Investigation of the Impact of Historic Biosolids Applications on Soil Microbial Activity
ISBN: 1 84057 624 3
This project measured soil microbial properties at sites which had a history of operational biosolids additions in comparison with nearby 'control' fields. It found no statistical differences in soil microbial biomass (a measure of the size of the microbial community) levels between the fields receiving biosolids appications and the 'control' fields, and very few relationships between biomass size and soil heavy metal concentrations. Clover Rhizobium numbers were statistically lower (around 1log10) in the biosolids treated fields than in the 'control' fields, with some inverse relationships between Rhizobium numbers and soil heavy metal concentrations. However, Rhizobium were present in all of the 38 fields sampled to support clover inoculation and growth.