REDUCTION PROCESSES IN THE SOIL 557 



diminution of the reduction of phosphate, since the activities of the 

 reducing microorganisms were directed towards the more readily reduca- 

 ble compounds. Carbon compounds were used as sources of energy: 



2 H3PO4 + C = 2 H3PO3 + C0 2 

 2 H3PO3 + C = H3PO2 + C0 2 

 H3PO2 + C = PH 3 + C0 2 



The reduction of various organic compounds in the soil, under anaerobic 

 conditions, is very common, as pointed out previously. 



