For instance, nitrogen—which comes from fertilizers—in the form of nitrous oxide is a greenhouse gas 300 times more potent than carbon dioxide.I'm no chemist but nitrogen, if I remember, is about 80 percent of the atmosphere. And "nitrogen" fertilizer is not nitrogen, but nitrates (that's why it takes energy to make chemical fertilizer). Wikipedia may be reliable,, or not:
Nitrous oxide is emitted by bacteria in soils and oceans, and thus has been a part of Earth's atmosphere for eons. Agriculture is the main source of human-produced nitrous oxide: cultivating soil, the use of nitrogen fertilizers, and animal waste handling can all stimulate naturally occurring bacteria to produce more nitrous oxide. The livestock sector (primarily cows, chickens, and pigs) produces 65% of human-related nitrous oxide.  Industrial sources make up only about 20% of all anthropogenic sources, and include the production of nylon and nitric acid, and the burning of fossil fuel in internal combustion engines. Human activity is thought to account for somewhat less than 2 teragrams of nitrogen oxides per year, nature for over 15 teragrams.If I understand, chemical "nitrogen" fertilizers are mostly anhydrous ammonia, ammonia nitrate, and urea.