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.

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.

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.

Dynamic Visual Noise Affects Visual Short-Term Memory for Surface Color, but not Spatial Location

2010 ◽  
Vol 57 (1) ◽  
pp. 17-26 ◽  
Author(s):  
Kevin Dent
Keyword(s):  
Short Term Memory ◽  
Spatial Location ◽  
Visual Noise ◽  
Dynamic Visual Noise ◽  
Short Term ◽  
Surface Color ◽  
Term Memory ◽  
Visual Short Term Memory ◽  
Experimental Tool ◽  
Spatial Locations

In two experiments participants retained a single color or a set of four spatial locations in memory. During a 5 s retention interval participants viewed either flickering dynamic visual noise or a static matrix pattern. In Experiment 1 memory was assessed using a recognition procedure, in which participants indicated if a particular test stimulus matched the memorized stimulus or not. In Experiment 2 participants attempted to either reproduce the locations or they picked the color from a whole range of possibilities. Both experiments revealed effects of dynamic visual noise (DVN) on memory for colors but not for locations. The implications of the results for theories of working memory and the methodological prospects for DVN as an experimental tool are discussed.

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.

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