College of Resources and Environment, Northeast Agricultural University, Harbin 150030, China.
College of Resources and Environment, Northeast Agricultural University, Harbin 150030, China; Institute of Natural Resources and Ecology Heilongjiang Academy of Sciences, Harbin 150040, China.
Bioresour Technol. 2021 Mar;323:124572. doi: 10.1016/j.biortech.2020.124572. Epub 2020 Dec 28.
This study investigated nitrification process during cattle manure-maize straw (CM) and biochar (CMB) composting in terms of multi-variable interaction (MVI) among environmental parameters, ammonia-oxidizing archaea (AOA) and bacteria (AOB) community structure, nitrogen-related enzymes as well as substrates using structural equation model (SEM). Results showed that adding biochar significantly reduced potential ammonia oxidation rates. SEM analysis revealed that AOB was affected by temperature and pH, which stimulated the release of urease, increased NH-N concentration and finally exerted influence on nitrification in CM. Temperature (0.755) and NO-N (-0.994) were identified as the main factors mediating nitrification in CM and CMB, respectively. Moreover, MVI analysis indicated that nitrification and denitrification occurred simultaneously. Mutual verification of SEM and quantitative analyses (RNA level) confirmed that AOB predominated nitrification. The above results indicated that nitrification could be better explained by MVI using SEM during composting.
本研究采用结构方程模型（SEM），从环境参数、氨氧化古菌（AOA）和细菌（AOB）群落结构、氮相关酶以及底物的多变量相互作用（MVI）角度，研究了牛粪-玉米秸秆（CM）和生物炭（CMB）堆肥过程中的硝化过程。结果表明，添加生物炭显著降低了潜在氨氧化速率。SEM 分析表明，AOB 受温度和 pH 值的影响，这刺激了脲酶的释放，增加了 NH4+-N 浓度，最终对 CM 中的硝化作用产生影响。温度（0.755）和 NO3--N（-0.994）分别被确定为 CM 和 CMB 中硝化作用的主要调节因子。此外，MVI 分析表明，硝化和反硝化同时发生。SEM 和定量分析（RNA 水平）的相互验证证实，AOB 主导硝化作用。上述结果表明，在堆肥过程中，通过 SEM 进行的 MVI 可以更好地解释硝化作用。
