Effects Of Nitrogen Application Rate And Planting Structure On Characteristics Of Nitrogen Use In Maize/pea Intercropping

According to the disordered planting structre,nitrogen application system backward ofcereal/legume intercropping in Hexi oasis irrigation area. Take maize/pea intercropping asrepresentative,a field experiment was carried out to investigate the effects of differentnitrogen application（N1,N2,N3） and planting structure（2:4,3:4） on Spatio-temporaldynamics of soil nitrogen, fertilizer use efficiency of maize/pea and yield, to expose themechanismof correlation between Spatio-temporal dynamics of soil nitrogen, provide atheoretical basis for scientific establishment of maize/pea intercropping syetem andefficient nitrogen management in Hexi Oasis Irrigation.The main results showed asfollowing:1. The planting structre significantly affect Soil NO₃⁺-N、NH₄⁺-N and total nitrogencontent of0-30cm soil layer, soil NO-3-N, NH+4-N of0-30cm soil layer in Monoculturemaize>2:4maize/pea intercropping> Monoculture pea>3:4maize/pea intercropping,soil totalnitrogen of intercropping system20-30cm soil layer>Monoculture pea and maize.2. Soil NO₃⁺-N、NH₄⁺-N and total nitrogen content of monoculture pea、 monoculturemaize、2:4maize/pea intercropping、3:4maize/pea increase as the increase of nitrogenapplication, Soil NO-3-N was increased by73.71%、83、18%、64.93%、52.97%、87.05%、86、18%、81.93%、83.52%than it at N2and N3nitrogen applications.3. there are nitrogen concentration gradient between the two bands of intercroppingsystems.In3:4intercropping system Soil NO-3-N and total nitrogen of corn belt0-30cm soilprofile is higher than the pea belt, NH+4-N of peas belt0-30cm soil profile is higher than thecorn belt.4. Two rows of maize intercropped with four rows of pea （2:4） was more beneficial toincrease LER, the LER of2:4intercropping was increased by6.7%、14.8%than3:4intercropping at N2and N3nitrogen applications, the LER of intercropping increased withthe increase of nitrogen application, but the increase of intercropping was weaken whennitrogen application beyond a certain level. The yield of2:4maize/pea intercropping>monoculture maize>3:4intercropping>monoculture pea, and the yield of different treatmentwith the increase of nitrogen application, the2:4maize/pea intercropping system can beused as one of the best intercropping systems for Hexi oasis irrigation areas now. 5.2:4maize/pea intercropping increase nitrogen use efficiency significantly. thenitrogen use efficiency of2:4intercropping was increased by81.97%、83.79%、48.56%than3:4intercropping at N2nitrogen applications, increased by67.72%、98.54%、40.32%than3:4intercropping at N3nitrogen applications. It shows the2:4maize/pea intercropping systemat N2nitrogen application can be used as one of the best nutrient absorption and use optimalintercropping system.6. The nitrogen use efficiency and economic yield were positive with nitrogenabsorption, soil nitrogen content and nitrogen application, the nitrogen use efficiency weresignificantly negative with SNDR, so increasing the nitrate content of soil by the efficientmanagement of nitrogen fertilizer in maize/pea intercropping pattern, and timely regulation,is one of the mechanisms of Saving fertilizer and high yield in maize/pea intercroppingsystem.