不同管理模式对春玉米土壤硝态氮累积与氮素利用率的影响

摘要

The effects of different management patterns(Control treatment /CK,Farmer practice treatment /FP, Optimized application treatment /OPT,High yield and high efficiency treatment /HY),nitrate nitrogen accumulation, nitrogen balance and use efficiency in 3 sites(WS,QX,DY)with different soil fertilities (high,mid,low).The re-sults of three-year field experiments showed that the nitrate nitrogen accumulations decreased in the order:FP >HY >OPT >CK in 0 -200 cm soil profiles,at the harvest stage(201 1 ,2012)of spring maize in 3 sites.The highest nitrate nitrogen residue average was 287.7 kg /ha at the site of WS,respectively 18.4% and 1 1 .6% higher com-pared with the site of DY and QX.The nitrogen apparent losses were the highest from FP,which were FP >HY >OPT >CK in 3 sites,except the CK treatment.The crop uptake decreased as HY >OPT >FP >CK at all the sites. Nitrogen agronomic use efficiency decreased as HY >OPT >FP(201 1 ,2012),the highest nitrogen recovery efficien-cy was HY(67.6%)at the site of QX(2013).The residue mineral N and nitrogen apparent losses were influenced by soil fertilities,whereas nitrogen utilization were no significantly with soil fertilities.It was suggested that the pat-tern like HY with controlled N application rate and increasing organic fertilizer should be generalized,to reduce ni-trate nitrogen residue and improve N use efficiency.%在高肥力（文水）、中肥力（祁县）、低肥力（东阳）条件下，研究了不同管理模式（无氮肥对照、农户习惯、优化处理、高产高效处理）对春玉米土壤剖面硝态氮分布、累积与氮素平衡以及氮肥利用率的影响。通过3年定位试验，结果表明，春玉米收获后0～200 cm 土壤剖面硝态氮累积量，在2011，2012年3个试验点都表现为：农户习惯＞高产高效＞优化处理＞无氮对照。文水试验点硝态氮累积量最高，三季平均为287．7 kg ／hm 2，比东阳和祁县土壤硝态氮累积量分别高18．4％和11．6％。氮素表观损失在3个肥力水平都均表现为农户习惯＞高产高效＞优化处理＞无氮对照。作物携出量在3个肥力水平均表现为：高产高效＞优化处理＞农户习惯＞无氮对照。在2011，2012年氮素农学利用率均表现为：高产高效 处 理＞优化处理＞农户习惯，2013年氮素回收率最高为祁县。高产高效处理达67．6％。通过合理的管理模式，可以在提高产量的同时显著提高氮素的利用率，并降低土壤中硝态氮的残留量。