The effect of varying gamma irradiation doses and soil moisture content on nematodes, the microbial communities and mineral nitrogen

摘要: Abstract Gamma irradiation is becoming a potential tool in soil ecological studies as it gives possibility to vary dose that selectively kills the target organism. It makes minimum changes biochemical properties compared autoclaving and freezing. Although gamma has often been used studying roles of nematodes on nutrient cycling, recommended doses eliminate still lead flush, are less reproducible. Given indirect effect through radiolysis, same might have different moisture content changes. Thus, an optimal eliminates needs be determined taking sample at time into consideration. We conducted incubation experiment for about three months during which effects range low (0, 1, 3 5 kGy) (air dried, 50% water filled pore space (WFPS), 80%WFPS) were tested nematode abundance selected properties. Leaching with immediately after 50%WFPS, was assess what extent would remove N from flush. The results showed increases 50%WFPS 80%WFPS, abundance, enzyme activities total mineral concentrations decreased most period each dose. Increasing content, however, did not make significant phospholipid fatty acid all levels irradiations except 3 kGy. These findings indicate biological chemical depending irradiation. Moreover, need considered optimizing selective sterilization or defaunation. In current experimental set up, application 3 kGy 80%WFPS eradicated left comparable microbial community structure unirradiated CTR. samples irradiated 5 kGy generally significantly reduced both NH 4 + -N NO − concentrations, but concentration remained higher This indicates leaching only partly flush underlines test additional methods reduce further.