TORONTO -- Human activity has significantly increased the amount of carbon dioxide in Earth's atmosphere – and new research suggests that trees are working harder than ever to try and mitigate it.

Researchers in the United Kingdom sprayed carbon dioxide into a mature oak forest three years in a row, to see how the trees would react.

They found that the trees increased their photosynthesis activity – the process that converts the harmful greenhouse gas into oxygen – by 33 per cent. In other words, the trees were able to adapt to the newly CO2-rich atmosphere and do more to clean it up.

However, as CTV News Science and Technology Specialist Dan Riskin explains in this week's Riskin Report, the trees' mighty efforts aren't enough on their own to counteract the real increase in CO2 emissions caused by humans.

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