Influence Of Black Carbon Addition On Nitrous Oxide Emission And Nitrogen Leaching From Subtropical Forest Soils

Impacts of black carbon (BC) addition on nitrogen (N) transformation processes in forest soils have not well reported. In this study, black carbon materials were produced and mixed with the Cunninghamia lanceolata soil and Altingia gralilipes community soil at application rate of0%,1%and5%with or without nitrogen (N) fertilizer. We investigated that the influence of black carbon addition on greenhouse emission (N2O and CO2) and nitrogen leaching in subtropical forest soils. The study will provide valuable information on evaluating the role and function of BC in soil C and N cycle. The major resulits are summarized as follows:Black carbon addition significantly increased soil N2O fluxes by54%, and obviously occured due to N addition in Cunninghamia lanceolata soil. On the contrary soil N2O were markedly reduced by black carbon addition in Altingia gralilipes community soil,In comparison with other treatments in Cunninghamia lanceolata soil, the CO2fluxes significantly increased by108.7%,36.8%and42.2%with the higher BC-amended treatments (S5, SL5and SH5), respectively. And this effect was more obvious at the earlier stage of incubation, while no clear effect was observed in Altingia gralilipes community soil.Black carbon application influenced the nitrogen leaching in two forest soils, and its loss also depended on soil type, nitrogen level, black application rate and their interaction. During the first leaching event, there was a significant decrease in total amounts of nitrogen leaching with increasing of black carbon application rate, and total nitrogen loss decreased by23%and52.9%in higher BC-amended treatments (SH5and XH5), respectively.