Measurement of phosphorus in the soil microbial biomass:A modified procedure for field soils

摘要: Abstract A range of gaseous, liquid and vapour biocides was tested in combination with seven extradants for their ability to release P from soil microorganisms situ . The were chloroform, ethanol, propan-1-ol, hexan-1-ol, β-propiolactone, formaldehyde, glutaraldehyde, ethylene oxide methyl bromide. 0.5 M NaHCO 3 (pH 8.5), 0.1 50 mM NaOH, 10 CaCl 2 , m H SO 4 30 NH F + HC1, an anion exchange resin the bicarbonate form suspended distilled water. An incubation technique using 32 ensured that only microbial measured. Chloroform hexanol most effective biocides: latter is preferred because its less hazardous nature. best extradant 8.5). Mixed populations organisms used calibration, K p factors obtained 8.5) 0.33, 0.40 0.57 three soils studied. Since microflora differ soil, as do amounts released, calibration necessary each soil. Incubation not recommended a prior treatment samples measure biomass P: should be treated or extracted immediately after sampling avoid quantitative qualitative changes biota biomass. Errors associated inclusion roots sample can minimized by removing bulk before fumigation.