dS 

 dt 



^r= D(S,-S) - k,SH - k 3 SP 



dH 

 dt 



dP 

 dt 



= k,SH - DH - k.HP 



k HP + k SP - DP 



5 6 



M3) 



Here the term k SP is the consumption of DOM by zoof lagellates and k 6 SP is 

 their growth (per unit time) due to DOM consumption. 



The mathematical models (1) - (3) are not applicable for experiments 

 with nitrogen deficiency, since in this case, the concentration of organic 

 matter is not the factor limiting the growth of bacteria. A system of equa- 

 tions which consider the role of nitrogen as the limiting factor has been 

 made up. 



For the system--organic matter-bacteria: 



dN 

 dt 



dH 

 dt 



dS 



= D(Nj-N) - kjNH 

 = k„NH - DH 



M4) 



iji= D(S X -S) - k 3 NH 



For the system--organic-matter-bacteria-protozoa: 



dN 



dt 



dH 

 dt 



dP 

 dt 



D(Nj-N) - kjNH + k^P 



k 2 NH - DH - k 5 HP 



k 6 PH - DP 



dS 

 dt 



5|-= D(S r S) - k 3 NH 



M5) 



where N is the concentration of nitrogen in the inflowing medium, N is the 

 concentration of nitrogen in the reactor, and the remaining designations 



136 



