In an innovative twist on nature-based climate solutions, the IMARCS Foundation is exploring the untapped potential of giant clams as carbon-negative storage agents. By leveraging a first-of-its-kind methodology that alters water chemistry, this research aims to shed new light on whether these incredible bivalves can do more than strengthen reefs and decorate our oceans— they might help mitigate some of the most pertinent aspects of climate change.
Image Credits: https://www.iflscience.com/to-make-a-better-solar-cell-consult-a-giant-clam-74921
A Fresh Perspective on Carbon Storage
Giant clams are known for their impressive calcium carbonate (CaCO₃) shells, which naturally sequester, or store, carbon. However, these marine creatures also emit CO₂ through respiration and shell precipitation, leading to ongoing debates about their overall impact on carbon cycle dynamics. While previous studies have often painted bivalves as net-positive emitters, carbon-neutral, or only marginally carbon-negative, the IMARCS Foundation team hypothesizes that there’s more to the story.
Our novel approach centers on the idea that tweaking the pH of the water could make a significant difference in keeping the carbon released during shell formation. By increasing pH, more CO₂ remains dissolved in the water, potentially converting into additional carbonate or bicarbonate — which giant clams could then re-use use to further build their shells without letting the carbon molecules dissipate into the atmosphere. Coupled with a slight increase in water temperature, these conditions may create the ideal environment for enhanced carbon uptake and shell growth.
The First-of-Its-Kind Methodology
Our main experiment for testing this hypothesis involves comparing giant clam growth in two full-size tanks under different water conditions. In the control tank, natural seawater parameters are being maintained with a pH around 8 (or slightly lower) and a temperature between 25 to 27°C, representing the status quo where clams are expected to grow normally. In the variable tank, the water is being modified to achieve an average pH of about 8.5, with slight nocturnal fluctuations, and a temperature between 27 to 29°C, using methods such as the addition of calcium hydroxide and protein skimmers to reach the desired pH without needing to add external carbonate. Each tank contains 15 individually tagged clams from three different species to ensure that any differences in growth are due to the altered water conditions rather than species-specific factors.
Constant monitoring is a crucial part of the experiment: pH is measured continuously, alkalinity is checked every 6 to 8 hours, organic parameters are assessed weekly, and clams are being weighed and measured at the beginning, around the 3-month midpoint, and then at regular tri-monthly intervals, with photographs taken to visually document growth differences. All other environmental conditions—such as feeding, tank size, light exposure, and water clarity—are being kept identical between the two setups.
Image Credits: https://newatlas.com/giant-clams-color-displays-solar-cells/41394/
Why This Matters
This pioneering study is more than just an academic exercise. If the hypothesis holds true, the IMARCS Foundation's work could lead to a valuable shift in how we view the role of these marine organisms in addressing climate change. By enhancing the natural carbon sequestration capabilities of giant clams through simple — yet precise — water chemistry adjustments, we might unlock a new, sustainable proof of concept for reducing atmospheric CO₂ levels.
Moreover, the insights gained from this controlled experiment could pave the way for broader applications. Imagine integrated coastal management practices that not only protect marine ecosystems but also actively contribute to carbon capture — a win-win for both nature and our climate.
Looking Ahead
As the experiment will run for at least six months, with the potential to extend up to one year, the data collected will provide robust insights into how targeted environmental modifications affect clam growth and carbon storage. The IMARCS Foundation is poised to contribute valuable data that could help refine our understanding of biogenic carbon sequestration, potentially influencing future climate mitigation strategies.
Stay up to date on our progress by connecting with us on LinkedIn or reaching out to us directly at relationships@imarcs.org