寒地玉米植保无人机航空施药雾滴沉积效果研究

Droplet Deposition Effectiveness of Plant Protection UAV Aerial Application on Corn in Cold Region

作为智能农业的重要组成部分,植保无人机的使用大大提高了作业效率,但智能设备快速推广使用的同时也对环境产生了一定的风险及危害。为了实际检测植保无人机的喷施效果并评估施药风险,开展北方寒地玉米多旋翼植保无人机航空喷雾效果研究,着重对比3种不同施药量下雾滴在玉米冠层不同部位的沉积效果,同时就添加助剂对于雾滴沉积的影响效果进行分析。结果表明:自然风对雾滴沉积效果的影响程度要强于施药量的变化,尤其是当无人机使用孔口尺寸较小的常规压力喷头进行喷施作业时,若自然风风速较大会显著导致无人机有效沉积减少(p=0.045);在2m的喷施作业高度下,施药量为15L·hm^(-2)(1#、4#)和30L·hm^(-2)(2#)时雾滴沉积效果的差异并不是很大。只有当施药量增大为45L·hm^(-2)时,才可以在一定程度上增加喷施雾滴在玉米冠层间的沉积,但会导致雾滴的沉积均匀性变差以及沉积率降低,污染环境的风险也随之加大。研究还发现添加助剂会使航空喷施雾滴粒径显著增大,对于雾滴覆盖率和沉积密度的沉积分布效果也有一定影响作用,却并不显著。研究结果可以作为当前植保无人机施药作业的参考。

As an important component of intelligent agriculture,the use of intelligent plant protection unmanned aerial vehicle(UAV)greatly facilitates agricultural production,effectively reduces resource consumption and improves operational efficiency.However,the rapid development and use of smart equipment also bring potential risks and harm to the environment which should be noticed.In order to detect the spraying effect of intelligent plant protection UAV and assess the risk of pesticide application,this paper carried out an experiment on the droplet deposition effectivenss of multi-rotor plant protection UAV spraying corn in the north cold region.This experiment mainly compared the deposition effects of droplets on different positions of the corn canopy under three application rates,and explored the effects of additives on the droplets deposition.The results showed that when the drone used a nozzle with a smaller orifice size for spraying operations,if the natural wind speed was strong,the increase in the spray amount may not significantly increase the effective droplets deposited amount.And the impact of natural wind on the droplet deposition effectivenss was stronger than the change of spray rate,a larger wind speed would result in a significant decrease in the effective deposition(p=0.045).Under the application height of 2m, there was not much difference in the droplet deposition effectiveness when the application rate was 15L· hm^(-2) (1#, 4#) and 30L·hm^(-2) (2#), but the difference of the droplet deposition effectiveness between the two and when the application rate was 45L·hm^(-2) (3#) was more obvious. At the same time, when the application rate increased from 15L·hm^(-2) to 45L·hm^(-2), the droplet deposition uniformity would also become worse, and the droplet deposition rate would also decrease. The addition of additives would significantly increase the droplets size. In the case of the same application rate, the treatment of droplets with no additives in the droplets size range of less than 150μm was much higher than the treatment of droplets with additives. For the deposition effectiveness of droplet coverage and deposition density, the use of additives had a certain influence, but it was not significant. The uniformity of the overall deposition distribution of each treatment was in the range of 90.68% to 149.96%, and the penetrability was in the range of 19.22% to 73.48%. In the future, it is necessary to strengthen the research work on the uniformity and penetration of droplet deposition. The research results could provide references for the current pesticide application operations of intelligent plant protection UAV.