Envirill 



We also had some studies on the influence of temperature on the oxidation 

 of ammonia. Again, this was a practical problem, but, in all probability, 

 a large majority of the other microorganisms in the soil would react liko 

 the nitrifiers. In the last graph, Figure 11, is plotted the influence 

 of temperature on the rate of -oxidation of ammonia to nitrates in a nmi- 

 ber of soils. The influence varies between soils and is not v;ell defined. 

 In general, one can say that within the limits of the range of Eoil tem- 

 peratures (8° to 25° C.) there is a direct relationship betvroen soil 

 temperature and microbial activity. Other data support this thesis that 

 nearly complete inhibition of these activities does not result until the 

 temperature gets down to the freezing point. Again, this is the charac- 

 teristic of the microflora in general, the overall, not the specific, 

 members of the microflora. 



In conclusion, the data which have been presented are of the overall 

 activity of the gross microflora. The influence of the individual fac- 

 tors on specific members I do not know, nor would I know where to find 

 the information that would help out in that respect. I do presume that 

 various members of the soil micro-populations do act quite differently. 



