Reposted from In.gredients.com
By Lauren Welker
Nitrogen (N2) is an essential nutrient for all living organisms, and it’s one of the most important nutrients needed for plant growth. Without it, plants are unable to produce complex organic molecules like amino acids, proteins, and nucleic acids. For something that comprises 78% of the Earth’s atmosphere – and is so critical to living organisms – one would think plants and animals wouldn’t have a problem obtaining nitrogen. However, it turns out life can only absorb nitrogen once it’s “fixed” – meaning, confusingly, “broken apart” – and bonded to another element.
It’s almost miraculous that we have life at all on Earth, because nitrogen fixation can only occur two ways: lightning and bacteria. The energy from the lightning has the ability to rip N2 apart, allowing the freed nitrogen to bond to oxygen molecules and form NO3- (nitrate) which then rains down on plant life.
Particular types of bacteria in the soil can fixate nitrogen via respiration (energy production). One of the easiest ways farmers facilitate this process is by planting legumes, which have a special symbiotic relationship with the bacteria Rhizobium. Tiny microorganisms can do the same thing as lightning – how cool is that?
The nitrogen absorbed by the plants is passed through the food chain to animal life, and then put back into the soil and atmosphere through animal waste and the decomposition of plant and animal matter – this is totally that Circle of Life Mufasa was talking about.