Mechanical, physico-chemical and microbial analysis of oil refinery waste receiving agricultural soil.

Abstract

The mechanical, physico-chemical characteristics of soil and the activity of indigenous microflora were studied in the agricultural soil steadily receiving petroleum refinery effluent at Mathura, U.P, India The data on the soil grain size and texture revealed that the soil in the test region was basically loam or silty loam. Physic-chemical analysis showed considerable variability in the soil pH, temperature, moisture content and water holding capacity (WHC). A substantially higher microbial activity was noticed at the test sites as evident from the total variable (10(5) to 10(9) CFU g-1 soil) bacterial population. In addition, a significant population of proteolytic and cellulolytic bacteria, rhizobium and actinomycetes was detected. Oligotrophs were isolated and characterized into four types (I-IV). A fraction of oligotrophic bacteria, particularly those belonging to type II and type IV exhibited appreciable in distilled water. Invariably higher microbial biomass ranging from 366 to 1604 mg CO2. 100 g-1 soil, clearly implied that the soil in the test region was very well nourished and the refinery waste was providing enough nitrites to support the growth of soil microflora.