碳与氮质量比对鸡粪与玉米秸秆混合堆肥的影响

Effects of different mass ratios of C to N on co-composting chicken manure and maize straw

以新鲜鸡粪和玉米秸秆为堆肥原材料,调节堆体初始碳与氮质量比分别为14(堆体1)、18(堆体2)和30(堆体3),采用连续强制通风方式进行混合堆肥。研究温度、pH、电导率(EC)、有机质(OM)、总氮(TN)、总磷(TP)、阳离子交换量(CEC)和种子发芽指数(GI)等与堆肥产品质量和腐熟度密切相关的指标关系,并以此评价不同碳与氮质量比对堆肥产品质量和腐熟度的影响。结果表明:堆体3温度高于50℃的时间可维持5 d,较堆体1(2 d)和堆体2(4 d)的高温时间长;堆体3的最终EC和CEC分别为1 070μs/cm和1.456 mol/kg,与堆体1和2相比,其堆肥质量更佳;堆肥结束时,堆体1,2和3的OM含量下降约30%,而TN和TP含量未发生显著变化;堆体1,2和3的最终GI分别为61%,70%和82%。因此,初始碳与氮质量比为30的鸡粪和玉米秸秆混合堆肥(堆体3)能获得质量和腐熟度更好的堆肥产品。

The evolution of both nutrient and physicochemical parameters of compost throughout the forced-aeration composting process of chicken manure and maize straw with different initial C/N ratios of 14 （pile 1）, 18 （pile 2）, and 30 （pile 3） were investigated, respectively, and thereby the quality and degree of maturity of compost were evaluated so as to decide the optimized proportion of both raw materials. The duration of temperature exceeding 50 ~C of pile 3 maintains 5 d, which is longer than that of pile 1 （2 d） and pile 2 （4 d）. Electrical conductivity （EC） and cation exchange capacity （CEC） of pile 3, with the ultimate value of 1 070 kts/cm and 1.456 mol/kg, indicate higher quality of compost, compared with that of piles 1 and 2. Also, the organic matter （OM） contents of three piles degrade by 30% or so, while total nitrogen （TN） and total phosphorus （TP） contents show a steep fluctuation during the composting period, only with a slightly increase in both contents. As to phytotoxicity assay, the final germination index （GI） reaches 61%, 70%, and 82% for piles 1, 2, and 3, respectively. Therefore, C/N ratio of 30, demonstrates as pile 3, can be the optimum option compared to that of piles 1 and 2 from co-composting chicken manure and maize straw.