Modelling of the number of hydrocarbonoassimilating bacteria and the control of biodegradation of oil in the soil
The faculty of natural sciences, Ufa State Aviation Technical University #12, Karl Marx Street, Ufa 450000, Russia
1Bashkir State University, faculty of biology, department of biochemistry and biotechnology # 32, Frunze Street, Ufa 450074, Russia
While modeling biological processes in oil contaminated soils, the following system of differential equations is used:
where С – is concentration of pollutant ; М – concentration of biomass of bacteria; t – time;
x –direction of the axis of diffusion; D – coefficients of diffusion of the pollutant and bio-mass. From the biological point of view, it is important to investigate the following kind of functions J1(M, C) and J2(M, C), that determine the behavior of the system under the estab-lished diffusion processes. Finding those functions , i.e. when a group of hydrocarbonoassimi-lating bacteria is viewed as microorganisms, helps to forcast and control the processes of oil biodegradation when entering biochemicals, that contain hydrocarbonoassimilating bacteria. When М0 – the number of bacteria at the starting point of time is supposed to be the capac-ity of the environment аnd - contamination level, that defines the negative influence upon the group of hydrocarbonodigesting bacteria, the following was chosen as functions:
J1(M, C) = ,
J2(M, C) = .
Thus, the С1(t), С2(t ) are the particles of the oil, that decompose under the influnce of biological and physico-chemical factors of the soil in the following way: . The calculations showed a good agreement with the model of the resultant experimental data during the first year after contamination. The analisis shows, that the model built that way, adequately describes the processes in soil and during long – time contamination. Entering the biochemicals will lead to the appearance of another item in the function J2(M, C).