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利用田间小区试验研究了小麦-玉米轮作中在不同施氮量和不同时期潮土1m土层中硝态氮的计中状况结果表明:3年不施氮肥的土壤仍有6~16kg/hm2的硝态氮,其中0~20cm土层占20%~34%.80%~100cm上层占10%~18%;每季施氨量小于225kg/hm2时.1m上层中各时期硝态氮含量变化不大,在11.4~41.3kg/hm2之间;当施氮量增加到375kg/hm2时,1m土层的硝态氮含量增加1.5~7.4倍,有7.4%~29.9%分布在0~20cm上层中,10%~16%分布在80~100cm上层中225kg/hm2对作物斋求及对土壤环境来说是一个合理的施只量。
The field experiment was conducted to study the N content of nitrate nitrogen in 1m soil layer of wheat-corn rotation under different nitrogen rates and different periods. The results showed that there was still 6 ~ 16kg / hm2 Nitrate, of which 0 ~ 20cm soil layer accounted for 20% to 34%. 80% ~ 100cm upper layer accounted for 10% ~ 18%; quarterly ammonia consumption less than 225kg / hm2. The content of nitrate nitrogen in 1m upper layer changed little from 11.4 to 41.3kg / hm2. When the nitrogen application increased to 375kg / hm2, the nitrate nitrogen content in 1m soil increased 1.5 ~ 7.4 times, 7.4% ~ 29.9% distributed in 0 ~ 20cm upper layer, 10% ~ 16% distributed in 80 ~ 100cm upper layer 225kg / hm2 for crop fasting and the soil environment is a A reasonable amount of Shi.