Many of my friends ask me why is nitrogen fixation necessary for plants and for life on Earth as we know it. The short take is that no plant on Earth can grow with out the N that this swap gives the soil. Your air has lots of N gas in it. But the gas is locked in a form that no plant can use as food.
The full importance of nitrogen fixation hits home when you grasp how much you rely on it. Each meal you eat has N in it. That N came from the air just days or weeks back. The swap from gas to food is what put the N in your bread and your beans.
I had a sharp wake-up call to this fact on a trip to a wheat farm in Kansas. The farmer told me his crop would yield zero pounds if no swap from gas to feed took place. That blew my mind since the air over his fields was so full of N gas.
The gap is the form of the N. N2 in your air has a tight bond that plants cannot crack. Plants need N as NH3 or NO3 to soak up through their roots. The swap from N2 to those soft forms is the whole point of this big topic.
Your plants use N to build the parts that keep them alive. The list is long and key. N goes into DNA. N goes into the green stuff in leaves. N goes into the proteins that hold each cell up. With out N, your plants would not have any of these parts.
When I see pale yellow leaves on my crops, I know the soil fertility is low. The plants are telling me they need more N. I have learned to spot this sign in just a few days. It saves me from huge crop loss each year in my home plots.
The need for nitrogen for plants is the same in your beds, in fields, and in wild lands. A bean plant in your yard needs it. A wheat field in Kansas needs it. A tree in a deep wood needs it. All life on land draws on the same swap from gas to food.
Bugs in soil do the bulk of this swap for free. They give us about 122 million tons of N each year through this work. This huge gift feeds about half of the folks on Earth through bean crops and the wild lands that hold N in their soil.
I have done my own tests to see this gift in action. In one bed, I grew peas one year and then corn the next. In a side bed, I grew corn both years. The bed with the pea cover out-grew the plain bed by 40% in the second year.
The other half of our food comes from human-made feed in big bags at the store. We make those bags by the same swap, but in big plants we built. With out both routes, the world would have a huge gap in food security within just one year.
Think for a sec how big this is. The swap from N2 to food is what lets us feed eight billion folks on this small planet. No other swap or trick that we know of can fill the same role. So we have to keep this swap going at full speed each day.
You can help in your own yard with a few easy moves. Plant beans, peas, or clover in your beds each year. Use a cover crop in the off-season. Add a small bag of rhizobia coat when you plant new beans. These moves keep the bug team in your soil strong.
When folks ask me why is nitrogen fixation necessary, I now have a short and clear way to share the take. The short take is that all life on land relies on it for food each day. Without it, your plants would die, your crops would fail, and the food chain would break down fast. I have shared this with my own kids and they got it in less than five minutes. You can now see why this small swap is such a big deal.
Read the full article: Nitrogen Fixation: How Bacteria Feed the World
