不同动物排泄物氮的作物利用及对N2O排放的贡献

本文用同一种土壤,在不同水分管理模式下,种植两种作物,以不施 N 作为对照研究了人粪、猪粪、奶牛粪和鸡粪作肥料与尿素等 N 量施用,对小米和水稻籽粒产量、N 素利用率的影响以及对N20排放量的贡献.尿素与4种粪肥对小米和水稻产量、N素利用率和N20排放的贡献并不相同.水稻产量以施用尿素最高,施用鸡粪产量效应最低,与不施N处理接近,但旱作小米以施用人粪最高,其次为尿素和鸡粪处理.水稻和小米对N素的回收率均以尿索为最高,其次为人粪、鸡粪和牛粪,猪粪最低.尿素和4种粪肥处理,在小米播种和水稻移栽后的第2天均出现了N20的排放高峰.由于两种作物水分管理不同,N20排放高峰持续时间不同,水稻长于小米.在水稻烤田前后的干湿交替过程中,不同肥料处理均出现了N20的第2次排放高峰,除牛粪和猪粪处理外,N20 峰值的持续时间长达10天左右.N20排放总量在旱作小米生长季以人粪处理最高,尿素,鸡粪和猪粪处理接近,牛粪处理最低.水稻生长季N20排放量以尿素处理为最高,依次为人粪、鸡粪处理和猪粪处理,牛粪处理最低,与不施N处理接近.

Nitrogen Utilization Ratio and N2O Emission from Different Animal Manures

A pot experiment was conducted to compare the effects of organic fertilizer and chemical nitrogen fertilizer on crop yield, nitrogen utilization ratio and nitrous oxide (N2O) emission. Urea and four organic fertilizers including human manure, pig manure, cattle manure and chicken manure were applied to rice and millet at ·N 300 kg/hm2 while zero nitrogen treatments were included as control. Urea treatment had the highest rice yield among all the fertilizer treatments while chicken manure treatment had the lowest close to zero nitrogen treatment. As for millet yield, however, human manure treatment had the highest yield, followed by urea and chicken manure. Nitrogen utilization ratios of the organic and chemical fertilizers showed the same order in rice and millet, namely, urea>human manure>chicken manure>cattle manure>pig manure. Nitrous oxide emission reached the first peak one day after the sowing of millet and the transplanting of rice for all the organic and chemical fertilizer treatments, and the peak from rice lasted longer than that from millet due to the difference in water management in the two crops. A second N2O emission peak occurred during the middle season drainage period of rice and lasted about 10 days. Seasonal N2O emission from millet was the highest in human manure treatment and the lowest in cattle manure treatment, while seasonal N2O emission from rice was the highest in urea treatment and the lowest in cattle manure treatment close to zero nitrogen treatment.