【摘要】 应用15N示踪方法 ,研究了稻田农牧沼生态系统中N的储存、转化、流向及其利用效率。证明猪对紫云英青贮饲料中粗蛋白质的消化率为 53.76 % ,猪粪和猪尿对青贮饲料中N的回收率分别为 39.36 %和 2 4 .71% ,猪粪尿沼气发酵 ,N的回收率达 97.9% ,水解N含量为发酵前的2 .6倍。绿肥和沼肥与化肥配合施用能促进N向稻谷转移 ,从而有利于产量的提高 ,且肥料N在土壤中的残留量相当于单施化肥的 2～ 2 .5倍 ,而气态损失N ,后者为前者的 2 .6～ 8.2倍。整个系统的综合经济效益比单纯的肥稻稻增加 3～ 4倍 ,生态效益和社会效益显著更多还原

【Abstract】 N ?labeled technique was used to study the fixation, transformation, fate and utilized efficiency of N in the farming ?stockbreeding ?biogas ecosystem of rice areas. The results showed that the crude protein digestibility of the ensilaged milk vetch by pig was 53 76%, the recovery rates of ensilaged milk vetch N by the pig feces and urine were 39 36 % and 24 71 %, respectively. The recovery rate of N of pig feces and urine was 97 9% for biogas fermentation. The content of hydrolyzable N in biogas fertilizer was 2 6 times higher than before the fermentation. The combined application of milk vetch, biogas fertilizer and chemical fertilizer can promote N translocation to rice grain to increase the yield. The residual N of fertilizer in soil and gaseous loss N in combined application of milk vetch, biogas fertilizer and chemical fertilizer was 1 0～1 5 times higher and 1 6～7 2 lower than that in the treatment of chemical fertilizer alone, respectively. The comprehensive economic benefit in the farming ?stockbreeding ?biogas ecosystem increased by 300%～400%, compared to that of milk vetch ?early rice ?late rice system, and ecological and social benefit were also significant.更多还原