculus). A total of 165 samples were collected from November 1979 to July 1980. Average counts (per 100 mL or 100 g) of Vibrio parahaemolyticus content were as follows: seawater, 36; sea urchins, 349; sediment, 436; wedge shells, 534; clams, 1872. Samples collected in the summer months contained higher levels of V. parahaemolyticus than winter samples.

scholarly journals Jellyfish Bioprospecting in the Mediterranean Sea: Antioxidant and Lysozyme-Like Activities from Aurelia coerulea (Cnidaria, Scyphozoa) Extracts

Marine Drugs ◽  
2021 ◽  
Vol 19 (11) ◽  
pp. 619
Author(s):  
Loredana Stabili ◽  
Lucia Rizzo ◽  
Rosa Caprioli ◽  
Antonella Leone ◽  
Stefano Piraino
Keyword(s):  
Mediterranean Sea ◽  
Bioactive Compounds ◽  
Coastal Waters ◽  
Marine Invertebrates ◽  
Coastal Lagoons ◽  
Complex Mixture ◽  
High Abundance ◽  
Moon Jellyfish ◽  
Aurelia Coerulea ◽  
The Mediterranean

Marine invertebrates represent a vast, untapped source of bioactive compounds. Cnidarians are represented by nearly 10,000 species that contain a complex mixture of venoms, collagen, and other bioactive compounds, including enzymes, oligosaccharides, fatty acids, and lipophilic molecules. Due to their high abundance in coastal waters, several jellyfish taxa may be regarded as candidate targets for the discovery of novel lead molecules and biomaterials and as a potential source of food/feed ingredients. The moon jellyfish Aurelia coerulea is one of the most common jellyfish worldwide and is particularly abundant in sheltered coastal lagoons and marinas of the Mediterranean Sea, where it first appeared—as an alien species—in the last century, when Pacific oyster cultivation began. In the present study, the antioxidant and lysozyme antibacterial activities associated with extracts from different medusa compartments—namely the umbrella, oral arms, and secreted mucus—were investigated. Extracts from the oral arms of A. coerulea displayed significant antioxidant activity. Similarly, lysozyme-like activity was the highest in extracts from oral arms. These findings suggest that A. coerulea outbreaks may be used in the search for novel cytolytic and cytotoxic products against marine bacteria. The geographically wide occurrence and the seasonally high abundance of A. coerulea populations in coastal waters envisage and stimulate the search for biotechnological applications of jellyfish biomasses in the pharmaceutical, nutritional, and nutraceutical sectors.

Skeletal elements of crinoid echinoderms: High-resolution structural and microanalytical results

1983 ◽  
Vol 41 ◽  
pp. 194-195
Author(s):  
D. F. Blake ◽  
L. F. Allard ◽  
D. R. Peacor
Keyword(s):  
High Resolution ◽  
Marine Invertebrates ◽  
Sea Urchins ◽  
Structural Features ◽  
Sea Stars ◽  
High Resolution Tem ◽  
Relationship Of ◽  
The Relationship ◽  
Insight Into

Echinodermata is a phylum of marine invertebrates which has been extant since Cambrian time (c.a. 500 m.y. before the present). Modern examples of echinoderms include sea urchins, sea stars, and sea lilies (crinoids). The endoskeletons of echinoderms are composed of plates or ossicles (Fig. 1) which are with few exceptions, porous, single crystals of high-magnesian calcite. Despite their single crystal nature, fracture surfaces do not exhibit the near-perfect {10.4} cleavage characteristic of inorganic calcite. This paradoxical mix of biogenic and inorganic features has prompted much recent work on echinoderm skeletal crystallography. Furthermore, fossil echinoderm hard parts comprise a volumetrically significant portion of some marine limestones sequences. The ultrastructural and microchemical characterization of modern skeletal material should lend insight into: 1). The nature of the biogenic processes involved, for example, the relationship of Mg heterogeneity to morphological and structural features in modern echinoderm material, and 2). The nature of the diagenetic changes undergone by their ancient, fossilized counterparts. In this study, high resolution TEM (HRTEM), high voltage TEM (HVTEM), and STEM microanalysis are used to characterize tha ultrastructural and microchemical composition of skeletal elements of the modern crinoid Neocrinus blakei.

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