Soil microbial biomass C (Cmic) estimate by the chloroform-fumigation-extraction method described by Brookes et al. (1985) and Vance et al. (1987). Cmic was calculated from the difference in extractable organic C between fumigated and unfumigated soil samples as follows: biomass C = 2.64 EC, where EC refers to the difference in extractable organic C between the
fumigated and unfumigated treatments; 2.64 is the proportionality factor for biomass C released by fumigation extraction. But I cant find for water samples?