Study On The Topdressing Model Of Nitrogen Nutrition Diagnosis Of Corn's Canopy Spectra

In our country, there are many problems on application of chemical fertilizer especially Nitrogen,suchas inefficient application,pollution to environment.In order to solve these problems,we must developprecision variable rate application,There are many achievements in research on control system of variable rate fertilizer applicator athome and abroad.In spite of good performance foreign system cost highly and is based on their countryown conditions,such as climate and soil so as to spread in our country is not suitable domesticpromotion.But domestic research and variable fertilization system has a problem about complex machineby the physical properties of fertilizer greater impact and the higher cost of the shortcomings.In recent years,remote sensing technology and the rapid development in precision agriculturedeepening of the application of near-Earth remote sensing variable fertilization test with the combinationpromoting the further development.A normalized difference vegetation index (NDVI) is the most importantcrop growth of the canopy structure parameters, has important implications in the light distributiongroups,energy use and crop yields.This article is mainly about Jilin Province in promoting soil testing process,the vast majority of farmerssuddenly changed the nitrogen-based corn,applying for a one-time use of fertilizer:it means that farmerscan not following the decision-making fertilization cards of nitrogen fertilizer application method(basal andtop dressing),instead of that they doing it in planting time with all nitrogen in the form of basal facilitiesinto the phenomenon.To bring fordward the application of corn nitrogen fertilizer should be applied in cropnutrition-based diagnosis system for topdressing fertilizer, The results based on NDVI values and corntopdressing model,access the immediate scene of corn under a canopy of normalized difference vegetativeindex point NDVI data analysis during the reproductive period of corn, come to the belt area optimalnitrogen content model (NFOA) parameters for local region of the corn.The results are:1.By using the deal without nitrogen fertilizer production in maturity stage and NDVI values without NDistrict during jointing stage to forecast corn yield potential model YP₀ (no N fertilizer yield): YP₀=0.5348e^{308.93(INSEY)}2.Use the highest yield divided by the value of variables NDVI topdressing District NDVI value can come to nitrogen response index model,the RI_NDVI average of variable topdressing nitrogen area ofdifferent treatment RI_N1=1.059(basal nitrogen quantity 14.66kg/hm²,topdressing nitrogen quantity29.33kg/hm²),RI_N2=1.081(basal nitrogen quantity 29.33kg/hm²,topdressing nitrogen quantity58.66kg/hm²),RI_N3=1.153 (basal nitrogen quantity 44kg/hm²,topdressing nitrogen quantity 88kg/hm²).3.By the yeild of without nitrogen fertilizer production (YP₀)during maturity stage and the results ofmodelâ‘¡to make the target yield (YP_N) model,the YP_M average of variable topdressing nitrogen area ofdifferent treatment, YP_N1=7.77Mg/hm²(basal nitrogen quantity 14.66kg/hm²,topdressing nitrogen quantity29.33kg/hm²),YP_N2=7.92Mg/hm²(basal nitrogen quantity 29.33kg/hm²,topdressing nitrogen quantity58.66kg/hm²),YP_N3=8.41Mg/hm² (basal nitrogen quantity 44kg/hm²,topdressing nitrogen quantity88kg/hm²).4.Using the maturity stage of the corn nitrogen uptake and the results of modelâ‘¢corn to containingN%of the average volume (PNG) model: PNG=1.8891-0.0463YP_NBy using PNG and the results of modelâ‘¢to calculate the gross of corn N uptake (GNUP),the gross of Nuptake average of variable topdressing nitrogen area GNUP_N1=102.619kg/hm²(basal nitrogen quantity14.66kg/hm²,topdressing nitrogen quantity 29.33kg/hm²),GNUP_N2=113.769kg/hm²(basal nitrogenquantity29.33kg/hm²,topdressing nitrogen quantity 58.66kg/hm²),GNUP_N3=137.117kg/hm² (basal nitrogenquantity 44kg/hm²,topdressing nitrogen quantity 88kg/hm²)5.Recover from the variable N district with not recover the value of NDVI and jointing stage cornplant nitrogen topdressing to calculated corn N uptake (FNUP) model: FUNP=19.217e^0.3077*NDVI6.Based on modelâ‘£and the results of⑤to caculate the current quarter nitrogen topdressingquantum model,the current quarter nitrogen topdressing quantum average of variable topdressing nitrogenarea FNR_N1=113.349kg/hm²(basal nitrogen quantity 14.66kg/hm²,topdressing nitrogen quantity29.33kg/hm²),FNR_N2=131.00kg/hm²(basal nitrogen quantity 29.33kg/hm²,topdressing nitrogen quantity58.66kg/hm²),FNR_N2=160.25kg/hm² basal nitrogen quantity 44kg/hm²,topdressing nitrogen quantity88kg/hm²).By achieving the parameters by optimal amount of nitrogen model (NFOA) will might be for thefuture using of GreenSeeker NIR sensor integrated into intertill fertilization machinery,laid the foundationto the development of real-time diagnosis of nutrition, decision-making, topdressing mechanicalvariable.Therefore we can simplifying the previous precision fertilization procedures,achieving the corn fertilizer largest nitrogen topdressing precision variable, have a significant to reduce nitrogen fertilizer andimprove the utilization of nitrogen fertilizer and improve the economic and environmental benefits.