Professor Yakir explains that because of the rise in the level...

Professor Yakir explains that because of the rise in the level of carbon dioxide in the air, the trees absorb all the carbon dioxide they require without needing to fully open all the stomas (apertures) in their leaves' membranes. Partial opening of the stomas reduces the evaporation of the water on the leaves and so a tree uses less water without any damage to its development.

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