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A wind tunnel study was conducted to determine pesticide deposition on commonly used windbreak tree species used as spray drift barriers and associated exposure of honey bees. Although it has been known that windbreaks are effective in reducing chemical drift from agricultural applications, there is still an enormous information and data gap on details of the dependence of the mechanism on the biological materials of the barriers and on standardization of relevant assessment methods. Beneficial arthropods like honey bees are adversely affected by airborne drift of pesticides. A study was initiated by first establishing a wind tunnel to create a controlled environment for capture efficiency work. Suitable spray parameters were determined after a preliminary study to construct and develop a wind tunnel protocol. A tracer dye solution was sprayed onto the windbreak samples and honey bees located in the wind tunnel at various simulated wind speeds. Analysis of data from this work has shown that needle-like foliage of windbreak trees captures two to four times more spray than broad-leaves. In addition, it was determined that, at lower wind speeds, flying bees tend to capture slightly more spray than bees at rest. 相似文献
3.
植保无人机施药沉积飘移监测系统设计与应用 总被引：1，自引：0，他引：1
为提升植保无人机施药沉积飘移监测智能化水平,研发植保无人机施药沉积飘移监测系统,该系统机载监测终端实时获取药械状态参数、植保无人机状态参数及位置参数,通过数据处理服务系统将其发送至平台软件,基于作业参数利用沉积飘移预测模型实时监测药液沉积区域及飘移范围。该系统同时具有作业面积计量、飞行轨迹回溯、作业质量空间分析等功能。2015年4月于山东省威海市文登区泽头镇眠虎岭区域对该系统进行性能测试,植保无人机规划靶区作业面积为433 hm2,最终监测作业面积为405 hm2,施药覆盖率为93.5%;施药过程中实时监测沉积区域和飘移范围,受环境侧风影响,药液最大飘移距离可达40 m,系统整体达到预期设计要求。截至目前该系统已在山东、安徽、江苏、云南、河南、浙江、天津等多个省市应用。 相似文献
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Background
Pesticide spray drift, which is the movement of pesticide by wind to any location other than the intended area, is hazardous to human, animal, food safety and environmental health. It is not possible to completely eliminate spray drift during spraying with field crop sprayers, but spray drift can be reduced by developing new technologies. The most common methods to reduce spray drift are carrying the droplets to the target with air-assisted spraying, electrostatic spraying, preferring air induction nozzles and boom shields. With these methods, it is not possible to make a change on the sprayer depending on the wind intensity during spraying. In this study, a novel servo-controlled spraying system was designed and developed to change the nozzle orientation angle in the reverse direction of the wind current to reduce the ground spray drift in real time and automatically in a wind tunnel. The displacement in the spray pattern (Dc) was used as a ground drift indicator for each nozzle to evaluate the spray drift.Results
The developed system, operated by LabVIEW software, calculated different nozzle orientation angles depending on nozzle types, wind velocities and spraying pressures. Orientation angles calculated for different test conditions achieved in reduction were up to 49.01% for XR11002 nozzle, 32.82% for AIXR11002 nozzle and 32.31% for TTJ6011002 nozzle at 400 kPa spray pressure and 2.5 m s−1 wind velocity.Conclusion
The developed system, which has a self-decision mechanism, calculated the nozzle orientation angle instantaneously according to the wind velocity. It has been observed that the adjustable spraying nozzle system, sprayed with high precision towards the wind in the wind tunnel, and the developed system have advantages compared to conventional spraying systems. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. 相似文献5.
Spiders are important arthropod predators in natural and agricultural environments. This laboratory study aims to determine the uptake of agrochemical spray by orb webs. Orbs of Araneus diadematus were exposed under controlled conditions to sprays of variable pressure, volume, forward speed and droplet size. Using a tracer dye we determined, by photospectrometry, the amount of spray collected under different conditions which enabled us to calculate the exact volume collected by webs. The spraying treatment simulated four different field practices as well as drift to the field edge. In all cases webs were excellent collectors of spray. Regarding the pure area of the threads, they collected one order of magnitude more of the spray than paper strips did. Moreover, webs were especially efficient in collecting small droplets. We conclude that orb webs (and the spiders who ingest them) are severely exposed to agricultural sprays. Furthermore, due to the uptake of drift, even webs in hedgerows and at field margins may receive high levels of pesticides. The risk of exposing these beneficial arthropods to spray might be reduced by better control of droplet size. 相似文献
6.
Effects of sand-fixing and windbreak forests on wind flow: a synthesis of results from field experiments and numerical simulations 总被引：1，自引：0，他引：1
Kejie ZHAN 《干旱区科学》2017,9(1):1-12
Sand-fixing and windbreak forests are widely used to protect or/and improve the ecological environments in arid and semi-arid regions. A full understanding of wind flow characteristics is essential to arranging the patterns of these protective forests for enhancing the effectiveness. In this study, the wind velocity over the underlying surface with sand-fixing forests and windbreak forests at the heights of 1–49 m was monitored from two 50-m high observation towers in an oasis of Minqin, Gansu Province of China. The wind velocities were simulated at different locations over these protective forests between those two towers by a two-dimensional Computational Fluid Dynamics(CFD) model. The results showed that at the heights of 1–49 m, the wind velocity profiles followed a classical logarithm law at the edge of the oasis and a multilayer structure inside the oasis. With increasing number of sand-fixing forest and windbreak forest arrays, the wind velocity at the heights of 1–49 m generally decreased along the downstream direction of the prevailing wind. Specifically, below the height of windbreak forests, the wind velocity decelerates as the airflow approaches to the windbreak forests and then accelerates as the airflow passes over the windbreak forests. In contrast, above the height of windbreak forests, the wind velocity accelerates as the airflow approaches to the windbreak forests and then generally decelerates as the airflow passes over the windbreak forests. Both the array number and array spacing of sand-fixing and windbreak forests could influence the wind velocity. The wind protection effects of sand-fixing forests were closely related to the array spacing of windbreak forests and increased with the addition of sand-fixing forests when the array of the forests was adequately spaced. However, if the array spacing of windbreak forests was smaller than seven times of the heights of windbreak forests, the effects were reduced or completely masked by the effects of windbreak forests. The results could offer theoretical guidelines on how to systematically arrange the patterns of sand-fixing and windbreak forests for preventing wind erosion in the most convenient and the cheapest ways. 相似文献
7.
R. MERRETT 《EPPO Bulletin》1983,13(3):413-417
Chemical desiccation with Regione (diquat) of oilseed crops prior to harvesting is now a well established farming practice. The many varied practical (and economic) advantages give the farmer more flexibility and control in planning his operations at a particularly busy time of year. However, desiccants are not selective of green plant tissue, so it is important that the spray is confined to the target crop. Spray drift is not normally a problem with ground spraying, but with aerial application particular care in the selection of equipment, flying technique, and climatic conditions is essential. This is particularly important when desiccating early maturing crops, such as oil-seed rape, when other crops, for example sugar beet and maize, are still green and growing. The potential spray drift risk can be reduced by planting similar crops in large blocks rather than in fragmented strips throughout the farm. By restricting the length of spray boom on the aircraft, using efficient diaphragm shut-off nozzles angled rearwards to the airstream, fitted with nozzles such as spraying Systems D8 or 10 with 46 or 56 swirl plates operating at maximum pressure of 2 bar, much of the drift hazard resulting from the equipment can be reduced. It is essential that the spray is turned on/off only in level flight and that the height of the spray boom above the top of the crop is less than 2.5 m. Spraying should only be carried out in wind speeds of 1-4 m/s and never under temperature inversion conditions. Large helicopters should only be used discriminately in very large areas of crop. 相似文献
8.
风洞环境下喷头及助剂对植保无人飞机喷雾飘移性的影响 总被引：2，自引：0，他引：2
为探究和减少植保无人飞机喷雾施药过程中的雾滴飘移,采用由单个旋翼与喷头组成的喷雾单元,在可控风洞环境条件下进行了模拟飞行喷雾试验,控制风洞条件为风速5 m/s、喷雾压力0.3 MPa及旋翼转速2300 r/min不变,对比研究了11种喷头、4种代表性助剂以及不同温度/相对湿度条件对雾滴飘移的影响,采用飘移潜在指数(DIX)及相对减飘率(DPRP)两项指标进行对比评估。结果表明:在温度/相对湿度为20℃/RH 80%条件下,不同类型喷头喷雾药液在空中垂直面和水平距离上的飘移沉积量分布均呈现显著的规律性变化趋势,与对照喷头F110-03相比,喷头飘移潜在性从大到小依次为:TR80-0067>ST110-0067>XR110-01>ST110-015>TR80-01>ST110-02>XR110-03>对照F110-03>IDK系列,其中IDK120-01与IDK120-015喷头的减飘移效果相近并为最好;在30℃/RH 40%条件下,采用XR110-01喷头,分别添加助剂0.5%Silwet DRS-60、1.0%"迈飞"(MF)和1.0%Y-20079后,与不添加助剂的对照相比,平均减飘率分别为43.3%、15.6%和5.2%,表明不同助剂对飘移的影响不同,需考虑助剂类型及其减飘效果合理选用;在20℃/RH 40%、20℃/RH 80%、30℃/RH 40%和30℃/RH 60%条件下,XR110-01喷头与添加1.0%MF助剂组合有利于空中飘移的减少,尤其是高温/低湿条件下,添加助剂的减飘移效果较好。该研究结果可为植保无人飞机的喷头选择、喷雾助剂筛选和实际应用提供参考和指导,并为进一步研究喷头及助剂的减飘技术提供数据基础。 相似文献
9.
BACKGROUND: The objective of this study was to investigate spray drift from a conventional field sprayer as influenced by meteorological and technical factors, and to provide spray operators with data on which to base sound judgements when applying pesticides. The study was conducted in grazing fields and cereal crops. RESULTS: Interpreting the results from 15 field trials under varying meteorological conditions using different boom heights and driving speeds indicates that, during normal spraying conditions, the most decisive factors influencing the total spray drift (TSD) will be boom height and wind speed, followed by air temperature, driving speed and vapour pressure deficit. One important finding was that TSD (within the encompassed range of meteorological conditions and a boom height of 0.4 m) could be expressed as a simple function of the fraction of droplets ≤ 100 µm. In cereal crops: TSD = 0.36 + 0.11× [fr. (d ≤ 100 µm)] and in grazing fields, TSD = 1.02 + 0.10× [fr. (d ≤ 100 µm)]. In most cases a fraction of the airborne drift passed over the 6 m sampling mast located 5 m downwind of the spray swath. CONCLUSIONS: Under specified conditions, the present results indicate a simple relation between the total spray drift and volume fractions of droplets ≤ 100 µm. Given the nozzle type, it was concluded that the most decisive factors determining TSD are wind speed and boom height. Evaluating the relative importance of the meteorological and technical factors contributes to increasing knowledge in this field of research. Copyright © 2011 Society of Chemical Industry 相似文献
10.
BACKGROUND: In this study, the collecting efficiency of different samplers of airborne drift was compared both in wind tunnel and in field experiments. The aim was to select an appropriate sampler for collecting airborne spray drift under field conditions. RESULTS: The wind tunnel study examined three static samplers and one dynamic sampler. The dynamic sampler had the highest overall collecting efficiency. Among the static samplers, the pipe cleaner collector had the highest efficiency. These two samplers were selected for evaluation in the subsequent field study. Results from 29 individual field experiments showed that the pipe cleaner collector on average had a 10% lower collecting efficiency than the dynamic sampler. However, the deposits on the pipe cleaners generally were highest at the 0.5 m level, and for the dynamic sampler at the 1 m level. CONCLUSIONS: It was concluded from the wind tunnel part of the study that the amount of drift collected on the static collectors had a more strongly positive correlation with increasing wind speed compared with the dynamic sampler. In the field study, the difference in efficiency between the two types of collector was fairly small. As the difference in collecting efficiency between the different types of sampler was small, the dynamic sampler was selected for further measurements of airborne drift under field conditions owing to its more well‐defined collecting area. This study of collecting efficiency of airborne spray drift of static and dynamic samplers under field conditions contributes to increasing knowledge in this field of research. Copyright © 2011 Society of Chemical Industry 相似文献
11.
多旋翼植保无人机喷施新烟碱类杀虫剂对蜜蜂的飘移风险 总被引：2，自引：0，他引：2
为明确植保无人机喷施新烟碱类杀虫剂对非靶标生物蜜蜂的飘移风险,在田间试验场景下,比较分析多旋翼植保无人机和背负式电动喷雾器喷施新烟碱类杀虫剂时的雾滴飘移量及对蜜蜂的影响。结果表明：应用背负式电动喷雾器和多旋翼植保无人机进行施药作业时,距离施药区下风向5 m处的雾滴飘移率分别为0.50%和23.98%;而多旋翼植保无人机施药时,即使距离施药区下风向17 m处的雾滴飘移率仍高达2.79%,且多旋翼植保无人机施药时的飘移总量显著高于背负式电动喷雾器。喷施新烟碱类杀虫剂时,应用背负式电动喷雾器作业时距离下风向5 m处的蜜蜂在施药后1 d内的死亡数量为75头,分别是距离下风向17 m处和对照组的2.4倍和1.8倍,施药后2~8 d内蜜蜂的死亡数量与对照组无明显差异;应用多旋翼植保无人机作业时距离下风向5 m处的蜜蜂在施药后1 d内的死亡数量为4 721头,分别是距离下风向17 m、29 m处和对照组的3.0倍、6.1倍和112.4倍,施药后2~8 d内蜜蜂的死亡数量明显降低,但距离施药区较近的蜜蜂其死亡数量明显高于对照组,表明多旋翼植保无人机喷施新烟碱类杀虫剂对蜜蜂存在较高的飘移风险。 相似文献
12.
J. J. SPILLMAN 《EPPO Bulletin》1983,13(3):425-431
There are many diverse views about the effects of wind on aircraft sprays. Some operators wish to spray only when the air is still, others will not spray unless the wind speed is at least 3 m/s. The basis of this difference is the fear of, as against the use of, the downwind movement of droplets. This note uses a simple model of droplet behaviour in a wind to try to predict the deposit distributions downwind of a spraying aircraft. The results demonstrate that the level of turbulence caused by the wind blowing over the earth's vegetation reduces the downwind distance most small drops travel before being captured. Trees create more turbulence than cereal crops, which create more turbulence than bare earth or short grass. The deposit density at a given distance downwind reduces with decrease in aircraft flying height, wind speed and smoothness of the canopy. It remains roughly constant with increasing droplet size until a critical diameter is reached when it falls rapidly with increase in droplet size. This critical size depends upon windspeed and turbulence intensity. A downwind buffer zone between the spray area and a sensitive crop is desirable and its minimum size can be determined using the techniques discussed in the paper. 相似文献
13.
农业航空喷雾雾滴漂移及其数学分析 总被引：1，自引：0，他引：1
通过田间试验研究,探索了装配GP—81喷头的运五型飞机喷洒2,4—D丁酯乳油稀释液的雾滴漂移状况,建立了有关数学模型。研究表明,较低蒸发度的水雾滴漂移距离为340m,较高挥发度的2,4—D丁酯漂移距离达700m;雾滴密度和沉降量随下风距离增加而减小较快,雾滴直径减小较慢;气象因子和喷液配方对雾滴漂移有重要影响;三次多项式方程Y=b_0 b_1X b_2X~2 b_3X~3能很好地描述雾滴漂移与下风距离的关系,模型中的参数具有明确的实际意义,提出了喷洒2,4—D丁酯时的有效隔离带宽度。 相似文献
14.
航空喷雾植保技术的发展与探讨 总被引：3，自引：0，他引：3
航空喷雾在我国农作物病、虫、草害防治中得到了广泛应用。为促进航空喷雾技术的发展,本文对国内外航空喷雾的发展历程、作业技术以及作业设备进行了简要概述和总结,并结合我国航空植保技术的现状,在航空喷雾作业机型、应用技术以及作业装置等方面进行了探讨。通过综述分析,作者认为在我国航空喷雾技术领域,应重视和逐步发展直升机、无人机的应用,加强作业设备控制系统的研发和喷洒部件的系列化与配套,深入进行航空喷雾飘移控制技术研究,以提高我国航空植保应用水平。 相似文献
15.
United States Department of Agriculture-Agricultural Research Service research in application technology for pest management 总被引：1，自引：0，他引：1
A research summary is presented that emphasizes ARS achievements in application technology over the past 2-3 years. Research focused on the improvement of agricultural pesticide application is important from the standpoint of crop protection as well as environmental safety. Application technology research is being actively pursued within the ARS, with a primary focus on application system development, drift management, efficacy enhancement and remote sensing. Research on application systems has included sensor-controlled hooded sprayers, new approaches to direct chemical injection, and aerial electrostatic sprayers. For aerial application, great improvements in on-board flow controllers permit accurate field application of chemicals. Aircraft parameters such as boom position and spray release height are being altered to determine their effect on drift. Other drift management research has focused on testing of low-drift nozzles, evaluation of pulsed spray technologies and evaluation of drift control adjuvants. Research on the use of air curtain sprayers in orchards, air-assist sprayers for row crops and vegetables, and air deflectors on aircraft has documented improvements in application efficacy. Research has shown that the fate of applied chemicals is influenced by soil properties, and this has implications for herbicide efficacy and dissipation in the environment. Remote sensing systems are being used to target areas in the field where pests are present so that spray can be directed to only those areas. Soil and crop conditions influence propensity for weeds and insects to proliferate in any given field area. Research has indicated distinct field patterns favorable for weed growth and insect concentration, which can provide further assistance for targeted spraying. 相似文献
16.
Christopher M. Riley Charles J. Wiesner William R. Ernst 《Pest management science》1989,26(2):159-166
Off-target drift and deposition of aerially applied deltamethrin sprays in an agricultural situation were determined using stainless steel (20 × 40 cm) ground deposit samplers and ‘Rotorods’. Off-target spray deposition decreased exponentially with distance in situations where applications were made in winds with speeds equal to, or just above, maximum label limits for aerial application (8 km h?1). The results are compared with those of previous studies. The effectiveness of a 100-m ‘no spray’ buffer zone in reducing off-target deposit is evaluated. 相似文献
17.
单一行带式乔木固沙林内风速流场和防风效果风洞实验 总被引：3，自引：1，他引：2
文中研究在风速为10m/s和15m/s的风洞实验条件下,覆盖度为20%和25%的两种单行一带模式固沙林内的水平和垂直空间的风速变化情况,达到对两种不同模式的风速流场和防风效果进行比较分析的目的。通过分析可以得出,两种配置模式都形成了风影区和风速加速区相互组合的复杂的水平流场结构。两种模式对垂直空间风速影响相近,根据对不同高度风速的不同影响划分为地表加强层(0.8 cm以下)、微变化层(1.2 cm)、显著变化层(1.6 cm和3 cm)和稳定变化层(6 cm-35 cm)这四个变化层。从距地表1.6 cm高度开始,垂直空间风速变化沿来风方向的风速总体上是逐步减小的趋势,且在林带处会出现一个峰值。总的来讲两种模式降低水平空间和垂直空间风速的效果都相同,但沿林带方向降低水平空间风速的效果有所不同,两种模式降低垂直风速的效果从地表向上都表现出先增加后减少的趋势。 相似文献
18.
为研究多旋翼植保无人飞机施药时农药雾滴飘移规律以及施药作业人员职业暴露情况，依据喷雾飘移田间测试国际标准ISO22866和人体暴露贴片测试法，对多旋翼植保无人飞机和电动背负式喷雾器在水稻田喷施氯虫苯甲酰胺和苯醚甲环唑时的农药雾滴飘移量及施药作业人员人体农药沉积量进行了对比测试和分析评价。结果表明:在本试验环境条件下，多旋翼植保无人飞机在作业速率4 m/s和作业高度1.8 m参数下施药时，在距施药区下风向边界0~30 m范围内地面均有农药飘移性沉积，30 m处氯虫苯甲酰胺飘移率为0.9%，而背负式喷雾器施药的飘移量则主要集中在距施药区0~3 m区域内，3 m以外区域飘移率均≤0.6%；背负式喷雾器在距施药区5 m以及10 m远处空中不同高度的飘移量均小于0.001 μg/cm2，多旋翼植保无人飞机在距施药区5 m远处空中的飘移量大于10 m处，并且在垂直分布上，距冠层2 m左右 (无人飞机的飞行高度) 处飘移量最多。结合两种施药机具的雾滴粒径(背负式喷雾器DV50 值为149.4 μm，多旋翼植保无人飞机DV50 值为115.3 μm) 分析，无人飞机的雾滴具有更高的飘移潜力。由于实现了人机分离，多旋翼植保无人飞机进行作业时人体暴露量很低，而背负式喷雾器施药时对作业人员身体各部位均会造成一定的暴露，其中以手前臂和腿部正面暴露最为严重，在施用苯醚甲环唑时，右前臂背面暴露量最高，达到15.19 μg/cm2。本文中针对多旋翼植保无人飞机喷雾作业时在下风向的飘移沉积研究方法和试验结果，以及对多旋翼植保无人飞机施药过程中职业暴露的研究，可为农药喷雾作业缓冲区距离确定和人员作业安全评估提供参考。 相似文献
19.
巴丹吉林沙漠拐子湖地区贴地层风速廓线和风沙流结构特征 总被引：1，自引：0，他引：1
野外监测试验表明：自由风和风沙流廓线拟合虽都以Z=A·exp(-X/T)+Z1形式分布,但在风沙流中拟合系数更高;风沙流结构中,在20 cm以下随着高度的增加,各高度的输沙率百分比、含沙浓度、运动颗粒能量都呈增大趋势;20 cm以上随高度增加,各高度输沙率百分比变小,输沙率占总输沙率的51%左右,含沙量主要集中在离地面20 cm以内;风沙流在垂直方向上,高度与含沙平均粒径呈负相关,风速与含沙平均粒径变化呈正相关。这些结论对拐子湖地区防风治沙有重要的指导意义。 相似文献
20.
Frampton GK 《Pest management science》2002,58(10):991-1001
During a 6-year study, effects of two contrasting regimes of pesticide use on pitfall and suction catches of Collembola were monitored in an arable field under a rotation of grass and winter wheat. Current farm practice (CFP) represented conventional fungicide and herbicide use plus applications of organophosphorus (OP) insecticides, whereas reduced input approach (RIA) utilised minimum inputs of fungicides and herbicides and excluded any use of insecticides. Compared with RIA, the CFP regime caused a substantial decline in the abundance and diversity of Collembola in the field, including the local disappearance of one species, without recovery during the study. At the field edge, which was protected during OP applications by a 6-m unsprayed buffer zone, effects of the CFP regime were less severe, and were not persistent in the long term. Some Collembola species occurred only in field-edge samples. Pitfall and suction sampling yielded remarkably similar patterns of catches, indicating that pitfall trapping may be appropriate for detecting long-term changes in collembolan abundance caused by intensive agricultural management practices. 相似文献