New research reveals plants could absorb more carbon dioxide2 This has exceeded expectations and offers hope in the fight against climate change. However, reducing emissions remains important as tree planting alone is not a sufficient solution.
The new study was published on November 17th. scientific progress It paints an unusual but bright image for the Earth. This is because more realistic ecological modeling suggests that the world’s plants may be able to absorb more of her CO2 from the atmosphere.2 This is more due to human activity than previous predictions.
Despite this headline finding, environmental scientists involved in the study stress that this in no way means that governments around the world can lift the brakes on their obligations to reduce carbon emissions as quickly as possible. There is. While simply planting more trees and protecting existing vegetation is not a definitive solution, the study highlights that protecting such vegetation has multiple benefits.
Understanding CO in plants2 intake
“Plants absorb significant amounts of carbon dioxide (CO2).2) emissions each year, thereby slowing the negative effects of climate change, but it is impossible to predict how long these carbon emissions will last.2 “Future uptake is uncertain,” explains Dr Jürgen Knauer, who led the research team at Western Sydney University’s Hawkesbury Institute for the Environment.
“What we found is that established climate models used in global climate projections, such as those by the IPCC, predict stronger and more sustained carbon uptake through the end of the 21st century.”cent century to explain the influence of some important physiological processes that control plant behavior. photosynthesis.
“We’re learning things like how carbon dioxide can move efficiently inside leaves, how plants adapt to changes in temperature, and how plants most economically distribute nutrients within the canopy. “These are three very important mechanisms that influence the ability of plants to ‘fix’ carbon, but are typically ignored in most global models,” Dr Knauer said. I did.
Photosynthesis and climate change mitigation
Photosynthesis is the scientific term for the process by which plants convert, or “fix”, carbon dioxide.2 It is converted into sugars used for growth and metabolism. This carbon fixation acts as a natural climate change mitigation agent by reducing the amount of carbon in the atmosphere.This is an increase in carbon dioxide intake2 Vegetation is primarily responsible for the increase in terrestrial carbon sinks reported over the past few decades.
However, the beneficial effects of climate change on vegetation carbon uptake may not last forever, and how vegetation responds to carbon dioxide has long been unknown.2, temperature, and precipitation changes are very different from those observed today. Scientists believe that severe climate change, for example more severe droughts or more intense heat, could significantly weaken the absorption capacity of terrestrial ecosystems.
Modeling the future of vegetation carbon uptake
However, in a recently published study, Knauer et al. present the results of a modeling study set up to assess high-emissions climate scenarios and how vegetation carbon uptake will contribute to global climate change by the end of the 21st century. We are testing whether it responds tocent century.
The authors tested different versions of the model, varying in complexity and realism, for how physiological processes in plants are explained. The simplest version ignored his three important physiological mechanisms related to photosynthesis, while the most complex version explained all three of his mechanisms.
The results were clear. More complex models that incorporate more current plant physiological understanding consistently predicted stronger increases in vegetation carbon uptake globally. The described processes are mutually reinforcing, so their effects are even stronger when described in combination. This is what happens in real-life scenarios.
Implications for climate change strategy
Sylvia Caldaral, assistant professor in Trinity’s School of Natural Sciences, was involved in the research. Contextualizing the findings and their relevance, she said:
“The majority of terrestrial biosphere models used to assess global carbon sinks are at the lower end of this complexity range, and either only partially account for these mechanisms or By ignoring it completely, we may currently be underestimating the effects of climate change on vegetation, as well as their resilience to changes in climate. We believe that climate models are all about physics. It’s easy to think, but biology plays a big role and you really need to take that into consideration.
“These kinds of predictions have implications for nature-based climate change solutions such as reforestation and tree planting, and how much carbon such efforts can sequester. It suggests that the approach could have a greater long-term impact in mitigating climate change than we thought.
“But simply planting trees won’t solve all our problems. We absolutely need to reduce emissions from every sector. Trees alone offer humanity a get-out-of-jail-free card. You cannot.”
Reference: “Increasing global gross primary productivity in future climates through a more advanced expression of photosynthesis” Jürgen Knauer, Matthias Cuntz, Benjamin Smith, Josep G. Canadell, Belinda E. Medlyn, Alison C. Bennett, By Silvia Caldararu, Vanessa Haverd, 17 November 2023 scientific progress.
DOI: 10.1126/sciadv.adh9444