Nitrogen fixing plants are key constituents in many natural ecosystems in the world.
They are the major source of all nitrogen that enters the nitrogen cycle in these ecosystems. In temperate areas, the nitrogen fixers tend to be herbaceous. NFTs have been removed or reduced in most man-made ecosystems, such as agricultural and forest lands and urban environments. These lands require expensive chemical fertilizer inputs in order to maintain their productivity. Manmade systems can be improved by learning and adopting from natural ecosystems.