Nitrogen Fixation by and Isolation of Rhizobium Species from Native Legumes from a Tall Grass Prairie in South Dakota

This thesis is concerned primarily with the occurrence of nitrogen fixation in native legumes on burned vs. unburned sections of the tall grass prairie. It is also concerned with the isolation of the root nodule bacteria and their identification as rhizobia. Various other biological data such as plate counts a of soil bacteria and azotobacter plate counts along with the influence of abiotic factors such as temperature, soil moisture and organic matter were determined to see in a relationship could be detected with nitrogen fixation.