Interactive Effects of Compost Type and Temperature on Nitrous Oxide Emissions from Agricultural Soil

Agricultural soils are a major anthropogenic source of nitrous oxide (N2O), primarily through microbially mediated nitrogen transformations. This study investigated the interactive effects of manure compost type and temperature on N2O emissions under controlled aerobic incubation conditions. Soil samples amended with either cattle compost (CC) or poultry compost (PC) were incubated for 35 days at three temperature regimes: 20°C, 30°C, and 40°C. N2O emissions were measured periodically on days 3, 7, 14, 21, 28, and 35. The addition of PC consistently resulted in higher N2O emissions than CC, and N2O emissions generally increased with temperature up to 30°C. However, a significant interaction effect between compost type and temperature was observed: while N2O emissions from CC continued to rise at 40°C, those from PC declined. These results indicate that compost characteristics can modulate the temperature sensitivity of N2O production. Future studies integrating microbial and enzymatic indicators would help confirm the mechanisms underlying the observed interaction. This study highlights the need to consider the combined influence of compost properties and temperature when managing organic amendments, as single-factor assessments may overlook critical interactions governing N2O emissions.