Research on N2O Emission Fluxes of 3 Cultivated Grasslands in Growing Seasons
In order to determine the relationships between the N2O emission fluxes of cultivated grassland in growing season and soil moisture,temperature,nitrate nitrogen content or ammonium nitrogen content,the N2O emission fluxes of Kentucky bluegrass (Poa pratensis),lucerne (Medicago sativa) and sainfoin (Onobrychis viciaefolia) cultivated grasslands were observed during growing seasons in the Loess Plateau using a static chamber-HPLC method.The results showed that N2 O emission fluxes had significant difference in among 3 cultivated grasslands(P＜0.05),Kentucky bluegrass grassland had the highest N2O emission fluxes.The N2O emission fluxes of Kentucky bluegrass,sainfoin and lucerne grassland were -0.3185～0.4943,-0.4962～0.4755,-0.3167～0.4620 mg· m 2 · h-1,respectively.TheN2O accumulated emission fluxes of Kentucky bluegrass grasslands was obviously higher than those of lucerne and sainfoin.The N2O emission fluxes of 3 cultivated grasslands reached the peak during florescence,while N2O absorption was observed during regenerative phase.The N2O emission fluxes of Kentucky bluegrass was mainly affected by soil moisture,and the N2O emission fluxes of two legume cultivated grasslands were related with the contents of nitrate-N and ammonium-N.
NETL
NSTL
万方数据
维普
