THE SYRT-VOLGA REGION CHERNOZEM RECLAMATION DISTURBED BY OIL PRODUCTION
The aim of the research is to develop means of reclamation of oil-contaminated and solinification for its involvement into agricultural crop rotation. Oil and produced water are typical and spread pollutants of the field where production is being developted. Szik soil and oil polluted areas were marked at the production fields and agrochemical analysis of their condition was carried out resulted from soil-reclamation survey made during 2012. The content of sodium ions Na+, chlorine Cl-, carbonate anions CO32- , on the basis of which the degree of salinization of soils, and types of salinization - chloride, chloride-soda, soda, soda-sulfate was estimated. During the field operation period increase in the degree of salinity from weak to very strong was tested. The dynamic of agrochemical indicators of soil cover was determined. The humus content is 3.10-4.71 %, the pH of the soil solution varies from close to neutral to slightly alkaline (pH 6,2-8,3), soil labile phosphorus - from very low to very high (4.4-217.9 mg/kg), potassium - from very low to high (63.0-665.0 mg/kg). It is established that oil products in the upper soil horizon are found locally, reach the category of high level of pollution and require special measures for reclamation. A slight increase in regard to adopted measure in local areas is observed at a depth of 20-40 cm and 40-60 cm, it is within the limits possible for soil self-purification. Names for soil varieties were clarified. On the soil parts with a total area of 63.8 hectares, the saline land was 30.02 hectares, disturbed soils - 17.65 hectares, contaminated with oil products - 5.3 hectares, soil covering area of 24.49 hectares remained not polluted (can be returned to the crop rotation). For recultivated soil, the calculation of the need and application rates was performed: gypsum - 74.31 t, mineral fertilizers - 347.08 C, organic fertilizers - 12455 t.