Mangrove swamps are considered to be a potential net source of greenhouse gases,but the fluxes of greenhouse gases from mangrove soils are still poorly characterized.The present study,conducted in July 2012 in 3 Kandelia candel mangrove forests in Jiulongjiang Estuary in southern China,aimed to investigate the summer fluxes of N_2 O,CH_4 and CO_2 from the soil and the role of soil characteristics in regulating gas fluxes.Gas fluxes ranged from 0.27 to 2.45 mumol/(m~2· h),-0.28 to 341.43 mumol/(m~2· h)and -0.49 to 17.00 mmol/(m~2· h) for N_2 O,CH_4 and CO_2, respectively,indicating that mangrove soil was an emission source of greenhouse gases in Jiulongjiang Estuary in summer.Total CO_2-equivalent fluxes of the three gases,indicating their global warming po-tential,ranged from 82.33 to 674.92 mg /(m~2 · h),and CO_2 was the most dominant in the total flux in the man-groves.This study recorded higher CO_2 at the landward site than middle zone and seaward site,while there were no differences in both N_2 O and CH_4 fluxes among different tidal positions.Soil characteristics also varied with mangrove transect or sampling position.These characteristics,especially nutrient contents were factors regulating greenhouse gases emissions and their spatial variations in mangrove.N_2 O and CO_2 fluxes were positively related to soil organic matter,ammonium and total nitrogen concentrations,and CH_4 flux showed significant and negative correlation with the redox potential(E_h).