scholarly journals Does Depth Matter? Reproduction Pattern Plasticity in Two Common Sponge Species Found in Both Mesophotic and Shallow Waters

2020 ◽  
Vol 7 ◽  
Author(s):  
Tal Idan ◽  
Liron Goren ◽  
Sigal Shefer ◽  
Itzchak Brickner ◽  
Micha Ilan
Keyword(s):  
Shallow Water ◽  
Reproductive Strategies ◽  
General Rule ◽  
Sponge Species ◽  
Shallow Waters ◽  
Remotely Operated Vehicle ◽  
Oocyte Morphology ◽  
The Face ◽  
Reproduction Pattern ◽  
Temperature Amplitude

Determining demosponge reproductive strategies is essential to understanding their ecology and life history, as well as for the management of benthic marine environments. This is especially important in mesophotic ecosystems, which have been suggested to serve as a refuge for shallow-water populations and for which knowledge is lacking. Here we compared the reproductive strategies of two common Mediterranean demosponges species: Chondrosia reniformis and Axinella polypoides, which can be found in both shallow and mesophotic habitats along the Israeli coast. Samples were collected over 2 years, via SCUBA diving from the shallow coast (2–32 m) and Remotely Operated Vehicle from the mesophotic sponge grounds (95–120 m). A. polypoides and C. renifornis differed in oocyte morphology and development, but both demonstrated reproductive plasticity with regard to temperature and depth: temperature appears to regulate their reproduction in the shallow water, as both species exhibited seasonality; whereas, in the mesophotic zone, where the temperature amplitude is much smaller, seasonality was not observed for either species. Furthermore, in the mesophotic zone, C. reniformis exhibited low fecundity and probably invests more in asexual reproduction by budding. Mesophotic A. polypoides, in contrast, exhibited enhanced and continuous asynchronous sexual reproduction year-round. Our findings suggest that reproduction plasticity may be a general rule for sponge species that inhabit different habitats; such plasticity could allow sponges to thrive in different environmental conditions. These findings further emphasize the importance of protecting the mesophotic sponge grounds, which can serve as a refuge in the face of the adverse impact of anthropogenic disturbances and rising seawater temperatures.

Experimental Study of a Tanker Ship Squat in Shallow Water

2014 ◽  
Vol 66 (2) ◽  
Author(s):  
Mohammadreza Fathi Kazerooni ◽  
Mohammad Saeed Seif
Keyword(s):  
Experimental Study ◽  
Shallow Water ◽  
Experimental Approach ◽  
Model Tests ◽  
Ship Hull ◽  
Experimental Results ◽  
Shallow Waters ◽  
Towing Tank ◽  
Ship Model

One of the phenomena restricting the tanker navigation in shallow waters is reduction of under keel clearance in the terms of sinkage and dynamic trim that is called squatting. According to the complexity of flow around ship hull, one of the best methods to predict the ship squat is experimental approach based on model tests in the towing tank. In this study model tests for tanker ship model had been held in the towing tank and squat of the model are measured and analyzed. Based on experimental results suitable formulae for prediction of these types of ship squat in fairways are obtained.

MODELING MOVING BOUNDARY IN SHALLOW WATER BY LBM

2013 ◽  
Vol 24 (01) ◽  
pp. 1250094 ◽  
Author(s):  
Y. PENG ◽  
J. G. ZHOU ◽  
J. M. ZHANG ◽  
R. BURROWS
Keyword(s):  
Shallow Water ◽  
Present Model ◽  
Moving Boundary ◽  
Lattice Boltzmann Model ◽  
Shallow Waters ◽  
Shallow Water Flows ◽  
Moving Body ◽  
Body Boundary ◽  
Multiple Relaxation Time ◽  
Boltzmann Model

A lattice Boltzmann model (LBM) for a moving body in shallow waters is developed. Three different schemes, FH's, Guo's and MMP's schemes, for a curved boundary condition at second-order accuracy are used in the study and compared in detail. The multiple-relaxation-time (MRT) is adopted for better stability. In order to deal with the moving body boundary, a certain momentum is added to reflect the interaction between the fluid and the solid; and a refill method for new wetted nodes moving out from solid nodes has been proposed. The described method is applied to simulate static and moving cylinders in shallow waters. The corresponding experiments are further performed for validation of the present model. It is found that all of the three schemes produce similar results that agree well with the experimental data for the static cylinder. However, for the moving boundary, MMP's scheme performs best. Overall, the proposed modeling approach is able to simulate both, static and moving cylinders in shallow water flows at acceptable accuracy.

Quantification of Bioerosion by Sphaerechinus Granularis on ‘Coralugène’ Concretions of the Western Mediterranean

1997 ◽  
Vol 77 (2) ◽  
pp. 565-568 ◽  
Author(s):  
Stephane Sartoretto ◽  
Patrice Francour
Keyword(s):  
Shallow Water ◽  
Small Diameter ◽  
Western Mediterranean ◽  
Biological Agent ◽  
High Abundance ◽  
Shallow Waters ◽  
Mean Diameter ◽  
The Mean ◽  
The Mediterranean

Sphaerechinus granularis (Echinodermata: Echinidea) is involved in the erosion of ‘coralligène’ concretions in the Mediterranean. In shallow water (10 m), a high abundance of this species (>20 ind 25 m−2) is associated with small diameter individuals (56·7 ±7·7 mm). In deep clean waters (>40 m), the abundance is lower (<1 ind 25 m−2) and the mean diameter is higher (86·0±9·3 mm). Daily erosion of Corallinaceae by this species is related to the urchin diameter (r=0.87). Local variations in urchin abundance and diameter influence the amount of CaCO3 eroded annually. In shallow waters, the eroded CaCO3 mass reaches 210 g m−2 y−1 vs 16 g m−2 y−1 in coralligène concretions in deep clean waters. Sphaerechinus granularis is an important biological agent which substantially erodes the Mediterranean coralligène concretions.

Life history of Mysis stenolepis Smith (Crustacea, Mysidacea)

1975 ◽  
Vol 53 (7) ◽  
pp. 942-952 ◽  
Author(s):  
T. Amaratunga ◽  
S. Corey
Keyword(s):  
Young Adults ◽  
Life History ◽  
New Brunswick ◽  
Shallow Water ◽  
Field Study ◽  
Sexual Maturity ◽  
Developmental Stages ◽  
Shallow Waters ◽  
Passamaquoddy Bay ◽  
History Of

A 17-month field study showed that Mysis stenolepis in Passamaquoddy Bay, New Brunswick lives for about 1 year. Young are released in shallow water early in spring and grow rapidly during the summer. In the fall, young adults migrate to deeper water where they reach sexual maturity. Transfer of sperm lakes place during winter in deeper regions of the Bay. soon after which the males die. Females survive and in spring migrate to shallow waters to release young after which they die. Females breed once and carry an average of 157 young per brood. Developmental stages of the postmarsupial young are described and discussed.

A first preliminary study of the shallow water sponge fauna from Cyprus Island (Eastern Mediterranean)

Zootaxa ◽  
2018 ◽  
Vol 4450 (5) ◽  
pp. 594
Author(s):  
COSTA GABRIELE ◽  
GIUSSANI VALENTINA ◽  
KLETOU DEMETRIS ◽  
KLEITOU PERIKLIS ◽  
PANSINI MAURIZIO ◽  
...  
Keyword(s):  
Shallow Water ◽  
Mediterranean Sea ◽  
Eastern Mediterranean ◽  
Sponge Species ◽  
Commercial Importance ◽  
The Past ◽  
Number Of Species ◽  
Mediterranean Areas ◽  
The World ◽  
Preliminary Study

Currently, more than 8,500 valid sponge species are reported in the World Porifera Database (http://www.marinespecies.org/porifera/) (van Soest et al. 2018). The Mediterranean Sea sponge fauna, counting almost 700 species, is one of the best documented in the world (Pronzato 2003; Pansini et al. 2011; van Soest et al. 2018) but the eastern part of the basin is by far less studied, in comparison with other Mediterranean areas (Pansini et al. 2000; Voultsiadou & Vafidis 2004; Topaloğlu & Evcen 2014). A small number of species, mainly belonging to the cosmopolitan genus Spongia (Dictyoceratida), are commonly used as bath sponges. Aim of this work is to provide further information on Cyprus Island sponges in general and on species that had commercial importance in the past. 

scholarly journals Recognition of “flowering” processes on the base of remote sensing data in shallow water ponds on the example of the Azov Sea

2020 ◽  
Vol 175 ◽  
pp. 12013 ◽  
Author(s):  
Marina Ganzhur ◽  
Nikita Dyachenko ◽  
Olga Smirnova ◽  
Anna Poluyan ◽  
Natalya Panasenko
Keyword(s):  
Remote Sensing ◽  
Shallow Water ◽  
Satellite Images ◽  
Remote Sensing Data ◽  
Shallow Waters ◽  
Sea Of Azov ◽  
The Sea Of Azov ◽  
Sensing Data ◽  
Azov Sea

This work considers to the processes of «bloom» phytoplankton processes that cause hypoxic phenomena in shallow waters the example of the Sea of Azov. For the accumulation of information, multichannel satellite images of remote sensing are taken as a basis. In the process, the task of programmatically highlighting the contours of the areas of «bloom» is implemented.

Innovative Ice Protection for Shallow Water Drilling: Part I — Presentation of the Concept

2006 ◽  
Author(s):  
Arne Gu¨rtner ◽  
Ove Tobias Gudmestad ◽  
Alf To̸rum ◽  
Sveinung Lo̸set
Keyword(s):  
Shallow Water ◽  
Shallow Waters ◽  
Drilling Rig ◽  
Modular Concept ◽  
Drilling Operations ◽  
Drifting Ice ◽  
Ice Impacts ◽  
Jack Up ◽  
Near Future ◽  
Ice Period

Recent discoveries of hydrocarbons in the shallow waters of the Northern Caspian Sea arise the need for intensive drilling activities to be carried out in the near future in order to explore the potentials. Experience with mobile drilling units in the seasonally ice infested waters solely originates from the current drilling campaign of the Sunkar drilling barge at Kashagan and Kalamkas. However, with increased drilling activities upcoming, innovative drilling concepts are desirable due to the objective of maintaining drilling operations during the ice period with conventional non-ice-resistant drilling platforms. Hence, this paper suggests the employment of external Shoulder Ice Barriers (SIBs) to protect a conventional jack-up drilling rig from the hazards of drifting ice in shallow water. The SIB’s design is suggested to increase the ice rubble generation at the ice facing slope and thereby provide sufficient protection from drifting ice impacts. The modular concept of the SIB makes it possible to deploy each module in a floating mode to site, whereupon they are ballasted and connected to each other, forming a sheltered position for the jack-up. Subsequent to the termination of the drilling campaign the SIB modules may be retrieved by de-ballasting and tow out, without having significant impact on the environment. This paper presents, on a technical feasible level, the concept of ice protection in shallow water by means of SIBs.

The Reproductive Biology of the Deep-Sea Asteroid Bathybiaster Vexillifer

1982 ◽  
Vol 62 (1) ◽  
pp. 57-69 ◽  
Author(s):  
P. A. Tyler ◽  
S. L. Pain ◽  
J. D. Gage
Keyword(s):  
Shallow Water ◽  
Reproductive Biology ◽  
Deep Sea ◽  
Reproductive Strategies ◽  
Ecological Niches ◽  
Physico Chemical ◽  
Males And Females ◽  
Planktotrophic Larvae ◽  
Shallow Water Species ◽  
Water Species

INTRODUCTIONThe reproductive biology of asteroids from a wide variety of ecological niches has been examined (Farmanfarmaian et al. 1958; Cognetti & Delavault, i962;Pearse, 1965; Chia, 1968; Crump, 1971; Jangoux & Vloebergh, 1973; Worley, Franz & Hendler, 1977; Barker, 1979; Shick, Taylor & Lamb, 1981). Most of the species within this class appear to show some degree of seasonal reproductive synchrony with very few species showing aseasonal reproduction (Shick et al. 1981). Although the seasonally reproducing asteroids show a wide variety of reproductive strategies, from planktotrophic larvae to direct development, they all occur in relatively shallow water and are thus subject to the seasonal fluctuations of the physico-chemical environment. Only two shallow-water species, Ctenodiscus crispatus (Shick et al. 1981) and Patiriella exigua (Lawson-Kerr & Anderson, 1978), have aseasonal reproduction in both males and females. However, the deep sea is the only major environment in the world's ocean for which we have no data for the reproductive cycle of asteroids.

scholarly journals Shallow water sponges along the south coast of Java, Indonesia

2018 ◽  
Vol 19 (2) ◽  
pp. 485-493 ◽  
Author(s):  
TRI ARYONO HADI ◽  
MUHAMMAD HAFIZT ◽  
HADIYANTO HADIYANTO ◽  
AGUS BUDIYANTO ◽  
RIKOH MANOGAR SIRINGORINGO
Keyword(s):  
Shallow Water ◽  
Morphological Characters ◽  
South Coast ◽  
Sponge Species ◽  
Marine Biodiversity ◽  
Growth Forms ◽  
The South ◽  
Marine Habitat ◽  
Number Of Species ◽  
Significant Difference

Hadi TA, Hafizt M, Hadiyanto, Budiyanto A, Siringoringo RM. 2018. Shallow water sponges along the south coast of Java, Indonesia. Biodiversitas 19: 485-493. Sponges are the most diverse benthic filter feeders, occupying many different types of marine habitat. The south coast of Java is one such marine habitat, very exposed to the open sea. This study investigated the sponge diversity as well as their morphological characters across the south coast of Java. The observations were carried out from 2011 to 2016 in four different locations, including Pamang Peuk, Gunungkidul, Prigi Bay and Bayuwangi. The study found 96 sponge species, from 15 orders, and described them in terms of nine morphological characters. The most common species included Spheciospongia inconstans, Stylissa massa, Callyspongia sp. and Cinachyrella australiensis, while the most common growth forms were massive and encrusting, accounting respectively for 34.4% and 28.1% of the total number of species. There was a significant difference in the number of species found between sub-tidal and intertidal habitats; subtidal sponges were approximately 50% more diverse than intertidal sponges. Apart from the habitat types, the number of sponges varied in relation to the longitude; east Java had more sponge species with more variations in morphology compared to central and west Java. Encrusting and globular growth forms were the most common characteristics of intertidal sponges in west and central Java, while other growth forms comprised the diverse characteristics of the subtidal sponges in the east Java. This baseline information is essential for management of marine biodiversity hotspots in taking decisions for marine life conservation, because the global trajectory of marine habitat degradation is predicted to rise.

scholarly journals COMPARAÇÃO DA EFICIÊNCIA DE FORRAGEIO DAS GARÇAS EGRETTA CAERULEA E EGRETTA THULA NO ESTUÁRIO DE PARANAGUÁ, PARANÁ, SUL DO BRASIL

2021 ◽  
Vol 25 (01) ◽  
pp. 59-68
Author(s):  
Danila Syriani Veluza ◽  
◽  
Juliana Rechetelo ◽  
Emygdio Leite de Araújo Monteiro-Filho ◽  
Luiz Augusto Macedo Mestre ◽  
...  
Keyword(s):  
Energy Consumption ◽  
Shallow Water ◽  
Capture Efficiency ◽  
Foraging Efficiency ◽  
Shallow Waters ◽  
Success Rates ◽  
Local Conditions ◽  
Foraging Site ◽  
Egretta Thula

The foraging efficiency of birds may vary according to local conditions as a result of the balance between energy consumption and expenditure. The foraging efficiency of Egretta thula (adults n=11) and Egretta caerulea (adults n=69 and juveniles n= 17) was compared in Paranaguá city estuary, in Paraná, Brazil. In 14 hours of observation divided into 2 minutes sessions per individual, were recorded foraging site (mud or shallow water), number of steps, total peckings and successful peckings, and were calculated the success rates, energy effort and capture efficiency. In shallow water E.thula was more efficient than E. caerulea. There was no intraspecific differences in E. thula regarding environments. Adults of E. caerulea were more efficient than juveniles, with greater efficiency in mud than in shallow waters environments. Differences in foraging efficiency between species may be related to the type of foraging according to feeding location.

Sign in / Sign up

Export Citation Format

Share Document