A new coastal marine ecosystem model study coupled with hydrodynamics and tidal flat ecosystem effect

Area of Science:

• Marine Ecology
• Oceanography
• Environmental Modeling

Background:

• Coastal marine ecosystems face challenges from oxygen depletion and nutrient pollution.
• Understanding the complex interactions between pelagic and benthic systems is crucial for effective management.
• Existing models often lack the integration of tidal flat ecosystems, limiting their predictive power.

Purpose of the Study:

• To develop and apply an integrated coastal marine ecosystem model for Mikawa Bay, Japan.
• To investigate the flux dynamics of carbon, nitrogen, phosphorus, and oxygen.
• To assess the impact of tidal flat ecosystems on water quality and estuarine processes.

Main Methods:

• Developed a coupled pelagic-benthic ecosystem model.
• Incorporated biochemical and physical interactions of dissolved oxygen and C-N-P species.
• Integrated a tidal flat ecosystem model to simulate water purification processes.

Main Results:

• The model identified oxygen-depleted water at the sea-bottom, particularly in summer, due to increased benthic oxygen consumption and reduced vertical mixing.
• Coupling pelagic and benthic systems revealed the significance of sedimentation and nutrient diffusion.
• Simulations demonstrated that tidal flats significantly improve water quality by purifying water and reducing detritus sedimentation.

Conclusions:

• Tidal flats play a vital role in mitigating oxygen depletion and preventing red tides in coastal areas.
• The integrated model provides a valuable tool for understanding and managing coastal marine ecosystems.
• Restricting detritus sedimentation by tidal flats is key to preventing hypoxia in coastal systems like Mikawa Bay.