DIN EN ISO 14238:2014-03

Soil consists of both living and non-living components which exist in a complex and heterogeneous environment. Microorganisms in the soil are mainly responsible for cycling of some nutrients and thus play an essential role in the maintenance of soil fertility. One of the most important microbial processes in soil is the mineralization of nitrogen contained in organic forms to ammonium (ammonification) and thereafter to nitrite and nitrate (nitrification). Clearly, any long-term interference with this process can influence soil fertility. This International Standard specifies laboratory procedures for measuring the mineralization and nitrification of nitrogen by the soil microbiota. For investigations on the evaluation of soil quality or on effects of contamination, a procedure is given to measure the rates and extent of N-mineralization in soil or soils of known or unknown quality. For investigation of the potential toxicity of chemicals to N-mineralization in soils, a simple procedure is given which allows the impact of single chemicals to be assessed and provides a basis for comparison of the toxicities of different chemicals. The committee responsible for this standard is NA 119-01-02-04 UA "Biologische Verfahren" ("Biological methods") at DIN.