Shellfish as a bioremediation tool: A review and meta-analysis

Area of Science:

• Ecology
• Environmental Science
• Biogeochemistry

Background:

• Human activities have increased nutrient inputs, disrupting nitrogen (N) and phosphorus (P) cycles in ecosystems.
• Reef-forming shellfish (oysters, mussels) are crucial for nutrient cycling, especially N removal via denitrification.
• Understanding environmental influences on shellfish nutrient cycling is vital for bioremediation strategies.

Approach:

• Conducted a qualitative review of nutrient processes on shellfish.
• Performed a meta-analysis on shellfish impact on benthic metabolism and nutrient cycling.
• Evaluated environmental factors: grain size, seasonality, water body type, and tidal position.

Key Points:

• Shellfish increased oxygen consumption, releasing ammonia (NH4) and phosphate (PO43-).
• Phosphate release varied seasonally, peaking in summer and autumn.
• Shellfish enhanced denitrification (N2 efflux), influenced by water body type, sediment, and season.

Conclusions:

• Environmental context significantly mediates shellfish reef effects on sediment function.
• Shellfish bioremediation potential varies with factors like season, sediment grain size, and tidal position.
• Shellfish reefs are valuable tools for aquatic ecosystem nutrient management and remediation.