| Aeolian sandy soil with low yields hinder maize growing in northwest Liaoning.Local farmers use fertilizer blindly in order to increase agricultural yield,resulting in lower irrigation and fertilizer efficiency.Drip irrigation fertilization is an efficient way to address efficient nutrient utilization,but research on drip irrigation irrigation-fertilization integrated nitrogen fertilization system for maize in aeolian sandy soil in northwest Liaoning is lacking in depth.As a result,this paper conducted nitrogen application amount,nitrogen application frequency,and nitrogen fertilization transport trials,with the following results:（1）The findings of N application trials revealed that increasing N application was advantageous to maize development（plant height,stalk thickness,and LAI）and considerably boosted WUE and yield under low irrigation conditions（W=0.6 KcET0）.Increasing N application enhanced the uniformity of soil nitrate-N distribution and improved soil fast-acting potassium content and uniformity but increased the risk of its transport to monopoly furrows.Under high irrigation conditions（W=1.0 KcET0）,increasing N application reduced the beneficial effects of irrigation on maize growth（plant height,stalk thickness,and LAI）and significantly reduced NPFP,resulting in yield reduction;increasing fertilizer application increased the nitrate N content of top soil but increased its distribution heterogeneity,and significantly increased the fast-acting potassium content of the profile but increased the downward gradient.Finally,for low irrigation,high N（300 kg/hm2）is indicated,while for high irrigation,low N（150 kg/m2）is recommended.（2）The results of the N application frequency test revealed that under low irrigation conditions,maize growth（plant height,stalk thickness,LAI,and SPAD values）and yield increased and then decreased with increasing N application frequency,with 7 fertilizer applications being the better;at jointing stage,fertilization 4 and 7 times raised the danger of nitrate nitrogen migration to ridges and ditches.Increased fertilization times raised the nitrate nitrogen content in the topsoil at the mature stage,but also increased the risk of nitrate leaching.The amount of accessible potassium and nitrate nitrogen in the soil were substantially associated with 11 fertilizer treatments.Increased nitrogen treatment periods are beneficial to maize growth（plant height,stem diameter,and LAI）under high irrigation conditions,but not to maize SPAD value improvement.It can improve several maize yield composition indexes and greatly increase yield,with a yield-increasing effect greater than that of low irrigation treatment;at the jointing stage,increasing fertilization times promotes nitrate nitrogen distribution near the root system.In the mature stage,1 and 2 fertilization times can enhance the content of accessible potassium,and the distribution of available potassium in 2 and 11 fertilization times corresponds to the root system.The levels of soil nitrate nitrogen and accessible potassium were strongly associated in the vertical direction on the 7 fertilization times treatments.Increased nitrogen application times are good for improving water and fertilizer utilization efficiency.In summary,it is recommended to apply nitrogen 7 times for low irrigation and 11 times for high irrigation.（3）The results of N fertilization transport trials research showed that,Nitrogen application at the ear and grain filling phases had a compensating effect on maize development,however concentrated fertilization at the jointing stage was not favourable to maize plant height and LAI growth（LAI and stem diameter）.The creation of dry matter of corn was aided by mass fertilization at the jointing stage,topdressing at the grain filling stage enhances the production of dry matter of grain,and the N4 treatment（heavy jointing fertilizer）had the highest NPFP,and yield.Concentrated and massive fertilization increased the uniformity of nitrate nitrogen distribution and the content of accessible potassium in the soil profile throughout the jointing stage,but it also raised the risk of nitrate nitrogen and available potassium downhill leaching.The amount of available potassium was increased,but so was the variability of its distribution and the risk of downward leaching;at full maturity,the distribution of available potassium in the N1（traditional fertilization）and N4（heavy jointing fertilizer）treatments was reasonable.On the horizontal N5（grain fertilizer）and vertical N3 treatments,the concentrations of soil nitrate nitrogen and accessible potassium were substantially associated（uniform fertilization）Nitrogen fertilizer management has a stronger early impact on maize plant height,less on stem diameter,and a clear impact on maize LAI under high watering conditions.Fertilization in the early stages of maize（seedling stage,jointing stage）was helpful to the creation of stem and leaf dry matter,and grain dry weight was also dominating in the later stages of maize.WUE,NPFP,and yield were highest in the N2 treatment（considering jointing and grain fertilizer）.Too much or too little nitrogen application rate during the jointing stage will cause an uneven distribution of nitrate content in the profile,and the downward leaching of nitrate nitrogen in high irrigation treatment was more noticeable than in low irrigation treatment.The levels of nitrate nitrogen and accessible potassium in the fertilizer profile rose during the grain filling period.The distribution of accessible potassium content in the N2 treatment profile was appropriate at full maturity.The levels of soil nitrate nitrogen and accessible potassium were substantially associated in the horizontal direction during N1 treatment（conventional fertilization）In conclusion for low irrigation water,N4 treatment is advised,and for high irrigation,N2 treatment is indicated. |
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