不同氮源对秸秆堆沤氮素损失的影响

试验以玉米秸秆为研究对象，比较以硫酸铵或尿素为氮源调节碳氮比后对纳米膜覆盖发酵过程中的NH₃排放和堆沤产物氮素留存的影响，为减少秸秆好氧堆沤过程中的氮素损失提供参考依据。结果表明：堆沤7～60 d硫酸铵处理的发酵温度高于尿素处理；尿素处理膜内NH₃最高浓度为0.045%，而硫酸铵处理自始至终膜内侧NH₃未检测出；试验结束后尿素处理0和50 cm处的pH值分别上升至8.34和7.86，硫酸铵处理pH值分别下降至6.04和6.28；硫酸铵处理堆沤产物的干物质损失率、总养分含量、种子发芽指数和胡富比均高于尿素处理；相对于尿素处理，硫酸铵处理的氮素损失率减少了24.59%；除含水率外，尿素处理和硫酸铵处理堆沤产物的理化性质均符合NY/T 525—2021《有机肥料》的限量要求。

Effects of Different Nitrogen Sources on Nitrogen Loss in Straw Composting

In order to reduce nitrogen loss in process of corn straw aerobic composting, C/N value was adjusted by ammonium sulfate or urea, and ammonia emission and nitrogen retention in process of composting covered by nano membrane were tested．Results showed that fermentation temperature of ammonium sulfate treatment（T₂）from 7 d to 60 d was higher than that of urea treatment（T₁）．The maximum concentration of NH₃ in membrane of T₁ was 0.045%, while NH₃ was not detected in membrane of T₂．Composting products' pH values at 0 cm and 50 cm of T₁ increased to 8.34 and 7.86, which of T₂ decreased to 6.04 and 6.28 respectively．Dry matter loss rate, total nutrient content, seed germination index and C_HA/C_FA of composting products in T₂ were higher than those in T₁．Compared with T₁, nitrogen loss rate of T₂ was reduced by 24.59%．Except water content, physicochemical properties of composting products of T₁ and T₂ met requirements of NY/T 525—2021 "Organic Fertilizer"．