APPENDIX 341 



V. SOIL 



A. The Making of Soil. 



1. Microorganisms in soil. 



a. Number at different depths and in different 



soils. 



b. Kinds at different depths and in different soils. 



c. Character of microorganisms found. 



d. Rate of growth. 



2. Disintegration of inorganic material. 



3. Decomposition of organic material. 



a. Celluloses. 



6. Starches and sugars. 



c. Proteins, etc. 



4. Action of iron and sulphur bacteria. 



B. Ammonification. 



C. Nitrification The nitroso- and nitro-processes. 



1. Conditions influencing. 



a. Physical. 



b. Reaction. 



c. Temperature. 



d. Supply of oxygen. 



e. Amount of organic matter present. 

 /. Moisture. 



D. Denitrification. 



1. Factors influencing the loss of nitrogen. 



E. Nitrogen Fixation. 



1. Symbiotic. 



2. Nonsymbiotic (aerobic and anaerobic). 



