旱地冬小麦氮磷自然供给能力及其吸收氮磷来源的长期定位试验

Study on N,P natural supplying capacity and their source absorbed by winter wheat in arid highland under long-term fertilization conditions

利用在黄土旱塬上布置的 13年小麦连作肥料定位试验资料 ,研究了旱地冬小麦氮磷的自然供给能力和吸收来源于肥料和土壤的氮磷相对比例。结果表明 ,旱地冬小麦氮素的自然供给能力为 2 6 6 8～ 2 7 4 9kg/hm2 ,平均为 2 7 2kg/hm2 ;磷素自然供给能力为 5 2 1～ 8 4 9kg/hm2 ,平均为 7 31kg/hm2 。小麦吸收氮素有 51 9%～ 76 8%来自氮肥 ,平均为 6 6 6 % ;而来自土壤为2 3 2 %～ 4 8 1% ,平均 33 4 %。小麦吸收磷素来源于肥料的为 13 6 %～ 4 7 8% ,平均为2 8 7% ;来源于土壤为 52 2 %～ 86 4 % ,平均为 71 3%。同一肥底基础上 ,随肥料用量的增加 ,小麦吸收氮或磷素来源于肥料的比例也增大 ,而来源于土壤的比例逐渐减少。本试验条件下 ,氮肥利用率变幅为 32 6 %～ 6 6 0 % ,平均为 51 1% ;磷肥利用率变幅为 1 72 %～ 14 0 2 % ,平均为 7 0 %

The paper studies N,P natural supplying capacity and their source ratio absorbed from soil and fertilizer by winter wheat in Changwu arid highland with 13 years position fertilization experiment of wheat continuous crop system The results showed that N natural supplying capacity was 26 68～27 49 kg/hm 2, average 27 2 kg/hm 2 and P natural supplying capacity was 5 21～8 49 kg/hm 2, average 7 31 kg/hm 2 Wheat absorbed N from nitrogen fertilizer in 51 9%～76 8%, average 66 6% and the rest from soil Wheat absorbed P from phosphate in 13 6%～47 8%, average 28 7% and the rest from soil On the same fertilizer base, wheat absorbed N,P ratio from fertilizer increased with N,P supplying rates N use efficiency was 32 6%～66 0%, average 51 1%, and P use efficiency was 1 72%～14 02%, average 7 0% under the experiment conditions