Soil biological activities

CCP3 Soil biological activity and structural stability... 

Yeates, G.W., V.A. Orchard, T.W. Speir, J.L. Hunt, andM.C.C. Hermans. 1994. Impact of pasture contamination by copper, chromium, arsenic timber preservative on soil biological activity. Biol. Fertil. Soils 18 200-208. 

The percentage of the CEC occupied by specific cations influences soil pH and associated characteristics relevant to plant growth and soil biological activity. Only the most strongly held cations remain in soils in high rainfall areas. Al dominates the CEC, hydrolyzing when released from the solid phase to the soil solution to form acidic soils with pH values often below 5. 

An ecological production management system that promotes and enhances biodiversity, biological cycles and soil biological activity. It is based on minimal use of off-farm inputs and on management practices that restore, maintain and enhance ecological harmony. 

Individual enzymes or classes of enzymes in soils have been assayed under a variety of conditions, thus limiting the scope for comparing activities reported from different laboratories. Galstyan recently has described assays for five enzymes considered important for assessment of soil biological activity and has called for a standardization of methods. Roberge and Burns have reviewed aspects of methodology regarding pH control, choice of buffer if any, duration of assay, substrate concentration, and soil sterilization. 

---