How the excessive use of fertilizers affects the nitrogen cycle

When farmers harvest crops, a lot of the plant material is also removed. Little is left to decay and return nitrogen to the soil. If the soil stays this way, it will start producing fewer crops. Fertilizer contains the nitrogen compounds that are essential for plant growth. It can be used to replace the nitrogen in the soil to ensure the growth of healthy crops.

In natural conditions, plant growth is limited in many places by the amount of usable nitrogen that is available in the soil. To grow more crops, people have been transforming nitrogen from the atmosphere into nitrogen fertilizers and then adding the fertilizers to the plants.