Biotechnological Approaches to Ocean Acidification

Why is the Ocean Acidifying?

Burning fossil fuels, such as coal, oil, and natural gas, releases large amounts of carbon dioxide (CO₂) into the atmosphere. Under natural conditions, plants play a crucial role in removing CO₂ from the air through photosynthesis, where they absorb carbon dioxide and release oxygen. However, widespread deforestation caused by human activities significantly reduces the number of trees available to absorb CO₂. Furthermore, rising global temperatures act as a catalase to this reaction. This has led to an increase in CO₂ levels in the atmosphere. 

This excess CO₂ doesn't just stay in the air, it also dissolves into the world's oceans. When carbon dioxide mixes with seawater, it undergoes a chemical reaction that produces carbonic acid and hydrogen ions, which increase the ocean's acidity. 

Impacts on Marine Life

Acids have a chemical tendency to react with basic substances, forming salt and water after doing so. When this occurs in the ocean, carbonic acid reacts with carbonate ions, which are a building block of numerous calcium structures used by marine organisms. Increased ocean acidity levels cause fewer carbonate ions in the water, which make it difficult for animals to create seashells and coral. Some organisms impacted by this are oysters, clams, sea urchins, corals, and certain species of plankton. 

Genetically Modified Organisms 

Scientists are aiming to combat coral bleaching through genetic engineering of the microalgae Symbiodinium, which live symbiotically within coral tissues. These algae are vital for coral health, as they photosynthesize to produce nutrients that sustain corals. Symbiodinium is impacted by rising ocean temperatures and increased acidity, leading to coral bleaching and potential coral death. The research team has identified specific genes in Symbiodinium that could be targeted to enhance their stress tolerance, potentially reducing coral bleaching events. However, further testing is still needed before this genetically engineered algae can be released into natural coral reef environments.

References:

“Biological Response.” NOAA Ocean Acidification Program, oceanacidification.noaa.gov/ocean-acidification-research/ocean-acidification-biological-response/.

NOAA. “What Is Ocean Acidification?” National Ocean Service, NOAA, 16 June 2024, oceanservice.noaa.gov/facts/acidification.html.

“Title: Causes of Ocean Acidification and Its Solutions by Biotechnology Driven Intervention – Institute of Life Sciences, BBSR, Department of Biotechnology.” Ils.res.in, 2024, www.ils.res.in/title-causes-of-ocean-acidification-and-its-solutions-by-biotechnology-driven-intervention/. Accessed 26 May 2025.