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Updated: Jan 22, 2026
06:48
Assessing Intertidal Populations of the Invasive European Green Crab
Published on: September 16, 2020
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Modelling the functioning of a coupled microphytobenthic-EPS-bacterial system in intertidal mudflats.
C Rakotomalala1, K Guizien2, K Grangeré1
1Laboratoire de Biologie des Organismes et Ecosystèmes Aquatiques (BOREA) Université de Caen-Normandie, Esplanade de la Paix, 14032, Caen, France.
Marine Environmental Research
|July 13, 2019
Summary
This study models microphytobenthos (MPB) interactions with nutrients and bacteria in tidal systems. Findings show carbon and nitrogen ratios drive MPB vertical migration, crucial for benthic ecosystem functioning.
Area of Science:
- Marine ecology
- Biogeochemistry
- Microbial ecology
Background:
- Microphytobenthos (MPB) are key primary producers in intertidal zones.
- Their vertical migration in sediments influences nutrient cycling and ecosystem dynamics.
- Understanding MPB interactions with nutrients and bacteria is vital for tidal system management.
Purpose of the Study:
- To develop a mechanistic and biogeochemical model of MPB, bacteria, and nutrient interactions in tidal systems.
- To investigate the drivers of MPB vertical migration, including exogenous and endogenous factors.
- To simulate MPB growth phases and the impact of nutrient availability.
Main Methods:
- Developed a mechanistic and biogeochemical model integrating MPB, bacteria, and nutrient dynamics.
- Formulated MPB behavioral vertical migration influenced by tide, light, carbon, and nitrogen.
- Included Extracellular Polymeric Substances (EPS) secretion during photosynthesis and migration.
Main Results:
- Model simulations closely matched observed MPB dynamics, supporting carbon and nitrogen ratios as key migration drivers.
- The model accurately reproduced MPB lag, logarithmic, and plateau growth phases in mesocosm experiments.
- Nutrient availability, potentially enhanced by bioturbation, significantly impacted MPB biomass and development, with depletion causing the plateau phase.
Conclusions:
- Carbon and nitrogen ratios are critical factors in the vertical migration of diatoms within sediments.
- Nutrient availability is a significant determinant of MPB biomass and overall benthic system functioning.
- The model provides valuable insights into benthic ecosystem processes, despite areas for future refinement in EPS and bacterial dynamics.
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