CSIRO Publishing blank image blank image blank image blank imageBooksblank image blank image blank image blank imageJournalsblank image blank image blank image blank imageAbout Usblank image blank image blank image blank imageShopping Cartblank image blank image blank image You are here: Journals > Marine & Freshwater Research   
Marine & Freshwater Research
Journal Banner
  Advances in the Aquatic Sciences
 
blank image Search
 
blank image blank image
blank image
 
  Advanced Search
   

Journal Home
About the Journal
Editorial Board
Contacts
Content
Online Early
Current Issue
Just Accepted
All Issues
Special Issues
Sample Issue
For Authors
General Information
Instructions to Authors
Submit Article
Open Access
For Referees
General Information
Review Article
Referee Guidelines
Early Career Referee Mentoring
Annual Referee Index
For Subscribers
Subscription Prices
Customer Service
Print Publication Dates

blue arrow e-Alerts
blank image
Subscribe to our Email Alert or RSS feeds for the latest journal papers.

red arrow Connect with us
blank image
facebook twitter youtube

 

Article << Previous     |     Next >>   Contents Vol 60(7)

Density-dependent effects of bioturbation by the clam, Scrobicularia plana, on the erodibility of estuarine sediments

Claudia Soares A B, Paula Sobral A

A IMAR – Institute for Marine Research, FCTUNL, Campus da Caparica, 2829-516, Caparica, Portugal.
B Corresponding author. Email: csps@fct.unl.pt
 
PDF (353 KB) $25
 Export Citation
 Print
  


Abstract

Benthic organisms are known to modify sediment properties and influence the flux of materials to the water column. In this study, the density-dependent effects of bioturbation by the estuarine clam, Scrobicularia plana, on the biogeochemical properties and erodibility of the sediment were assessed using laboratory annular flumes. Sediments with different mud contents (~98% and 90%) were collected undisturbed from two different sites of the Tagus estuary. S. plana were added to the sediment at increasing densities (0, 57, 115 and 229 ind m–2) and left to bioturbate the sediment before the experimental erosion runs. All erosion runs were carried out following a stepwise increase of current velocities (U) up to 0.25 m s–1. Sediment chlorophyll a, pheopigments and extracellular polymeric substance fractions were measured at the time of sampling in the field and in the end of the erosion runs. Increasing densities of S. plana in the muddier sediment raised eroded mass, while the sediment with less mud behaved as non-cohesive and registered a decrease in eroded mass possibly due to a switch in the feeding behaviour of S. plana.

Keywords: annular flumes, erosion rates, muddy sediments, Tagus estuary.


   
Subscriber Login
Username:
Password:  

    
Legal & Privacy | Contact Us | Help

CSIRO

© CSIRO 1996-2014