不同填充剂对农村厨余垃圾堆肥氮转化及相关功能基因的影响

试验以农村厨余垃圾为堆肥原料，设置添加15%锯末（SD）、15%树叶（FL）和15%玉米秸秆（CS）3个处理。研究不同填充剂的添加对农村厨余垃圾堆肥过程中与腐熟度相关的各种理化指标，氮转化及其相关功能基因的影响。结果表明，添加3种填充剂的厨余垃圾堆肥产物均达到无害化处理标准，相比较SD处理，FL和CS处理提高堆体的最高温度并延长高温期的持续时间，FL处理腐熟程度最好，CS处理次之。相较于SD和CS处理，FL处理的NH₃累积排放量分别减少33.81%和5.22%，N₂O累积排放分别减少61.75%和29.10%，堆肥前期的反硝化基因降低明显。冗余分析结果表明，C/N、pH和全氮是造成厨余垃圾堆肥氮转化功能基因变化的主要因素。

Effects of Different Bulking Agents on Nitrogen Transformation and Related Functional Genes of Kitchen Waste Composting in Rural Area

In this study, kitchen waste in rural area in China was used as composting material, and three treatments with addition of 15% saw dust (SD treatment), 15% fallen leaves (FL treatment) and 15% corn stalks (CS treatment) were set. The effects of different bulking agents on various physicochemical indexes related to maturity, nitrogen transformation and related functional genes in the composting process of kitchen waste in rural area were investigated. The results showed that the composting products of kitchen waste with three bulking agents reached the harmless treatment standard. Compared with SD treatment, FL and CS treatment increased the maximum temperature of the composting piles and prolonged the duration of thermophilic period. FL treatment had the highest degree of maturity, followed by CS treatment. Compared with SD and CS treatment, the cumulative NH₃ emissions of FL treatment were reduced by 33.81% and 5.22%, and the cumulative N₂O emissions were reduced by 61.75 % and 29.10 %, respectively. Denitrification genes under FL treatment were significantly reduced at the early stage of composting. The results of redundancy analysis showed that C/N ratio, pH and total nitrogen were the main factors that caused the variation of nitrogen transformation function genes in kitchen waste composting.