Fernández-Gómez et al. (2010) have reported
96% increased in nitrogen content after vermicomposting of
wastes. It might be due to the concentration effect caused by the
degradation of the labile organic compounds, which could have reduced
the volume of the composting mass due to release of CO2
and the mineralization of nitrogen during decomposition of organic
matter resulting in increased Ntotal in the vermicompost (Elvira
et al., 1998; Garg and Kaushik, 2005).