Responses of N2O Flux from Forest Soils to Land Use Change in Subtropical China

Abstract

To evaluate the effect of land use change from a natural broadleaf evergreen forest to Moso bamboo plantations and their management practices on soil N2O efflux in a subtropical region of China, N2O efflux was measured during June 2008 and May 2009 using static closed chamber method. The observed mean N2O fluxes were 0.230, 0.102 and 0.093 mg N2O/m2/h from the intensively managed bamboo forest (IM), conventionally managed bamboo forest (CM), and broadleaf evergreen forest (BL), respectively, and calculated annual cumulative N2O were 15.8, 8.7 and 7.2 kg N2O/ha, respectively. Soil temperature had significant influence on N2O flux. Whereas there was no correlation between N2O flux and soil water content. Conversion of the natural subtropical broadleaf evergreen forest to Moso bamboo did not increase soil N2O efflux, but intensive management practices such as regular tillage and fertiliser application, significantly increased soil N2O emission from bamboo soil.