【作者】 高翔；

【导师】 邹建文；

【作者基本信息】 南京农业大学 ， 生态学， 2016， 硕士

【摘要】 为了探究农业废弃物常规堆置与条跺式堆肥过程温室气体的排放机理,也为估算全球温室气体排放与探寻减排措施提供部分可靠的数据支撑和理论依据。本文以畜禽粪便和农作物秸秆为主要原料,通过原位观测试验,研究农业废弃物CF(常规堆置)与OF(条跺式堆肥)过程温室气体排放通量的变化特征;并结合理化因子,初步阐明CF与OF过程中理化因子对温室气体排放的影响机制,比较分析了二者之间的温室气体排放差异。主要结果如下:整个农业废弃物CF和OF过程,CO2排放主要来自转移堆体之前的0～21d,CH4的主要释放时间分别为第28～42d和第0～21d,N2O的主要排放分别来源于第12～28d和第43～62d。CF过程中,CO2的排放通量在起始时刻即达到最大峰值58.78mg·kg-1·hr-1;CH4排放的最大峰值出现在第10d,为0.41mg·kg-1·hr-1;而N2O的排放通量在转移堆体的剧烈干扰下,第21d出现一个特殊的峰值高达78.73μg·kg·-1 ·hr1。OF过程中,CO2和CH4的排放通量均在第4d达到最大峰值,分别为135.27mg·kg-1·hr-1和1.19mg·kg-1·hr-1;N2O的排放通量整体呈不断上升的趋势,OF在周期结束时达到最大值9.01μg kg-1 hr-1。与CF相比,农业废弃物进行OF处理分别增加了 226.2%和374.6%的CO2和CH4排放,但能够减少72.5%的N2O排放。碳素的损失主要来自CO2,在CF和OF过程分别占初始TOC(总有机碳)的8.79%和17.74%,而CH4-C仅占0.13%～0.33%,以N2O形式损失的氮素分别占TN的0.11%和0.04%。另外,由CO2、CH4和N2O三种气体排放所带来的GWP100(全球增温潜势)中,以CO2的排放为主,占总量的80%左右,CH4次之,N2O最少。相比CF,农业废弃物的OF处理明显增加了温室气体排放所产生的GWP100,增加了约217%。堆体的MC(含水率)和TOC为CO2排放最主要的影响因子。忽略时空差异,CF和OF过程79.63%的CO2排放可以由MC来解释。而TOC不论是CF的低水平还是OF的高水平条件下,CO2排放通量都与TOC呈极显著线性正相关,且趋势线斜率大小相近。另外,CF过程CO2排放也在一定程度受到pH值、TN(全氮)和C/N值的影响。CF过程中,PT(堆体温度)和TOC是CH4排放的主要影响因子;而在OF过程,堆体MC和TOC才是CH4排放的主要影响因子。整个CF和OF过程,PT、NH4+-N和NO3--N均是N2O排放的重要影响因子。此外,CF过程中N2O的排放对堆体pH值和TN的变动具有一定程度的响应,OF过程中堆体MC也是影响N2O排放的一个主要因子。更多还原

【Abstract】 Our goals were to explore the mechanism of GHGs emissions in the conventional piling(CF)and windows composting(OF)processes of agricultural residual.Also,we hoped we could provide some reliable data and theories for estimating global GHGs emissions and exploring the way of reduction.In this paper,we chose the livestock,poultry manure and crop straw as the main raw materials.We conducted an observation experiment in situ to study the scenarios of GHGs emission fluxes in CF and OF.Physicochemical factors were considerd to preliminarily elucidate their effects on GHGs emissions,and then we compared the differences of GHGs emission between CF and OF processes.The main results were as follows:The CF or OF process of agricultural residual released the majority of CO2 during the first 21 days,and released the majority of CH4 during 28～42 days and 0～21 days,respectively.N2O emissions were mainly derived from 12～28 days for CF process,and 43～62 days for OF process.The maximum peak of CO2 emission fluxes occurred at the beginning and reached 58.78 mg·kg-1 hr-1 for CF,and the macimun preak of CH4 occurred on 10th day and reached 0.41 mg·kg－1·hr-1.However,N2O emission fluxes had a special peak as high as 78.73 μ·kg-1·hr-1 on 21th day in the CF process due to severe interference when the pile was moved.In the OF process,the maximum peak of CO2 and CH4 emission fluxes both occurred on the fourth day and reached 135.27 and 1.19 mg·kg-1·hr-1 respectively,and the N2O emission flux increased to the maximum peak at 9.01 μg·kg-1·hr-1 by the end.Compared with the CF,the OF process increased CO2 and CH4 emissions by 226.2%and 374.6%,respectively,but reduced 72.5%N2O emission.In the CF and OF process,CO2 as main carbon loss form accounted for 8.79%and 17.74%of the initial TOC respectively,and a carbon loss form of CH4-C only accounted for 0.13%～0.33%for the two processes.Nitrogen loss in the form of N2O emission accounted for 0.11%and 0.04%of TN for CF and OF process,respectively.In addition,the amount of GWP100 was produced by three GHGs emissions which CO2 accounted for about 80%of the total amount,and secondary GHGs emission was CH4.Agricultural residual OF treatment significantly increased about 217%GWP100 production relative to CF treatment.In the CF or OF process,MC and TOC were the main factors on CO2 emission.About 79.93%of CO2 emissions could be explained by the MC when ignored time and space differences.The TOC and CO2 emission had significant linear positive correlation and the trend line slope close to the same value under the conditions of CF or OF treatment,no matter at low or high level.Besides,pH,TN and C/N would partly influence CO2 emission in the CF process.PT and TOC were main factors that affected CH4 production in the CF process.However,MC and TOC were main factors that influenced the CH4 emission in the OF process.In the CF or OF process,PT,NH4+-N and NO3--N were all the important factors that impacted N2O emission.Furthermore,MC was also a major factor affecting N2O emission in OF,and N2O had a certain degree of response to variations of pH and TN in CF.更多还原