Roslyn Gleadow, a biologist at Monash University in Australia who studies nitrogen metabolism in plants and didn’t contribute to the review, notes that the hypotheses that high carbon dioxide alters ...

However, although our atmosphere contains plenty of nitrogen, neither humans nor the vast majority of plants can absorb ... microbes use nitrogen in their metabolism, they use these two isotopes ...

Here's our guide to feeding your garden. Most plants need three major nutrients to thrive; nitrogen, phosphorous and potassium, which are generally known as NPK (their chemical symbols).