本文选用喷灌施肥灌溉最常用的肥料—尿素，基于简易吸水法测量了不同尿素浓

In this paper, urea, which is the most commonly used fertilizer for sprinkler irrigation, was selected. Based on the simple water absorption method <br>, the amount of liquid fertilizer intercepted by the winter wheat canopy and the equivalent thickness of the plant attached fertilizer liquid at different urea concentrations (0~0.243%) and growth stages (joint-grouting) were measured. The effect of urea concentration on winter wheat canopy interception and adhesion was evaluated, and the following main conclusions were drawn: <br>(1) During the growth period of winter wheat, the amount of intercepted fertilizer liquid and the equivalent thickness of adhered fertilizer liquid vary with plant growth. The amount of intercepted liquid fertilizer has been increasing significantly with the growth of the plant. The average amount of intercepted liquid fertilizer in the canopy during the jointing and filling stage varies from 0.34 to 0.61 mm; the equivalent thickness of the attached fertilizer solution is both in the jointing and booting stage and the heading and filling stage. It shows a slight decrease trend with plant growth. The average thickness of attached fertilizer solution equivalent thickness varies from 0.051 to 0.080 mm during the first filling stage of jointing; the canopy intercepted fertilizer solution amount and attached fertilizer solution equivalent thickness are produced after winter wheat heading. Large increase, the maximum increase is 65% and 57% respectively. <br>(2) The effect of urea solution concentration on crop canopy storage capacity is closely related to the crop growth stage. When winter wheat enters the heading and jointing stages respectively, the canopy intercepted fertilizer amount and attached fertilizer equivalent thickness of different urea solution concentrations Significant differences occurred. When the fertilizer solution concentration was 0.092%, the canopy intercepted fertilizer solution reached the maximum 0.75 mm, and when the urea concentration was 0.162%, the attached fertilizer solution equivalent thickness reached the minimum 0.045 mm. <br>(3) There is a very significant linear positive correlation between the amount of liquid fertilizer intercepted by the canopy of winter wheat and the plant height, which can be used as a key index to evaluate the amount of liquid fertilizer intercepted by the canopy during sprinkler irrigation during the growth period of winter wheat; the equivalent of plant attached fertilizer liquid The thickness varies from -24% to 19% during the growth period of the crop. The average thickness of 0.067 mm and the plant density during the joint-filling period can be used to estimate the amount of liquid fertilizer intercepted by the canopy during the growth period of winter wheat.<br>In this paper, experimental data are used to obtain the influence of urea concentration on winter wheat canopy interception and adhesion. An effective model is selected to simulate the various influencing factors of the canopy during sprinkler irrigation, so as to improve the accuracy of the experimental data as much as possible. It effectively shows that different concentrations of canopy interception of fertilizer solution and the equivalent thickness of plant attachment fertilizer solution have significant effects on winter wheat. However, at the same time, there are still deficiencies in the experimental methods, and the impact mechanism and impact degree need to be further quantified by more advanced instruments and testing methods. For example, although the simple water absorption method used in this article has the advantages of cost saving, easy operation and short test period, on the one hand, because the test process is different from the actual sprinkler irrigation process, plant factors (leaf surface, plant type, flag leaf, Wheat ears, ground rebound, etc.), sprinkler irrigation technical elements (sprinkler model, spacing, installation height, spray intensity, atomization index, etc.) and meteorological factors (wind speed, temperature and humidity, etc.) The difference in the research results; on the other hand, because the method ignores the possible fertilizer volatilization loss when the fertilizer solution is sprayed from the nozzle to reach the crop canopy, it will affect the measurement accuracy of the canopy intercepted fertilizer.

In this paper, the most commonly used fertilizer for irrigation and fertilization, urea, was used to measure the concentration of different ureas based on the simple water absorption method<br>(0-0.243%) and the growth stage (pulling a grout) winter wheat canopy retention fertilizer volume and plant attachment fertilizer equivalent thickness, assessed the effect of urea concentration on winter wheat canopy retention and attachment capacity, and came to the following main conclusions:<br> (1) During the winter wheat fertility period, the amount of canopy retention fertilizer and the thickness of the attached fertilizer equivalent vary with the growth law of the plant, the amount of canopy retention fertilizer has been increasing significantly with the growth of the plant, and the average change range of the amount of canopy retention fertilizer during the irrigation period is 0.34 - 0.61 mm; the equivalent thickness of the attached fertilizer showed a slight decrease with the growth of the plant during the tug-of-pregnancy spike period and the spike grout period, and the average variation range of the adhesive fertilizer equivalent thickness during the irrigation period was 0.051-0.080 mm;The amount of fertilizer retained in the canopy and the equivalent thickness of the attached fertilizer produced a large increase after the winter wheat spike, with the maximum increase being 65% and 57%, respectively.<br> (2) The effect of urea solution concentration on crop canopy storage capacity is closely related to crop growth stage, when winter wheat enters the human spike period and the pull-out period respectively, the amount of canopy retention fertilizer and the thickness of the attached fertilizer equivalent of different urea solution concentrations are significantly different, when When the concentration of fertilizer is 0.092%, the amount of fertilizer retained in the canopy reaches a maximum of 0.75 mm, and when the concentration of urea is 0.162%, the equivalent thickness of the attached fertilizer reaches a minimum of 0.045 mm.<br>(3) There is a very significant linear positive correlation between the amount of winter wheat canopy retention fertilizer and the high plant height, which can be used as a key index to evaluate the amount of canopy retention fertilizer during the winter wheat fertility period;<br>In this paper, the influence of urea concentration on the retention and attachment ability of winter wheat canopy is obtained by experimental data, and an effective model is selected to simulate the various influence factors of the canopy during irrigation, so as to improve the accuracy of the experimental data as far as possible. It is effectively explained that the amount of canopy intercepting fertilizer at different concentrations and the yield thickness of plant attachment fertilizer will have a significant effect on winter wheat. However, at the same time, there are still some shortcomings in the experimental method, its influence factor and the degree of influence still need to be further quantified by more advanced instruments and test methods. For example, although the simple water absorption method used in this paper has the advantages of cost saving, easy operation and short test cycle, on the one hand, because the test process is different from the actual irrigation and fertilization process, ignoring plant factors (leaf surface, plant type, flag leaf, wheat spike, ground rebound, etc.), spraying technical elements (spray head model, spacing, installation height, spray intensity, atomization index, etc.) and meteorological factors (wind speed, temperature and humidity, etc.) On the other hand, because the method ignores the possible loss of fertilizer volatilization when fertilizer is sprayed from the nozzle to reach the crop canopy, it will affect the measurement accuracy of the amount of fertilizer retained in the canopy.

In this paper, urea, the most commonly used fertilizer for sprinkler irrigation, was selected to measure different urea concentrations based on the simple water absorption method<br>The effects of urea concentration on the canopy interception and adhesion capacity of winter wheat were evaluated at 0 ~ 0.243% and growth stages (jointing filling)<br>(1) During the growth period of winter wheat, the amount of intercepted fertilizer solution and the equivalent thickness of attached fertilizer solution varied with plant growth. The amount of intercepted fertilizer solution increased significantly with plant growth. The average value of intercepted fertilizer solution in canopy ranged from 0.34 mm to 0.61 mm during jointing filling stage; The average variation range of the equivalent thickness of the attached fertilizer was 0.051 ~ 0.080 mm during the jointing booting stage and heading filling stage. The amount of intercepted fertilizer solution and the equivalent thickness of attached fertilizer solution increased greatly after heading of winter wheat, and the maximum increase was 65% and 57%, respectively.<br>(2) The effect of urea solution concentration on crop canopy storage capacity is closely related to crop growth stage. When winter wheat enters heading stage and jointing stage respectively, the amount of intercepted fertilizer solution and equivalent thickness of attached fertilizer solution with different urea solution concentration have significant differences. When the concentration of urea solution is 0.092%, the amount of fertilizer intercepted by canopy reaches the maximum value of 0.75 When the urea concentration is 0.162%, the equivalent thickness of attached fertilizer solution reaches the minimum value of 0.045 mm.<br>(3) There was a significant linear positive correlation between the amount of fertilizer intercepted by the canopy and the plant height, which could be used as a key index to evaluate the amount of fertilizer intercepted by the canopy during the growth period of winter wheat; The variation range of the equivalent thickness of plant attached fertilizer solution was - 24% - 19% during the growth period of crops. The amount of fertilizer intercepted by the canopy during the growth period of winter wheat could be estimated by the average thickness of 0.067 mm and plant density during the growth period of winter wheat.<br>In this paper, the influence of urea concentration on canopy interception and adhesion capacity of winter wheat was obtained through experimental data. The effective model was selected to simulate the situation of various influencing factors in the process of sprinkler irrigation, so as to improve the accuracy of the experimental data as much as possible. The results showed that the amount of fertilizer intercepted by canopy and the equivalent thickness of fertilizer solution attached to plant had significant effects on winter wheat. But at the same time, there are still some deficiencies in the experimental methods, and its influence mechanism and degree need to be further quantified by more advanced instruments and testing methods. For example, although the simple water absorption method used in this paper has the advantages of saving cost, easy operation and short test cycle, on the one hand, because the test process is different from the actual spray irrigation and fertilization irrigation process, it ignores plant factors (leaf surface, plant type, flag leaf, wheat ear, ground rebound, etc.), sprinkler irrigation technical elements (nozzle type, spacing, installation height, spraying intensity, atomization index, etc.) and gas On the other hand, the method ignores the possible loss of fertilizer volatilization from the nozzle to the crop canopy, which will affect the measurement accuracy of the amount of fertilizer intercepted by the canopy.