scholarly journals Using a thermistor flowmeter with attached video camera for monitoring sponge excurrent speed and oscular behaviour

PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e2761 ◽  
Author(s):  
Brian W. Strehlow ◽  
Damien Jorgensen ◽  
Nicole S. Webster ◽  
Mari-Carmen Pineda ◽  
Alan Duckworth
Keyword(s):  
Suspended Sediment Concentration ◽  
Time Lapse ◽  
Video Camera ◽  
Sediment Concentration ◽  
Marine Sponges ◽  
Short Term ◽  
Cross Sectional ◽  
Pumping Rate ◽  
Pumping Rates ◽  
Pumping Activity

A digital, four-channel thermistor flowmeter integrated with time-lapse cameras was developed as an experimental tool for measuring pumping rates in marine sponges, particularly those with small excurrent openings (oscula). Combining flowmeters with time-lapse imagery yielded valuable insights into the contractile behaviour of oscula inCliona orientalis. Osculum cross-sectional area (OSA) was positively correlated to measured excurrent speeds (ES), indicating that sponge pumping and osculum contraction are coordinated behaviours. Both OSA and ES were positively correlated to pumping rate (Q). Diel trends in pumping activity and osculum contraction were also observed, with sponges increasing their pumping activity to peak at midday and decreasing pumping and contracting oscula at night. Short-term elevation of the suspended sediment concentration (SSC) within the seawater initially decreased pumping rates by up to 90%, ultimately resulting in closure of the oscula and cessation of pumping.

scholarly journals Integrating a thermistor flowmeter and time lapse imagery to monitor sponge (Porifera) behaviour

2016 ◽  
Author(s):  
Brian W Strehlow ◽  
Damien Jorgensen ◽  
Nicole S Webster ◽  
Mari-Carmen Pineda ◽  
Alan Duckworth
Keyword(s):  
Spatial Resolution ◽  
Suspended Sediment Concentration ◽  
Time Lapse ◽  
Sediment Concentration ◽  
Marine Sponges ◽  
Short Term ◽  
Experimental Tool ◽  
Pumping Rates ◽  
Pumping Activity ◽  
Cliona Orientalis

A digital, four-channel thermistor flowmeter was developed as an experimental tool for measuring pumping rates in marine sponges, particularly those with small excurrent pores (oscula). The flowmeter is integrated with time lapse cameras and has an accuracy of ±5 mm s-1 over the range of 5–200 mm s-1, a spatial resolution of 1.4 mm, and an adjustable temporal resolution of 5 seconds. Combining flowmeters with time lapse imagery yielded valuable insights into the contractile behaviour of oscula in Cliona orientalis, revealing four distinct oscula states: (1) osculum open with extended papilla, (2) osculum closed with extended papilla, (3) osculum closed with papilla retracted, and (4) osculum closed with papilla retracted and contraction of region surrounding osculum. Osculum area was positively correlated to measured excurrent velocities, indicating that sponge pumping and osculum contraction are coordinated behaviours. Diel trends in pumping activity and osculum contraction were also observed, with sponges increasing their pumping activity to peak at midday and decreasing pumping and contracting oscula at night. Short-term elevation of the suspended sediment concentration within the seawater initially decreased pumping rates by up to 90%, ultimately resulting in closure of the oscula and cessation of pumping. The thermistor flowmeter developed here will be a valuable tool to monitor behaviour, physiology and ecophysiology of sponges.

scholarly journals Integrating a thermistor flowmeter and time lapse imagery to monitor sponge (Porifera) behaviour

2016 ◽  
Author(s):  
Brian W Strehlow ◽  
Damien Jorgensen ◽  
Nicole S Webster ◽  
Mari-Carmen Pineda ◽  
Alan Duckworth
Keyword(s):  
Spatial Resolution ◽  
Suspended Sediment Concentration ◽  
Time Lapse ◽  
Sediment Concentration ◽  
Marine Sponges ◽  
Short Term ◽  
Experimental Tool ◽  
Pumping Rates ◽  
Pumping Activity ◽  
Cliona Orientalis

A digital, four-channel thermistor flowmeter was developed as an experimental tool for measuring pumping rates in marine sponges, particularly those with small excurrent pores (oscula). The flowmeter is integrated with time lapse cameras and has an accuracy of ±5 mm s-1 over the range of 5–200 mm s-1, a spatial resolution of 1.4 mm, and an adjustable temporal resolution of 5 seconds. Combining flowmeters with time lapse imagery yielded valuable insights into the contractile behaviour of oscula in Cliona orientalis, revealing four distinct oscula states: (1) osculum open with extended papilla, (2) osculum closed with extended papilla, (3) osculum closed with papilla retracted, and (4) osculum closed with papilla retracted and contraction of region surrounding osculum. Osculum area was positively correlated to measured excurrent velocities, indicating that sponge pumping and osculum contraction are coordinated behaviours. Diel trends in pumping activity and osculum contraction were also observed, with sponges increasing their pumping activity to peak at midday and decreasing pumping and contracting oscula at night. Short-term elevation of the suspended sediment concentration within the seawater initially decreased pumping rates by up to 90%, ultimately resulting in closure of the oscula and cessation of pumping. The thermistor flowmeter developed here will be a valuable tool to monitor behaviour, physiology and ecophysiology of sponges.

Effect of suspended sediment on fertilization success in the scleractinian coral Pectinia lactuca

2012 ◽  
Vol 92 (4) ◽  
pp. 741-745 ◽  
Author(s):  
Paul L.A. Erftemeijer ◽  
Mary Hagedorn ◽  
Michael Laterveer ◽  
Jamie Craggs ◽  
James R. Guest
Keyword(s):  
Suspended Sediment ◽  
Scleractinian Coral ◽  
Coral Species ◽  
Suspended Sediment Concentration ◽  
Sediment Concentration ◽  
Fertilization Success ◽  
Coral Recruitment ◽  
Short Term ◽  
Coral Spawning ◽  
Fine Suspended Sediment

The effect of increased levels of suspended sediment on fertilization success in the scleractinian coral Pectinia lactuca was investigated in a laboratory experiment following a mass coral spawning event on reefs off Singapore. Egg–sperm bundles were collected from tank-spawned coral colonies collected from the field several days prior to the anticipated mass spawning. Eggs and sperm from each colony were separated and distributed systematically across replicated treatments (N = 9) with three concentrations of fine suspended sediment. Spawning and embryo development in Pectinia lactuca followed a pattern similar to other scleractinian coral species. There was a significant effect of increased suspended sediment concentration on fertilization success (P < 0.05). Both high- (169 mg l−1) and medium- (43 mg l−1) suspended sediment treatments decreased fertilization success compared to controls. These results imply that increased turbidity levels (whether chronic, such as in the waters around Singapore, or short-term, caused by a dredging operation)—when coinciding with the coral spawning season—may affect the reproductive success of corals and compromise coral recruitment and recovery of degraded reefs.

scholarly journals In situ Pumping Rate of 20 Marine Demosponges Is a Function of Osculum Area

2021 ◽  
Vol 8 ◽  
Author(s):  
Teresa Maria Morganti ◽  
Marta Ribes ◽  
Raz Moskovich ◽  
Jeremy Brian Weisz ◽  
Gitai Yahel ◽  
...  
Keyword(s):  
Cross Sectional Area ◽  
Scaling Exponent ◽  
Sectional Area ◽  
Cross Sectional ◽  
Pumping Rate ◽  
Tropical Regions ◽  
Natural Range ◽  
Pumping Rates ◽  
Benthic Ecosystems

Sponges play a key role in the transfer of energy and nutrients into many benthic ecosystems, and the volume of water they process is an important regulator of these fluxes. Theoretical scaling relationships between sponge volume, osculum cross-sectional area, and pumping rates were recently proposed and confirmed for small sponge specimens in the lab. To examine how these relationships apply to field populations we measured, in situ, the pumping rate (PR) of 20 species representative of different morphologies and host types (high- and low-microbial-abundance, HMA and LMA) from temperate and tropical regions. The total oscula area (∑OSA) increased allometrically with sponge volume (V) exhibiting similar exponents (∑OSA=aVb, b ranging 0.6–0.7) for all species, except for tropical HMAs (b = 0.99). Osculum flow rate (OFR) also increased allometrically with OSA and oscula of the same size pumped at the same rate irrespective of sponge volume. As a result, and in contrast to former reports, the PR of most of the sponges increased allometrically (PR=a∑OSAb) with scaling exponent b≈0.75, whereas PR of tropical HMAs increased isometrically. Osculum jet speed declined with the increase in the OSA for most species. The number of oscula and their OSA were the best predictors of the PR in sponges, explaining 75–94% of the in situ variation in PR throughout the natural range of sponge size. The pumping rate of a sponge population can be estimated by measuring the osculum density and cross-sectional area distribution once the relationships between the OSA and OFR are established for each species.

Neural networks approached for modelling river suspended sediment concentration due to tropical storms

2013 ◽  
Vol 11 (4) ◽  
pp. 457-466
Keyword(s):  
Neural Network ◽  
Neural Networks ◽  
Suspended Sediment ◽  
Suspended Sediment Concentration ◽  
Time Series Data ◽  
Water Discharge ◽  
Sediment Concentration ◽  
Series Data ◽  
Generalized Regression Neural Network ◽  
Event Based

Artificial neural networks are one of the advanced technologies employed in hydrology modelling. This paper investigates the potential of two algorithm networks, the feed forward backpropagation (BP) and generalized regression neural network (GRNN) in comparison with the classical regression for modelling the event-based suspended sediment concentration at Jiasian diversion weir in Southern Taiwan. For this study, the hourly time series data comprised of water discharge, turbidity and suspended sediment concentration during the storm events in the year of 2002 are taken into account in the models. The statistical performances comparison showed that both BP and GRNN are superior to the classical regression in the weir sediment modelling. Additionally, the turbidity was found to be a dominant input variable over the water discharge for suspended sediment concentration estimation. Statistically, both neural network models can be successfully applied for the event-based suspended sediment concentration modelling in the weir studied herein when few data are available.

scholarly journals Getting information on suspended sediments in a large river from acoustic backscatter

2018 ◽  
Vol 40 ◽  
pp. 04017
Author(s):  
Adrien Vergne ◽  
Céline Berni ◽  
Jérôme Le Coz
Keyword(s):  
Suspended Sediment Concentration ◽  
Spatial Information ◽  
Suspended Sediments ◽  
Sediment Concentration ◽  
Large River ◽  
Acoustic Backscatter ◽  
Qualitative Information ◽  
Sediment Size ◽  
The Common

There has been a growing interest in the last decade in extracting information on Suspended Sediment Concentration (SSC) from acoustic backscatter in rivers. Quantitative techniques are not yet effective, but acoustic backscatter already provides qualitative information on suspended sediments. In particular, in the common case of a bi-modal sediment size distribution, corrected acoustic backscatter can be used to look for sand particles in suspension and provide spatial information on their distribution throughout a river crosssection. This paper presents a case-study where these techniques have been applied.

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