覆盖旱作方式和施氮水平对稻-麦轮作体系生产力和氮素利用的影响  

Effects of non-flooded mulching cultivation and N rates on productivity and N utilization in rice-wheatcropping systems

作　　者：范明生[1] 刘学军[1] 江荣风[1] 张福锁[1] 吕世华[2] 曾祥忠[2] 

机构地区：[1]中国农业大学植物营养系 [2]四川省农科院土肥所,成都610066

出　　处：《生态学报》2004年第11期2591-2596,共6页Acta Ecologica Sinica

基　　金：国家重大基础规划资助项目 ( 19990 1170 7) ;教育部重大资助项目 ( 0 112 ) ;国家自然科学基金重大资助项目 ( 3 0 3 90 0 80 )~~

摘　　要：在成都平原通过 3a的田间试验研究了水稻覆盖 (地膜和麦秸 )旱作和施氮水平对稻麦轮作体系生产力和氮素利用的影响。结果表明 :在施氮量为水稻季 15 0 kg/hm2 ,小麦季 12 0 kg/hm2 的条件下 ,覆盖旱作和传统淹水体系均能达到较高的产量水平。再增加施氮量对产量的影响不大 ,但使氮盈余急剧增加。不施氮或低量施氮会造成作物产量的显著下降和土壤氮素亏缺。水稻覆膜旱作对稻麦轮作的系统生产力 (水稻 +小麦 )没有显著影响 ;但水稻覆麦秸旱作条件下系统的生产力有降低的趋势 ,主要由于水稻覆麦秸旱作条件下 ,水稻产量下降 ,而麦秸覆盖在小麦季的后效作用不足以弥补水稻产量的下降程度。水稻、小麦的氮素吸收表现出与作物产量类似的规律。水稻季土壤很难累积无机氮 ,而且与施肥和覆盖旱作与否没有关系。小麦季土壤中积累了较多的无机氮 。Non- flooded mulching rice cultivation has been adopted and developed as a new water- saving cultivation technique in many regions of China since the late1980 s.But information on the effects of non- flooded mulching cultivation of rice on the productivity and sustainability of rice- wheat cropping systems is still lim ited.A unique feature of lowland rice- upland winter wheat systems is the annual conversion of soil from aerobic to anaerobic and then back to aerobic conditions. Non- flooded mulching cultivation alters the rice growth environmentthrough changes in soil water condition and leads to a prolonged aerobic phase in rice- wheat cropping systems.That causes a difficulty to conserve soil organic matter and soil nitrogen in the cropping systems,and therefore maybe affects productivity and sustainability of such cropping systems. Additionally,N managem ent of cropping system s is the other issue thatis im portant to agricultural sustainability.The changes in soil hydrological status from anaerobic(traditional flooding) to aerobic(non- flooded mulching) will largely affect the N forms and even N availability in soil.It is essential to exam ine the effects of non- flooded mulching cultivation on the N utilization and the N balance in rice- wheat cropping systems. A field experiment was conducted to determine the effects of non- flooded mulching rice cultivation and different Napplication rates on the productivity and N utilization in rice- wheat cropping systems of the Chengdu plain in southwest China over a 3- year period. The experim ent included three cultivation system s:TF(traditional flooding system ) ,PM (plastic film mulching system ) and SM (wheat straw mulching system ) during rice seasons,and zero tillage cultivation during wheat seasons;and four N application rates:N0 (0 kg N/ hm2 to both rice and wheat) ,N1(75 kg N/ hm2 to rice and6 0 kg N/ hm2 to wheat) ,N2 (15 0 kg N/ hm2 to rice and12 0 kg N/ hm2 to wheat) ,and N3(2 2 5 kg N/ hm2 to rice and180 kg N/ hm2 to wheat) . All treatme

关 键 词：水稻-小麦轮作 覆盖旱作 氮肥 氮素平衡 无机氮残留 秸秆利用 

分 类 号：S158[农业科学—土壤学]