奶牛粪好氧堆肥过程中不同含碳有机物的变化特征以及腐熟评价

Change patterns of different carbon-containing compounds in dairy manure during its aerobic composting and assessment of composting maturity

对奶牛粪好氧堆肥过程中不同含碳有机物的变化特征以及腐熟程度进行了研究。根据腐熟指标(温度、种子发芽率、种子发芽指数、大肠杆菌以及蛔虫卵死亡率)的要求,奶牛粪经过堆肥后能够达到腐熟要求。堆肥过程中全碳、易氧化有机碳呈逐渐下降趋势,腐殖酸碳呈逐渐增加的趋势;微生物量碳和水溶性碳呈先增后降而后平稳的变化趋势;氧化稳定系数和H/F比(胡敏酸与富里酸比值)呈先降后增的变化趋势,而胡敏酸的E4/E6值(465和665nm处吸光系数比值)与氧化稳定系数和H/F比变化趋势相反。通过相关性分析发现,堆肥过程中易氧化有机碳和腐殖酸碳是影响全碳变化的主要因素;易氧化有机碳、腐殖酸碳、氧化稳定系数、H/F比、E4/E6值均能很好地表征奶牛粪堆肥的腐殖化和稳定化程度;微生物量碳和水溶性碳之间存在相互转化的关系。

An investigation was conducted on the change patterns of different carbon-containing compounds in dairy manure during its aerobic composting,and an assessment was made on the composting maturity,based on the changes of maturity indices.According to the requirements for maturity indices（temperature,seed germination rate,germination index,coliform flora,and mortality of ascarid egg）,the dairy manure after composting could reach the demand of maturity.During composting,the contents of total carbon and readily oxidizable carbon in the manure decreased,but that of humic acid carbon increased.The microbial biomass carbon and water soluble carbon increased（0-14 d）first,decreased（14-28 d）then,and kept stable finally（28-70 d）.Kos（oxidation stability factor）and the H/F（humic/fulvic acids）ratio decreased first（0-14 d）and increased then（14-70 d）,while the E4/E6（absorption coefficient ratio of 465 nm to 665 nm）of humic acid carbon had a change trend opposite to Kos and H/F ratio.Through the correlation analysis among different organic carbon-containing compounds,it could be drawn that readily oxidizable carbon and humic acid carbon were the main factors affecting the change pattern of total carbon during composting,and the readily oxidizable carbon,humic acid carbon,Kos,H/F ratio,and E4/E6 could well express the humification and stability degree of dairy manure compost.During composting,microbial biomass carbon and water soluble carbon could transform each other.