Soil N 2 O emissions increased by litter removal but decreased by phosphorus additions

Nitrous oxide (N 2 O) and carbon dioxide (CO 2 ) emitted from forest soil are main greenhouse gases (GHGs). The nutrients released during litter decomposition and phosphorus (P) addition in forest soil may directly affect soil GHGs emissions. Cinnamomum camphora plantations are generally cultivated for leaf-harvesting for industrial purpose. Since C. camphora plantations are generally distributed in P-limited area, interactions between leaf-harvesting and P application may impact soil GHG emissions, which however, has rarely been studied. We conducted an in situ study to examine the effects of leaf-harvesting and P addition on soil N 2 O and CO 2 emissions over 14 months using full-factorial complete-randomized design. Litter removal was performed by removing all litter above the soil surface and P was added as nutrient solution. The results showed that N 2 O emission rates mainly depended on litter removal and its interaction with P treatment. Specifically, litter removal enhanced N 2 O emissions by 108%, while P addition reduced this enhancement by 39.7%. However, while P addition increased soil CO 2 emission rates by 6.7%, neither litter removal nor its interaction with P addition influenced soil CO 2 emissions. The results suggested that leaf-harvesting practice potentially enhanced N 2 O emissions from C. camphora plantation soil, while P management mitigated the enhancement. This study has implications for the management of leaf-harvesting C. camphora plantations concerning soil nutrient conservation and mitigation of forest soil GHG emissions, especially in forestry or agricultural soils in subtropical regions experiencing intensive leaf-harvesting management and fertilization practice.