Nitrogen Mineralization from Organic Amendments

By Ben Faber

Daniel Geisseler, Professor of Nutrient Management at UC Davis has developed a tool for estimating the mineralization of nitrate-N from organic amendments. How much and when nitrate-nitrogen becomes available from organic amendments and fertilizers is difficult to know precisely. This tool provides estimates of mineralization of six materials. Soil temperature and moisture are critical drivers in mineralization of materials of specific carbon to nitrogen ratios. The tool provides mineralization estimates based on soil temperature data from local CIMIS weather stations, and soil moisture is assumed to be optimal near field capacity, as is the case in production fields with growing crops. The tool has an option to select rates of mineralization from different areas in the State. This tool will provide useful estimates for growers and crop consultants making decisions regarding nitrogen contributions from selected organic amendments to crops. Here is the link to the tool:

http://geisseler.ucdavis.edu/Amendment_Calculator.html