Research On The Degradative Ability Of Plants To Oily Soil In Daqing

Daqing oil field is the biggest one in China, as well as 20ed in the world. In the process of petroleum producing, store transporting, refine processing and using, because of the reasons of accident, not normal operation and overhaul and so on, there will have petroleum hydrocarbon spilling over and emission. Due to the features of invisibility, chronicity and irreversibility in soil, the traditional physical and chemical methods may result in both the destruction of soil structure and deterioration of chemical fertilizer and the costly administration and expensive investment. Meanwhile it is difficult to deal with the pollution in large scale. Technology of plant ecological restoration, however, can recover the disadvantage of traditional management and it is beneficial for environment. It costs less but can be operated easily with fewer disturbances to the environment, and at the same time it absorbs the organic pollutants from soil and can eliminate those harmful substances from atmosphere nearby and water. It can be accepted by the society due to the high value of beautifying environment. Therefore the fundamental theory of technology of plant ecological restoration has been a hot topic in international academic research in this field.Phytoremediation were studied under different oil concentration in pot experiments. The tested soils were meadow soil, chernozem, saline-alkaline soil, sandy soil and mire soil. The tested plants were alfalfa, artemisia scoparia, chenopodium album L, chloris virgata, leymus chinensis, serratula yamatsutana kitag, elymus nutans, puccinellia tenuiflora, stipa species, salsola collina pall, artemisia frigida and reed. The experimental duration was 60d and the soil samples were collected every 10d to evaluate pH value, electrical conductivity, oil content, organic content, catalase content, free and pyrogenic organic content. The results are as follws.1. The degradative ability of leymus chinensis, salsola collina pall, alfalfa, reed and stipa species were good respectively in the soil of chernozem, saline-alkaline soil, meadow soil, mire soil and sandy soil. Leymus chinensis and salsola collina pall had high degradation in the low oil-contaminated soil (oil content was 2.19g/kg). Artemisia scoparia had high degradation in the moderate oil-contaminated soil (oil content was 3.66g/kg). Reed and alfalfa had high degradation in the high oil-contaminated soil (oil content was 4.94g/kg).2. The soil samples were measured and analyzed regularly and found influence factors had certain regularity with the change of time. The changing of pH value and electrical conductivity resembled sinusoid and decreased gradually. The content of oil and organic reduced slowly too. But catalase content is higher than initial value.3. The article gave the correlation analysis to the influence factors. There was certain correlation between organic content and degradation degree, catalase content and pH value, pH value and electrical conductivity, organic content and catalase content.