Abstract:
Fluxes and cumulative emissions of CO
2 and N
2O from red soil duting the wheat and corn seasons under different patterns of long-term fertilization(CK,NP,NK,NPK and NPKM)were monitored by making use of the long-term,16-year wheat-corn rotation experiment on upland red soil in the Qiyang Red Soil Experiment Station,Chinese Academy of Agricultural Sciences.The static dark chamber method and gas chromatograph technique were used to collect and measure concentrations of CO
2 and N
2O.Results show that emissions of CO
2 and N
2O varied obviously with the seasons.Fertilization significant affected the emissions of CO
2 and N
2O,and application of manure significantly promoted the emission of CO
2 and N
2O.The cumulative emission of CO
2 from Treatment CK,NP,NK,NPK and NPKM was measured to be 5904,8062,4298,9235 and 14098kg•hm
-2 and 4708,7530,5435,7089 and 15472kg•hm
-2,respectively,in the wheat season and corn season,and the cumulative emission of N
2O,0.34,0.63,0.44,0.62 and 1.00kg•hm
-2 and 0.25,0.39,0.35,0.52 and 1.73kg•hm
-2.On average,the cumulative emissions of CO
2 and N
2O during the wheat fallow period accounted for 63.52% and 28.43%,respectively,of the total of the whole wheat season,and the cumulative emissions of CO
2 and N
2O during the corn fallow period for 49.98% and 32.72%,respectively,of the total of the whole corn growth season,which suggest that emission of CO
2 and N
2O during the fallow season should not be neglected.Flux of CO
2 emission in all the treatments was significantly related to soil temperature at 5 cm depth,except for Treatment NP,NK and NPK in the corn season,but flux of N
2O emission was not in any of the treatments.None of the treatments,except for Treatment NPKM,showed any significant relationship between flux of CO
2 or N
2O emission and soil water content.