Biology and Fertility of Soils

, Volume 39, Issue 6, pp 446–451

Determination of soil microbial biomass phosphorus in acid red soils from southern China

Original Paper

DOI: 10.1007/s00374-004-0734-6

Cite this article as:
Chen, GC. & He, ZL. Biol Fertil Soils (2004) 39: 446. doi:10.1007/s00374-004-0734-6


A CHCl3 fumigation and 0.03 M NH4F-0.025 M HCl extraction procedure was used to measure microbial biomass P (Pmic) in 11 acid red soils (pH <6.0) from southern China and the results compared to those obtained by the commonly-used CHCl3 fumigation and 0.5 M NaHCO3 extraction method. Extraction with NH4F-HCl was found to be more effective and accurate than NaHCO3 extraction for detecting the increase of P from microbial biomass P following chloroform fumigation due to its higher efficiency in extracting both native labile phosphate and added phosphate (32P) in the soils. This was confirmed by the recovery of 32P from in situ 32P-labeled soil microbial biomass following fumigation and extraction by the NH4F-HCl solution. Soil microbial biomass P, measured by the NH4F-HCl extraction method, was more comparable with soil microbial biomass C (with a more narrow C:P ratio range of 4.3 to 22.3 and a mean of 15.6 in the microbial biomass), than that obtained by NaHCO3 solution (with a mean C:P ratio of 30.7 and a wide range of 14.9 to 48.9). Kp, the fraction of soil microbial biomass P extracted after CHCl3 fumigation, by the NH4F-HCl solution was 0.34. The amount of microbial biomass P determined (using Kp =0.34) was 3–400% (mean 131%) higher than that obtained by the NaHCO3 extraction (using Kp =0.40) for the 11 red soils studied. The results suggest that the CHCl3 fumigation and NH4F-HCl extraction method is more reliable for measuring microbial biomass P than the NaHCO3 extraction method in acid red soils.


Fumigation-extraction methodMicrobial biomass phosphorusAcid red soils

Copyright information

© Springer-Verlag 2004

Authors and Affiliations

  1. 1.Department of Natural Resource Science, College of Environmental and Resource Sciences, Huajiachi CampusZhejiang UniversityHangzhouChina
  2. 2.Indian River Research and Education Center, IFASUniversity of FloridaFort PierceUSA
  3. 3.University of Florida-IFASIndian River Research and Education CenterFort PierceUSA