高CO2浓度对稻田CO2排放影响的初步分析

大气CO2浓度升高显著增加作物生物量，从而使进入土壤的有机碳增加，这势必会影响土壤碳的稳定和积累。此项研究主要通过高CO2浓度对作物生物量的直接影响，利用δ13C技术间接地初步分析土壤呼吸CO2排放不同来源贡献的差异。研究表明，在水稻生长季，高CO2浓度降低田间CO2的排放，但不显著；种有水稻，根系对土壤总的呼吸影响主要体现在成熟期之前，且有相互消长的现象。在种有水稻的情况下抽穗期之前分解新有机质为主；高CO2浓度促进土壤原有有机质的分解，在水稻生长的中后期分解更为明显，且高N水平对老有机质的分解有促进作用。鉴于此项研究中的不足之处，将会不断得到完善。

Primary Analysis in the Effects of Elevated [CO2] on Emission of CO2 from Rice Paddy Field

Elevated atmospheric CO2 concentration significantly increased crops biomass,which will input more carbon into soil to affect carbon stability and accumulation.This study was conducted indirectly in primary analysis of the effects of elevated CO2 on CO2 emission from different pools in rice paddy field based on the direct response of crops biomass to elevated CO2 and 13C isotope technique.Results show that in rice season elevated CO2 decreased the CO2 emission from field and not significant response was found.The effect of root on soil respiration was observed mainly before repining stage with fluctuation.Before earing stage soil new organic matter was decomposed more and elevated CO2 accelerate the decompose of old organic matter more from middle to end.High N level can improve the decompose of old organic matter.Considering the shortage in this study,the same and more work would be carried out in following.