The Effect Of Different Concentration Of CO₂ And O₂ On The Humus Formed By The Decomposing Corn Stover In Long-term Incubation

The indoor simulation test method,this paper studied the different concentration of O2(0%),B(4% ~ 7%),G(18% ~ 23%),D(82% ~ 87%),and different CO2 concentration C(48% ~ 52%),F(8% ~ 12%),G(< 2%)in long-term incubation(1080 D,1400 D,1080 D)on yield of corn stover forming soil corrosion mass(HS),humic acid(HA),fulvic acid(FA)and humin(HM)the influence of the number.Maize straw decomposition were emphatically studied on 1440 d,different concentration of O2 and CO2 HA and FA structure characteristics,the influence of to clarify the soil humus formation mechanism under different atmospheric conditions,to reveal the global climate change,the greenhouse effect under the condition of the response of soil organic matter has theoretical significance.The results are as follows:1.After adding maize straw,the content of soil organic carbon(SOC)was improved,with the concentration of 18% ~ 23% O2 concentration and <2% CO2 concentration,the concentration of SOC is highest.2.The use of maize straw was beneficial to the increase of WSS,and as the concentration of CO2 increased,the content of WSS increased,and its order was F>C> G.At different O2 concentration conditions,the high oxygen concentration(82-87%)was the highest concentration of WSS at 1080 d and 1800 d.3.Different concentration of O2 and CO2 under the condition of adding corn stover,FA,HA,iron combined with humin(HMi),a combination of clay humin(HMc),insoluble humin(HMr)content increased,the HMi components increase amplitude is higher than the HMc components,cultivate favorable for the formation of HMi components for a long time.The influence of different gas conditions on HA is different,and the concentration of O2 and CO2 is more favorable to the accumulation of soil HA.4.Under the conditions of different CO2 concentrations,the shrinkage and oxidation degree of FA were decreased after using corn stover,and the decrease of F treatment was significant,and the reduction of oxidation degree was most obvious in C.Under the conditions of different O2 concentrations,the addition of maize straw reduced the shrinkage of FA,and the treatment of FA was the most obvious.5.With the increase of concentration of O2,CO2 concentration,differential thermal analysis in the exothermic peak temperature and the ratio of exothermic peak temperature increases gradually,show that high O2 concentration and low CO2 concentration is more advantageous to the stability of HA.6.After adding corn stover,the lipids of FA increased with the increase of O2 concentration,and D treatment was the most significant.HA has decreased lipid,aromatic enhancement and B treatment is most obvious.On the contrary,with the increase of CO2 concentration,FA’s lipids decreased,aromaticity increased,and G treatment was most obvious.HA has enhanced lipids,decreased aromaticity,and has the most significant treatment of F.