施氮量及间作对燕麦、向日葵生产力及土壤硝态氮累积的影响

Effects of nitrogen application rate and intercropping on oat and sunflower productivity and soil nitrate accumulation

为研究不同施氮量及间作对燕麦、向日葵生产力以及燕麦收获后土壤硝态氮累积量的影响,在吉林西部半干旱地区开展大田试验,设置不同施氮量处理(0、50和100kg/hm2),测定燕麦、向日葵产量、吸氮量及土壤硝态氮含量。结果表明:燕麦‖向日葵带状间作具有产量优势及较高的氮吸收效率,土地当量比及氮素吸收当量比范围分别为1.20~1.37和1.20~1.30。施氮量为100kg/hm2时,间作燕麦、向日葵籽粒产量、地上部生物量以及地上部吸氮量均为最高,分别为4.40和6.65t/hm2,12.81和12.40t/hm2以及182.78和192.12kg/hm2,其中间作燕麦地上部生物量、吸氮量较单作燕麦显著提高17.20%~35.39%;间作向日葵籽粒产量及地上部吸氮量较单作向日葵显著提高22.78%~46.15%。间作显著降低燕麦收获后间作燕麦边行0~60cm土壤硝态氮累积量,显著增加间作向日葵边行土壤硝态氮累积量。因此,100kg/hm2是该地区燕麦‖向日葵带状间作的较优施氮量。

In order to investigate the effects of different nitrogen application rates and intercropping on oat,sunflower productivity and nitrate accumulation after oat harvest,a field experiment was conducted in semi-arid regions of western Jilin province with 3 nitrogen application rates （0,50,and 100 kg/hm^2）.Yield,nitrogen uptake and soil nitrate content were measured.The results showed that：Oat and sunflower strip intercropping had yield advantages and higher N uptake efficiency.Its land equivalent ratio （LER） and N uptake equivalent ratio （NER） were ranged from 1.20-1.37 and 1.20-1.30 respectively;at 100 kg/hm^2 N application rate,intercropped oat and sunflower had the highest seed yield （4.40 and 6.65 t/hm^2）,above ground biomass （12.81 and 12.40 t/hm^2） and N uptake （182.78 and 192.12 kg/hm^2）.The aboveground biomass and N uptake for intercropped oat was increased by 17.2%-35.4% compared to sole oat while the yield and N uptake for intercropped sunflower was increased by 22.78%-46.15% compare to sole sunflower.Intercropping significantly decreased soil （0-60 cm） nitrate nitrogen accumulation in the border rows of intercropped oat after oat harvest,however,it significantly increased soil nitrate nitrogen accumulation in the border rows of intercropped sunflower.Overall,it was found that 100 kg/hm^2 nitrogen application rate was optimal for oat and sunflower strip intercropping in this region.