Diversity and community structure of ammonia oxidizing archaea in long term fertilized paddy fields

Long-term experiments involving different fertilization practices have been conducted at Miryang research station, South Korea since 1967 for the purpose of studying how varying fertilization regimes influence soil parameters and crop yield. By utilizing this long-term study site, the first objective in our study was to investigate the changes in population size of ammonia oxidizing microbes in response to different treatments owing to their importance in the process of nitrogen cycling. The second objective was to compare the community composition of ammonia oxidizing microbes and then to assess the relationship between differences in abundance of composition and particular soil parameters. Integrated approach was employed to achieve these objectives by estimating the soil enzymatic activities and nitrification potential, quantifying the amoA copy number by quantitative polymerase chain reaction and exploring the diversity and community of nitrifying microbes by barcoded 454 pyro sequencing.