Effluents from the Mathura oil refinery have been causing severe water pollution and soil contamination in the surrounding areas. Soil contamination by the effluents showed undesirable physico-chemical and microbiological characteristics. In the present study, rice husk, the naturally available organic material has been mixed (in composted form) in varying concentrations, viz., 5%, 10%, 15%, 20% and 25% dosages (w/w) with the oil refinery effluent contaminated soil of Mathura to assess its efficacy in restoration of the health status of the soil. Different physico-chemical characteristics showed a definite change in values, with increasing concentrations of rice husk compost. The values of pH, moisture content, water holding capacity, organic carbon, organic matter, total nitrogen, available phosphate and exchangeable potassium increased in soil enriched by rice husk, showing its positive role in management of soil contaminated by effluents from the oil refinery. Microbial counts (fungal, bacterial and actinomycetes) revealed an increasing trend with increase of rice husk concentration, which might be attributed to improved soil physico-chemical attributes. Qualitatively, soil microfungi expressed different dominant community members in different doses of enrichments, as revealed from the data of IVI (important value index) of individual fungal species.

The present work entailed collection of soil samples from fields irrigated with the oil refinery effluent. The soil samples were collected up to 0 to 6 cm depth from the surface with the help of sterilized iron borer during the month of May 2006. The soil samples were brought to the laboratory for isolation of microflora and making an analysis of physico-chemical properties of soils as per standard methods adopted by Jackson (1973), and Piper (1967). To evaluate the role of organic enrichment on physico-chemical and microbiological attributes of the soil contaminated by effluent from the oil refinery, rice husk (composted organic material) was used.

Freshly collected, air-dried and sieved soil samples weighed in equal amounts, were taken in separate fresh polythene bags. To each bag the enricher was mixed separately in the ratios of 5%, 10%, 15%, 20% and 25% (w/w) respectively. The moisture status of the amended soil samples was maintained at 60%-70%. The samples were stored at room temperature and detailed analysis was made after 10 days of amendment. Natural soil samples without any amendment to serve as control were also similarly maintained and studied.

Management of Oil Refinery Effluent Contaminated Soil Using Composted Rice Husk, rice husk compost, physico-chemical and microbiological characteristics, soil contaminated, air-dried and sieved soil samples, organic enrichment, Microbial counts, bacterial and actinomycetes.