A recent study published in Science Advances suggests that plants may absorb more carbon dioxide (CO₂) than previously thought, potentially impacting climate change mitigation strategies. The research found that models accounting for key plant life processes consistently predicted stronger CO₂ uptake, with the most complex model estimating up to 20% more absorption than simpler versions.
Plants absorb CO₂ through photosynthesis, using the Sun’s energy to convert it into sugars for growth and metabolic activities. About half of this absorbed CO₂ is released back into the atmosphere through respiration, while the other half contributes to plant biomass, remaining stored for varying periods. Eventually, this biomass decomposes, releasing some carbon back into the atmosphere, but a portion also enters the soil, potentially remaining there for centuries.
This study’s findings highlight plants’ resilience and underscore the importance of preserving and restoring vegetation to combat climate change. However, it also emphasizes that this does not diminish the urgent need to reduce fossil fuel emissions.
The study involved enhancing the Australian terrestrial biosphere model by incorporating three neglected processes: the efficiency of CO₂ movement inside leaves, plants’ adaptation to temperature changes, and nutrient distribution. These additions were based on the latest data and research, and the model was then subjected to a strong climate change scenario to observe CO₂ uptake until the end of the century.
Eight different model versions were tested, ranging from the simplest, which did not include any of the three mechanisms, to the most complex, which included all. The results consistently showed that models with greater complexity and ecological realism predicted higher CO₂ uptake.
While these findings suggest plants could be more resilient to climate change than expected, the study acknowledges that other processes, like the impacts of fires and droughts, are still oversimplified in current models. Therefore, a more comprehensive understanding of how plants will absorb CO₂ in the future is needed.
In conclusion, while plants may be more effective in fighting climate change than previously believed, human action, particularly reducing fossil fuel emissions, remains crucial. Plants cannot shoulder the burden of climate change mitigation alone.