Are some plants better than others at sucking up carbon dioxide?

Asked by: Roy Musselbrook, Ramsgate

Plants use carbon dioxide (CO₂) during photosynthesis to make glucose. It takes six molecules of CO₂ to make every molecule of glucose, and this basic building block is then used for energy and to make the structure of the plant itself. This biochemical reaction is the same for all plants, but the faster a plant grows, the more carbon dioxide it will use up per second. By that measure, bamboo might be the best at sucking up CO₂. However, fast-growing plants tend not to live long and when a plant dies, all the carbon in the plant is broken down by insects, fungi and microbes and released as CO₂ again.

So the plants that are considered the most adept at locking away carbon dioxide from the atmosphere are the longest-living ones, with the most mass – hardwood trees. It’s all temporary though. Eventually every plant returns all the carbon dioxide it uses back to the atmosphere.

Read more:

• Could captured carbon dioxide be stored in the deep ocean?
• Could an intelligent species evolve on Earth that breathes carbon dioxide?

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