ABSTRACT

Components and processes to be measured includes mycorrhiza, nitrogen fixation, biomass production, mineralization-immobilization, nitrification, denitrification, organic matter, available phosphorus and other nutrients, soil Carbon dioxide (CO2) and O2, and soil structure. The postulated doubling of atmospheric CO2 is not likely to have a direct effect on soil microbial activity because during the growing season, the concentration of CO2 in the soil atmosphere is already ten to fifty times higher than existing atmospheric CO2. The biogeochemical cycle of carbon which integrates aerial, soil, and aquatic activities constitutes the basic mechanism for the production of renewable resources such as food, fiber, and fuel, and for the removal of organic detritus through mineralization. At first glance, bacterial and cyanobacterial photosynthesis may not loom as large in cultivated and non-cultivated ecosystems as green plant photosynthesis, but the contributions of microbes to carbon fixation cannot be ignored.