Study On The Mechanism And Control System Of Maize Aerated Percolation Irrigation To Increase Yield

Aerated infiltration irrigation technology is based on the infiltration irrigation technology,using Roots fans and other ventilation devices to add air to the crop root soil to achieve effective regulation of soil moisture and gas content in the crop root zone.Previous studies have shown that aerated infiltration technology can significantly improve the soil environment in the root zone of crops and enhance crop yield and quality.However,the research on the mechanism of crop yield increase under aerated infiltration technology is not deep enough,and how to optimize the technical parameters of aerated infiltration to improve the crop yield in stages is the next research focus.In order to find out the influence of air infiltration technology on soil environment and crop growth,and to analyze the mechanism and regulation path of crop quality and yield increase under air infiltration technology.In this study,we conducted a field experiment of aerated infiltration irrigation technology based on the theoretical basis of the contradiction of soil oxygen supply and consumption:1.0),aerated volume A（A₁:V/time;A₂:2V/time;A₃:3V/time）and aerated period T（T₁:06:00-08:00;T₂:14:00-16:00;T₃:20:00-22:00）were selected as influencing factors to monitor and investigate the response of soil environment and crop growth in the root zone to different technical parameters of aerated infiltration at different fertility periods of maize.By constructing a soil-crop growth structural equation model,we further elaborated the improvement mechanism and pathway of maize yield increase under aerated infiltration technology,and finally derived the suitable combination of aerated infiltration technical parameters for different fertility periods of maize based on principal component analysis,and combined with intelligent control technology to realize the intelligent development of aerated infiltration technology.The main contents are as follows:（1）A conceptual model of soil oxygen transport was constructed based on crop physiology and soil physical processes,and validated by three environments:field irrigation,field fertilization and extreme rainfall.The changes of soil oxygen content,water content and soil respiration rate under aerated infiltration technology were quantitatively analyzed with traditional infiltration technology as a control.The study results showed that the aerated infiltration technology can alleviate the tendency of soil oxygen content decreasing due to field irrigation,field fertilization and heavy rainfall,and ensure that the minimum value of soil oxygen content is not too low,which can ensure the normal soil environment required for crop survival.This reveals the effect of artificial aeration and oxygenation on improving the soil environment and promoting crop growth.（2）The results showed that the aerated infiltration treatments had significant（P<0.05）or highly significant（P<0.01）effects on soil respiration rate,soil oxygen content,soil bacterial biomass,urease activity,catalase activity,and phosphatase activity during the nodulation-maturation and maturation stages of maize.0.01).The structural equation model constructed with soil environmental indicators for the improvement of soil aeration and soil fertility systems by aerated infiltration irrigation technology showed that aerated volume had a strong positive effect on both soil fertility（path coefficient of 0.784,P<0.05）and soil aeration（path coefficient of 0.770,P<0.01）.（3）Based on the investigation of the improvement of soil environment in the root zone by aerated infiltration technology,the effect of aerated infiltration technology on root growth of maize at different reproductive stages was further analyzed.Root length,root surface area,root volume and root dry weight in treatment W₃A₃T₂were significantly（P<0.05）and highly（P<0.01）higher than those in the control treatment during the maize tasseling stage-filling stage.The analysis based on the soil environment-root growth structural equation model showed that soil aeration and soil fertility had a significant positive effect on root indexes,and the effect of aerated infiltration irrigation technology was in descending order of aerated volume>irrigation level>aerated period,and the improvement path of aerated volume→soil fertility→root growth（path coefficient of 0.381）was the key path to improve maize root growth.（4）The aerated infiltration technology improved the growth and development of above-ground parts of maize based on improving the soil environment in the root zone and promoting root growth.The results showed that the aerated infiltration technology had no significant effect on the early and late stages of maize,but it could promote the rapid growth of plant height and stalk thickness during the nodulation-emergence stage and the male-emergence-irrigation stage,and had significant（P<0.05）or highly significant（P<0.01）positive effects on photosynthetic rate,transpiration rate,stomatal conductance and chlorophyll content.Analysis of the soil environment-maize growth structural equation model showed that the aerated infiltration technology had a strong positive effect on yield via soil fertility and root system indicators with a path coefficient of 0.455（P<0.01）;therefore,the improvement of soil fertility in the root zone and the consequent enhancement of maize root growth by aerated infiltration technology was the key to yield improvement.（5）Based on a comprehensive analysis of the differences in the effects of different treatments on the three types of indicators characterizing maize growth（soil environment,root growth,and crop growth）,the combined scores of each treatment were obtained by principal component analysis.The treatment with the highest score at the seedling-pulling stage of maize was W₁A₃T₃,the treatment with the highest score at the pulling stage of maize-tasseling stage was W₂A₃T₁,the treatment with the highest score at the tasseling stage of maize-filling stage was W₃A₃T₂,and the treatment with the highest score at the filling stage of maize-maturity row was W₃A₃T₂.（6）Based on the suitable parameters of aerated infiltration irrigation for different fertility periods of maize,the integrated control system of aerated infiltration irrigation in the field was constructed,and the main structure was designed and selected,the equipment was controlled by PLC as the core,the system verification and operation test showed that the operation of all parts was stable,and the field application effect showed that the maize yield was significantly increased by 20.51%（P<0.01）compared with the traditional infiltration irrigation technology,the research results The results of the study provide a theoretical basis for the practical application of aerated percolation technology in different fertility periods of the crop.