Effects of experimental manipulation of environmental factors on phenol mineralization in soil

Abstract

The effects of temperature and nitrogen, phosphorus, and carbon enrichments on phenol mineralization were determined in the uppermost and deepest horizons of two contrasting soils. Soil samples were amended with trace levels of 14C-phenol and incubated under various experimental conditions. Mineralization was determined by measuring the production of 14CO2 with time. First-order rate constants (k) and extent of mineralization (PO) were estimated from the resulting data using nonlinear regression. Temperature affected mineralization differently as a function of soil type. While not stimulating mineralization in the upper horizons, nitrogen and phosphorus enrichment resulted in faster and more extensive mineralization in the subsurface horizons. Carbon (cellulose) enrichment had little effect in any soil examined. This study demonstrates the importance of temperature and inorganic nutrient availability in controlling the biodegradation of a model pollutant in surface and subsurface soil. It further illustrates the variability that exists between soil types and between different horizons of the same soil type as to factors capable of influencing biodegradation processes.