Non-symbiotic nitrogen-fixing organisms in Queensland soils

Abstract

The occurrence of Azotobacter chroococcum and Clostridium spp. has been determined in a number of cultivated and virgin Queensland soils, representing a wide range in soil characteristics. There was no indication that Azotobacter occurred more frequently in virgin than in cultivated soils. Anaerobic species of Clostridium were found constantly in Queensland soils.