利用鸡粪和粉碎小麦秸秆为原料进行了C/N比分别为12.4、17.4、31.2、35.2的自然通风静态堆肥对比试验,定量化研究了堆肥过程中不同阶段各种形态氮素转化和氮素损失途径.结果表明,TOC随着堆肥的进行逐渐降低,C/N比越低堆肥TOC的降解越少;低C/N比堆肥的全氮含量呈下降趋势,高C/N比堆肥处理的含氮量呈上升趋势.堆肥过程中的C/N比均呈下降趋势,其中31.2C/N和35.2C/N2个处理的C/N比下降明显,12.4C/N和17.4C/N堆肥处理的C/N比变化不大.12.4C/N17.4C/N、31.2C/N35.2C/N4个堆肥处理的氮素损失率分别为58.7%、60.2%、37.7%、23.3%.氮素损失的主要途径为铵态氮以氨气的形式挥发,堆肥的3～7 d是氮素损失的主要时期.堆肥过程中氨态氮和有机氮的变化最大,硝态氮变化较小,主要在堆肥后期略有形成,堆肥28 d时,所有堆肥处理硝态氮含量占总氮含量变化为0.58%～0.25%.堆肥C/N比越低,有机氮损失越多,氨态氮损失越小.高C/N比堆肥氨态氮不仅损失少,而且向有机氮转化.
Co-composting tests with C/N 12.4, 17.4, 31.2 and 35.2 using poultry manure and wheat straw as raw composting materials were conducted under natural ventilation. Various kinds of nitrogen transform and loss way were determined at different composting stages. The results indicated that TOC reduced gradually with the composting time. The lower the ratio of C/N, the less the degradation of TOC, and the total nitrogen in compost tended to decrease at low C/N, thosewere the contrary at high C/N. During composting, the ratio of C/N tended to decrease, the treatments of 31.2C/N and 35.2C/N decreased remarkably, but changed a little at the treatments of 12.4C/N and 17.4C/N. For the four compost treatments of 2.4 C/N, 17.4 C/N, 31.2 C/N, <IMG SRC='IMAGE/03230144.JPG' HEIGHT=11 WIDTH=18><IMG SRC='IMAGE/03230145.JPG' HEIGHT=9 WIDTH=18>35.2C/N, the rate of nitrogen losing was 58.7%, 60.2%, 37.7%, 23.3%respectively. Main way of nitrogen losing was volatilization in the form of ammonia originated from ammonium. The main period of nitrogen losing was 3～7 d. The -N and Org-N during composting changed remarkably; while, -N changed a little and only happened on laterstage of composting, at 28 day of composting, the change percentage of NO3-N content accounted for only 0.25%～0.58%of total N change. Lower C/N resulted in more loss of Org-N and less loss of NH3-N in the compost, while higher C/N in composting not only led to less loss of NH3-N but also made NH3-N turn into Org-N.
Journal of Agro-Environment Science( J. Agro-Environ. Sci.)