Climate change predictions… How algae help improve accuracy?
There are nearly 12,000 types of algae, covering about 4 million square miles of land, equivalent to the size of Canada.
They are of ecological and evolutionary importance; playing a fundamental role in rainwater retention, reducing plant diseases, increasing carbon sequestration in soil, and thus improving overall soil health.
Algae also protect long-term carbon storage systems, such as swamps and permafrost soil. Algae growth is increasingly used in models to improve climate change predictions. However, the impact of major climate variables, such as elevated carbon dioxide (eCO2) levels, on algae remains unexplored.
Algae face carbon dioxide levels differently than most terrestrial plants. Due to their small size, they grow near the soil surface, exposed to carbon dioxide emitted from the decomposition of organic matter in the soil. Therefore, algae may be exposed to much higher carbon dioxide levels than most other plants.
Unlike flowering plants, algae do not use stomata to take in carbon dioxide. Therefore, their access to available carbon dioxide may be less, raising important and interesting questions about how algae respond to carbon dioxide, whether they benefit from it, and how their response differs from other wild plants.
A collaborative research team from the Pande and Allen labs at the Donald Danforth Plant Science Center in the United States addressed these questions in a study published in the journal ‘New Phytologist.’ They found that the alga ‘Viscumitrium’ gained three times more biomass under elevated carbon dioxide conditions by regulating its growth and metabolism.
Their results demonstrated the flexible response of algae to increased carbon dioxide, with increased biomass resulting from improved photosynthetic processes and a delicate balance in the life cycle transition between widespread and dense growth, depending on the availability of nitrogen and carbon.
Bomminathan Mohnsundaram, the lead author of the study and a postdoctoral scientist in the Pande Lab, stated, ‘Algae are the primary plants that maintain long-term carbon storage systems, such as permafrost and swamps. The algae cover above permafrost soil isolates it from direct sunlight and avoids ice melting. In swamp ecosystems, algae provide suitable conditions for carbon isolation several times. Therefore, algae are relevant to the measures related to the current climate emergency.’
He added, ‘The current research also provides important insights into the growth of algae that may benefit climate change models. It would be useful to expand the range of ideas derived from this study to include the survival, spread, and ability of algae to absorb carbon across a range of soil nitrogen and carbon dioxide systems, undoubtedly helping our understanding of how this important group of plants responds to expected future climate change.’
