There are currently 450 petagrams (1 petagram = 1,000,000,000,000 kilograms) of carbon in plants on Earth. Without humans, there would be 916 petagrams of carbon stored in plants; humans are responsible for reducing this biomass by over 50%.

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There are currently 450 petagrams (1 petagram = 1,000,000,000,000 kilograms) of carbon in plants on Earth. Without humans, there would be 916 petagrams of carbon stored in plants; humans are responsible for reducing this biomass by over 50%.