Repeated erosion of cohesive sediments with biofilms
This study aims to explore the interplay between biofilms and erodability of cohesive sediments. Erosion experiments were run in four laboratory annular flumes with natural sediments. After each erosion the sediment was allowed to settle, mimicking intermittent physical processes like tidal currents...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2014-04-01
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| Series: | Advances in Geosciences |
| Online Access: | http://www.adv-geosci.net/39/9/2014/adgeo-39-9-2014.pdf |
| _version_ | 1818135314610257920 |
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| author | K. Valentine G. Mariotti S. Fagherazzi |
| author_facet | K. Valentine G. Mariotti S. Fagherazzi |
| author_sort | K. Valentine |
| collection | DOAJ |
| description | This study aims to explore the interplay between biofilms and erodability of
cohesive sediments. Erosion experiments were run in four laboratory annular
flumes with natural sediments. After each erosion the sediment was allowed
to settle, mimicking intermittent physical processes like tidal currents and
waves. The time between consecutive erosion events ranged from 1 to 12 days.
Turbidity of the water column caused by sediment resuspension was used to
determine the erodability of the sediments with respect to small and
moderate shear stresses. Erodability was also compared on the basis of the
presence of benthic biofilms, which were quantified using a Pulse-Amplitude
Modulation (PAM) Underwater Fluorometer. We found that frequent erosion lead
to the establishment of a weak biofilm, which reduced sediment erosion at
small shear stresses (around 0.1 Pa). If prolonged periods without erosion
were present, the biofilm fully established, resulting in lower erosion at
moderate shear stresses (around 0.4 Pa). We conclude that an unstructured
extracellular polymeric substances (EPS) matrix always affect sediment
erodability at low shear stresses, while only a fully developed biofilm mat
can reduce sediment erodability at moderate shear stresses. |
| first_indexed | 2024-12-11T09:22:33Z |
| format | Article |
| id | doaj.art-5f6eadeadf1c421e97449961aee784e2 |
| institution | Directory Open Access Journal |
| issn | 1680-7340 1680-7359 |
| language | English |
| last_indexed | 2024-12-11T09:22:33Z |
| publishDate | 2014-04-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | Advances in Geosciences |
| spelling | doaj.art-5f6eadeadf1c421e97449961aee784e22022-12-22T01:13:14ZengCopernicus PublicationsAdvances in Geosciences1680-73401680-73592014-04-013991410.5194/adgeo-39-9-2014Repeated erosion of cohesive sediments with biofilmsK. Valentine0G. Mariotti1S. Fagherazzi2Department of Earth and Environment, Boston University, 22015 Boston, USADepartment of Earth and Environment, Boston University, 22015 Boston, USADepartment of Earth and Environment, Boston University, 22015 Boston, USAThis study aims to explore the interplay between biofilms and erodability of cohesive sediments. Erosion experiments were run in four laboratory annular flumes with natural sediments. After each erosion the sediment was allowed to settle, mimicking intermittent physical processes like tidal currents and waves. The time between consecutive erosion events ranged from 1 to 12 days. Turbidity of the water column caused by sediment resuspension was used to determine the erodability of the sediments with respect to small and moderate shear stresses. Erodability was also compared on the basis of the presence of benthic biofilms, which were quantified using a Pulse-Amplitude Modulation (PAM) Underwater Fluorometer. We found that frequent erosion lead to the establishment of a weak biofilm, which reduced sediment erosion at small shear stresses (around 0.1 Pa). If prolonged periods without erosion were present, the biofilm fully established, resulting in lower erosion at moderate shear stresses (around 0.4 Pa). We conclude that an unstructured extracellular polymeric substances (EPS) matrix always affect sediment erodability at low shear stresses, while only a fully developed biofilm mat can reduce sediment erodability at moderate shear stresses.http://www.adv-geosci.net/39/9/2014/adgeo-39-9-2014.pdf |
| spellingShingle | K. Valentine G. Mariotti S. Fagherazzi Repeated erosion of cohesive sediments with biofilms Advances in Geosciences |
| title | Repeated erosion of cohesive sediments with biofilms |
| title_full | Repeated erosion of cohesive sediments with biofilms |
| title_fullStr | Repeated erosion of cohesive sediments with biofilms |
| title_full_unstemmed | Repeated erosion of cohesive sediments with biofilms |
| title_short | Repeated erosion of cohesive sediments with biofilms |
| title_sort | repeated erosion of cohesive sediments with biofilms |
| url | http://www.adv-geosci.net/39/9/2014/adgeo-39-9-2014.pdf |
| work_keys_str_mv | AT kvalentine repeatederosionofcohesivesedimentswithbiofilms AT gmariotti repeatederosionofcohesivesedimentswithbiofilms AT sfagherazzi repeatederosionofcohesivesedimentswithbiofilms |