Research On Drip Irrigation Scheme Of Corn Field In Shihezi Area Based On Soil Water And Salt Transport

Submembrane drip irrigation technology has the advantages of concentrating available water and nutrients,improving water utilization efficiency,inhibiting soil water evaporation,and inhibiting soil salt surface aggregation.Based on the HYDRUS-2D software,the migration process of soil water and salt during the growth period of summer maize under different irrigation conditions and different film mulching conditions was simulated,and the appropriate maize irrigation system was put forward in Shihezi area.It provides scientific reference for improvement of crop planting scheme and soil salinization control in the future.The main conclusions are as follows:(1)Through field experiments and data analysis,the distribution law of soil water and salt under different irrigation schemes was studied.After the comparison,it is concluded that the 4800m3/hm2 irrigation scheme has a better effect on the water replenishment and desalination of the soil in the corn root-intensive area during the field planting process of corn.Provide reference for corn planting in Shihezi area.(2)HYDRUS-2D software was used to conduct numerical simulation of soil water and salt migration under drip irrigation in 2019,and to verify the reliability of the established numerical model.The results showed that the correlation coefficient between simulated soil moisture content and measured soil moisture content ranged from 0.385 to 0.744,and the root mean square error ranged from 0.025 to 0.069.The correlation coefficient between simulated soil moisture content and measured soil salt content ranged from 0.959 to 0.991.The HYDRUS-2D model provides an accurate and reliable numerical simulation of corn field irrigation.(3)Irrigation simulation was carried out for maize growth period,and soil water and salt transport laws under different mulching schemes were analyzed.The results showed that with the increase of film mulching length,the rainfall infiltration and recharge of soil evaporation and resalting crane would be inhibited.When 70cm film mulching scheme was adopted,the volume water content of each layer of soil could be kept at a higher position,and the change of water content was more stable,which was beneficial to the water absorption of roots.At the same time,under the 70cm film mulching scheme,the soil salt content in the irrigation process generally presents a downward trend,and the soil salt content keeps decreasing,and the salt is mainly concentrated in the deep soil and the bare land outside the film.Rainfall and irrigation can play an obvious effect of salt flushing on the soil,and the crop growth is less affected by the inhibition effect of high salt area.In the soil layer of 10-35cm with dense root distribution,light salt zone was formed,which was beneficial to crop development.Therefore,when the irrigation amount is constant,the70cm film mulching scheme can enhance soil water holding capacity and reduce soil salt content,which is conducive to the growth of maize and increase its yield.(4)Irrigation simulation was carried out for maize growth period,and soil water and salt transport laws were analyzed under different irrigation schemes.The results showed that when 4400m~3/hm~2irrigation scheme was adopted,the volumetric water content of each soil layer was in a higher position,and the irrigation efficiency was higher than that under higher irrigation amount,which was beneficial to the growth of maize.At the same time,with the increase of irrigation amount,soil salt content generally decreases,and when irrigation amount reaches 4800m~3/hm~2,irrigation amount will no longer have a dominant effect on soil salt distribution.Therefore,the application of 4800m~3/hm~2irrigation scheme in maize planting can effectively improve water use efficiency,slow down salt accumulation in maize root zone,and prevent soil salinization.