Soil microbes working for nutrient dynamics and global environments

Soil microbes are playing important roles for nutrient cycling in terrestrial ecosystem and impacts on global environments. Soil microbial biomass works as driving force for dynamics of plant nutrients in crop production. Chloroform-fumigation method was modified to determine microbial biomass carbon and nitrogen in wet paddy field, together with soil ATP to find influences of long-term fertilization and flooding. Adenylate energy charge showed adaptation of microbes in paddy soil for anaerobic conditions and higher resilience than those in upland soils. Slowrelease fertilizer applied to 4 types of paddy soils did not change phospholipid fatty acid compositions of soil microbes as compared to urea application. Elevated CO2 concentration increased soil microbial biomass C in paddy soil along with rice growth, but did not microbial biomass N except in surface soil at harvesting time. Elevated CO2 concentration also increased CH4 emission from paddy field. Application of steel-making slag reduced CH4 emission and increased rice yield in Vietnamese paddy fields. Water-saving rice cropping also reduced CH4 emission and not changed rice yield and N2O emission in Indian paddy fields. Salinity tolerant cyanobacteria were isolated under water stress conditions in arid soil in Inner-Mongolia and Uzbekistan, showing plant growth resistance under saline conditions.