生物炭与氮肥施入对夏玉米农田氮素淋失与利用的影响

Effects of Biochar and Nitrogen Fertilizer Application on Nitrogen Leaching Loss and Utilization in Summer Corn Fields

为了研究生物炭与氮肥施入对夏玉米农田氮素迁移转化规律、氮肥利用效率及产量的影响,开展夏玉米种植测坑试验,设置氮肥施入量和生物炭施入量2个因素,其中氮肥施入量设置150、200 kg/hm^(2)2个水平,生物炭施入量设置0、20、40 t/hm^(2)3个水平,共设计7个处理方案。结果表明:与无生物炭施入的处理方案相比,生物炭施入处理的土壤含水率增大0.52%~58.85%,土壤硝态氮、氨态氮质量分数增大0.48%~436.49%,土壤淋失液中硝态氮、氨态氮总淋失量减小30.46%~83.20%,并且随着生物炭施入量的增大,生物炭的保水保肥功效更明显;当氮肥施入量为200 kg/hm^(2)且生物炭施入量为40 t/hm^(2)时,作物的氮肥农学利用率和氮肥偏生产力最大,夏玉米产量达到11748.86 kg/hm^(2),生物炭施入能使土壤氮素减损,节氮增效,促进夏玉米增产、增收。

To investigate effects of biochar and nitrogen fertilizer application on nitrogen migration and transformation laws,nitrogen fertilizer utilization efficiency,and yield in summer corn fields,a pit test on summer corn planting was conducted.Two factors of nitrogen fertilizer application amount and biochar application amount were set.Two levels of the nitrogen fertilizer application amount were set at 150 kg/hm^(2) and 200 kg/hm^(2),and three levels of biochar application amount were set at 0,20 t/hm^(2) and 40 t/hm^(2).A total of seven treatment schemes were designed.The results show that compared with the treatment scheme without biochar application,the water content in soil increases by 0.52%-58.85%,the mass fraction of nitrate and ammonia nitrogen in soil increases by 0.48%-436.49%,and the total leaching loss of nitrate and ammonia nitrogen in soil leaching solution decreases by 30.46%-83.20%.The water and fertilizer retention effect of biochar was more obvious with the increase of biochar application amount.When the nitrogen fertilizer application amount is 200 kg/hm^(2) and the biochar application amount is 40 t/hm^(2),the agronomic utilization rate of nitrogen fertilizer and the partial productivity of nitrogen fertilizer reach the maximums,and the yield of summer corn reaches 11748.86 kg/hm^(2).The biochar application can reduce the loss of nitrogen in soil,save nitrogen and improve efficiency,and promote the yield and income of summer corn.