5 Conclusion
Soil N mineralization and availability are crucial for ecosystem productivity and carbon sequestration, especially in the context of global climate change or anthropogenic disturbances. The frequency of N addition and mowing had only occasional effects on those variables, which likely due to the effects of the frequency of N addition and mowing were offset by the effects of the levels of N addition, or that interactions of these with other human or environmental factors that we did not examine occurred. Nevertheless, GA and GN were significantly affected by N addition frequency and mowing especially at the highest N addition level. Consequently, long-term research on the response of N cycling to human activities or environmental variables is needed to further improve our understanding of the response mechanism of N cycling to climatic change.