Lotus corniculatus crop growth in crude oil polluted soil. Part 1 total petroleum hydrocarbons reduction of polluted and cultivated soil

Abstract

The use of power plant fly ash, by its physical-chemical properties, can significantly change the characteristics of soils polluted with oil (Total Petroleum Hydrocarbons, TPH), in their rehabilitation process, if combined with biodegradable organic materials, wastes such as sewage sludge from municipal wastewater treatment plant. Maintaining vegetation on soils polluted with 80.5±3.9 g·kg-1 D.M. of TPH under perennial regime specific to bird’s foot trefoil (Lotus corniculatus), demonstrates the tolerance of the plant to the created conditions by the treatment of polluted soil with adequate amounts of fertilizer and fly ash from burning coal in power stations. The addition of 50-500 g fly ash per vegetation pot equipped with crude oil polluted soil mixed with 250 g sewage sludge per pot has reduced the oil content in the soil, in two ways: on the one hand influenced by the state of development of plants and on the other hand by weather conditions (alternation of seasons). The amount of TPH lost during the 16 months of vegetation in soils polluted with 80.5±3.9 g·kg-1 D.M. was 73.3-77.5 g·kg-1 D.M.