沼气发酵不同物料比对氮素损失的影响及施用沼肥的增产效应

为探索沼气发酵的最佳物料比及施用沼肥的增产效应，分别在室内和田间进行了试验。结果显示，沼气发酵全氮平均损失率仅为482％，有效氮却为发酵前的354倍，发酵后有效氮占全氮的621％。沼气发酵处理产生有效氮量为堆肥发酵有效氮量的613倍。沼气发酵法中的氮素损失率按以下次序递减: 处理1(猪粪∶稻草=4∶1)(997%)> 处理2(猪粪∶牛粪∶稻草=1∶1∶05)(434%)> 处理3(猪粪∶牛粪∶人粪=3∶1∶1)(268%)。沼气发酵的氮素有效化率平均比堆肥发酵高415倍。在不同土壤中，水稻、玉米、小麦、棉花、油菜上施用沼肥的增产率为65%～157%，平均增产达到1138%。

Effect of different material ratio on nitrogen loss during biogas fermentation and yield improving effects of application of biogas fertilizer on crops

Laboratory and field experiments were conducted to determine the effects of different material ratios on nitrogen loss during biogas fermentation and yield improving effects of application of biogas fertilizer on crops. The results showed that the average nitrogen loss of biogas fermentation was 482%. Available N in the biogas liquid after the fermentation was increased by 254 times than that before the fermentation. Available N in the biogas liquid after the fermentation accounted for 621% of total N. Available N in the biogas liquid for the biogas fermentation was 513 times greater than that for the compost fermentation. Nitrogen loss in the biogas liquid for the biogas fermentation was in the following order: Treatment 1(pig manure∶straw=4∶1)(997%)> Treatment 2(pig manure∶cow dung∶straw=1∶1∶05)(434%)> Treatment 3(pig manure∶cow dung∶human fxces=3∶1∶1)(268%). Available rate of N in the biogas liquid for the biogas fermentation was 415 times greater than that for the compost fermentation. Under different soils， the yield increase rates of rice， corn， wheat， cotton， and rape with application of biogas fertilizer were 65%-157% with an average value of 1138%．