Unsung and infamous: Fritz Haber inventor of the nitrogen-fixation process (later industrialized by Carl Bosch, which is why it is known as the Haber-Bosch proc

Unsung and infamous: Fritz Haber inventor of the nitrogen-fixation process (later industrialized by Carl Bosch, which is why it is known as the Haber-Bosch process.) At a minimum, 3 billion people are alive today because the proteins in their bodies contain nitrogen that had been fixed by fertilizers created in factories using this process. Without artificial fertilizers produced with this process it would be impossible to support a human population of more than 4 billion people even if every bit of arable land were being farmed to maximum capacity. The Haber-Bosch process broke through the hard limit of how much plant protein could be produced through agriculture and led directly to the population explosion started in the 19th century. Paraphrasing Vaclav Smil's arguments: Naturally-produced fertilizers can provide approximately 200 kg. of nitrogen per hectare annually; this allows for the production of between 200 and 250 kg. of plant proteins. This places a theoretical limit on the number of people that each hectare of land could sustain. Under ideal conditions this would amount to around 15 people per hectare; in practice, the historical limit has been about 5 people per hectare. Note: he also invented chlorine gas for use during World War I