 "Betaproteobacteria" are economically important, with roles in maintaining soil pH and in elementary cycling.Other economically important members of the "Betaproteobacteria" are able to use nitrate as their terminal electron acceptor and can be used industrially to remove nitrate from wastewater by denitrification.A number of "Betaproteobacteria" are diazotrophs, meaning that they can fix molecular nitrogen from the air as their nitrogen source for growth - this is important to the farming industry as it is a primary means of ammonium levels in soils rising without the presence of leguminous plants.