Zafarjon Jabbarov, Tokhtasin Abdrakhmanov, Alim Pulatov, Peter Kováčik and Khabibullo Pirmatov
The oil well drilling and oil processing industries are globally the main contaminants of environmental condition caused by human economic activities. Oil spills have a negative impact on the environment, economy, and society. In this research, the effects of oil with different chemical contents on soil types formed in two soil-climatic conditions have been studied. The purpose of this research is to study the change of soil properties by oil pollution. The experiments have been conducted in irrigated and non-irrigated soils of the desert region of the Kashkadarya and Surkhandarya (Uzbekistan). The results have shown that aggregates (0.25; 0.5; 1; 2; 3; 5; 7; 10 mm) which are the important of soil fertility have changed by oil and oil production, and the changes have proven to be temporary. The effect of the 5% and 15% concentrations of oil, engine oil, petrol, kerosene has been studied. The aggregates 0.25 mm and 0.5 mm have the biggest change among aggregates, in fact, aggregates of 0.25 mm at the level of 5% of oil decreased by 27.02%, at the level of 15% of oil decreased by 99.8%, at the level of 5% of kerosene decreased by 2%, at the level of 15% of oil decreased by 98.1%. Aggregates of 0.5 mm at the level of 5% of oil decreased by 6.44%, at the level of 15% of oil decreased by 67.14%, at the level of 5% of kerosene decreased by 12.75%, at the level of 15% of oil decreased by 92.8%. Engine oil and Petrol at levels 5 and 15 have relatively rare changed. Also, as a result of oil and oil pollution, the total carbon dioxide in the soil has grown briefly, which is an anthropogenic carbon and insignificant for soil fertility and humus. As a result, an anthropogenic carbon increased in gray-brown soil (Durisols Technic, WRB) at 0 – 35 cm layer by 0.22%, irrigated meadow-alluvial soil (Fluvisols, WRB) by 0.31%, irrigated gray-brown soil (Durisols Technic, WRB) by 0.44%, irrigated Takyr-meadow soil (Calsisols, WRB) by 0.25%, Takyr soil (Calsisols, WRB) by 0.32%, sandy Desert soil (Durisols Technic, WRB) by 0.21%.