Influence of different organic materials on the microbial biomass in contaminated soil of northeastern England

The microbial responses were studied in contaminated soil which was polluted by industrial wastes. By mixing the soil with the farmland soil in the ratio of 25% to 75%, different organic materials were amended to the mixed soil. During more than 70 days incubation, biomass C, P and available P were measured as an index for microbial influences by these materials in the contaminated soil. The results could be concluded as follows: Biomass C was greatly influenced by glucose and rape leaves, followed by farmyard manure and barley straw; Biomass P was significantly affected by rape leaves, followed by farmyard manure and barley straw; but the peak of which was later than that of farmyard manure; Available P of the control soil had the highest value compared with other amendments, among which glucose was the lowest one during the incubation time mainly because of the immobilization of available P by microorganisms.