Evaluation of organic carbon in fertilizers and amendments.

High amount of biomasses of agro-industrial and municipal origin can be properly transformed into organic compounds that can be used in agriculture as soil amendments, organic-based fertilisers, growing media and organic products with biostimulant activity. Amendments are particularly recommended in soils where the organic carbon content is very low (i.e. < 1.0%), i.e. in the Mediterranean soils, contributing to the natural closure of the nutrients cycle, to the increase in soil fertility and in carbon sink. A sustainable use of organic materials can be obtained only by a deep study of the quality of their organic and humified carbon. Up to date at European scale (EU at 27 Countries) the EC Reg. 2003/2003 only regulates mineral fertilizers, whereas organic, organic-based fertilizers and amendments are not included. This means that the control of organic-based fertilisers is devoted to each Member State and all the fertilisers made in the EU-27 can freely circulate from a country to another, abiding by the laws of the country of origin. In this respect the Italian law on fertilisers is advanced and many parameters have been settled in recent years. The paper reports some selected examples of official analytical methods used in Italy to characterize amendments, organic-based fertilisers, growing media and organic products with biostimulant activity recently settled by the Italian law of fertilisers (D.Lgs. 217/06).