PLANTS

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Carbon Dioxide: Pollutant Or Plant Food?

Life evolved to live within limits. It's a delicate balance. Humans need oxygen, but too much can kill us. Plants need nitrogen, but excess nitrogen harms them, and pollutes rivers, lakes and oceans. Ecosystems are complex. Our health and survival depend on intricate interactions that ensure we get the right amounts of clean air, water, food from productive soils and energy from the sun.