Nitrogen is a plentiful element in the biosphere, accounting for 78 percent of the air around us. It is essential for life, being a building block for proteins that all organisms need. The Romans recognized the need for nitrogen indirectly by noticing that grain crops produced greater yield when planted after certain crops, like lupin, that we now know to be legumes. German chemist Justus von Liebig identified nitrogen as a key mineral element for plant growth in the late 1800s. And the Green Revolution of the 1960s relied heavily on nitrogen fertilization of soils and crop varieties that could […]