美国白蛾直升飞机防治中的雾滴分析及其对防治效果的影响

飞机防治是美国白蛾防控的最主要措施之一。为进一步明确飞行参数对林间雾滴密度分布和对美国白蛾幼虫防控效果的影响,该文通过检测、比较不同飞行方案下林间雾滴密度及雾滴穿透力等数据,发现航速和高度对林间喷幅、雾滴穿透力、雾滴密度、雾滴均匀度均产生显著影响。方案2(航速150 km/h,飞行高度40—45 m),地面喷幅宽度为59.35 m,高于方案1(航速120 km/h,飞行高度30—35 m)的地面喷幅宽度。飞行方案2的雾滴穿透性也相对较好,顶层、中层、下层雾滴密度相对均匀;而方案1不同高度雾滴密度差异相对较为显著,树冠顶层(高度11—12 m)雾滴密度较多,最高雾滴密度可达9.8/cm2,随高度降低,雾滴密度下降明显,到底层叶片位置(高度3 m)时,雾滴密度仅为2.07/cm2,下降了78.9%。观测试验表明,林间雾滴密度应高于5.093/cm2,防控效果才能确保达到90%。

Study on droplets and effect in controlling Hyphantria cunea by aerial spraying of helicopter

This paper deals with such a main control measure for Hyphantria cunea as spraying pesticide by plane.In order to further clarify the influence of flight parameters on droplet distribution and control effect,the density and penetration of fog droplets under different flight parameters were tested and compared.The results showed that the flight speed and height had significant effects on the spray width and the penetration,density and uniformity of droplets.Plan 2(speed 150 km/h,height 40—45 m)had a ground spray width of 59.35 m,higher than that of Plan 1(speed 120 km/h,height 30—35 m);The droplet penetration of Plan 2 was also relatively good,with the droplet density of the top layer,middle layer and lower layer relatively uniform.However,the droplet density at different heights in Plan1 was quite different,as droplet density was higher at 11—12 m,reaching 9.8/cm2,and with the decrease of height,the droplet density decreased obviously,but when reaching the bottom layer(3 m),the droplet density was only 2.07/cm2,decreased 78.9%.The control effect test suggested that droplet density should be higher than 5.093/cm2 to ensure the control effect of over 90%.