Nitrogen pollution removal from areas of intensive farming—comparison of various denitrification biotechnologies

In recent decades, dynamic demographic processes resulting in an increased intensity of agricultural food production have changed the natural flow of nitrogen (N2). This modification of the nitrogen cycle has led to number of changes. As nitrate is the most mobile form of nitrogen in soil, it is the most dangerous polluter of waters, and causes many diseases, including methaemoglobinaemia. Nitrogen contributes to the eutrophication of freshwater and marine ecosystems, resulting in the intensive development of toxic algal blooms and, often, the exclusion of affected freshwater from drinking water resources.A literature review indicates that applying various biotechnologies to the denitrification process reduces the nitrogen load on the catchment scale by up to one order of magnitude, and seems to be an inexpensive tool for the reduction of nitrate loads to surface waters. Various reports underline the role of abiotic factors dependent on the climate, geology and management of agricultural areas. Depending on the specificity of a nitrogen pollution source, different biotechnological solutions can be applied in the field. For example, in a catchment with intensive farming or pasturing, around a point source such as manure storage, or near the coastline, denitrification walls can be an appropriate solution.Protection and restoration should employ methods used for gradually developing the properties of the ecosystem responsible for its resilience and ability to respond flexibly to human pressure. These treatments are designed to restore the biogeochemical cycles of evolution-shaped properties and increase the resilience of the environment to human pressure.