Tham khảo tài liệu 'herbicides environmental impact studies and management approaches part 7', khoa học tự nhiên, công nghệ sinh học phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Herbicide Reduction Methods 109 exchange between researchers in this field. Systems integrating this technology can become an integral part for the decision support of farmers. Application technology for weed management The application technology for chemical weed management has seen advances in the last decade leading to more precise application of herbicides in the field and thus reducing the amount of herbicides applied. The equipment to apply herbicides to the field plays an important role for an optimized treatment. One concern for an optimum treatment quality is the reduction of drift. In windy weather conditions the drift effect can lead to an uneven treatment because the spray liquid moves from the envisaged position and can stack up in neighbouring areas. The resulting unwanted variation within the field can on the one hand lead to poor weed control due to lower amounts on the other hand damage the crop in vulnerable growth stages and also the environment in areas with higher amounts. It can also lead to pollution of non-target areas outside of the field often in shelter-belts where the wind velocity is reduced. The drift can especially be a problem for targeted omission of sensitive areas near water or biotopes. To comply with restrictions optimal drift reduction is one crucial prerequisite. It can be achieved by selection and calibration of the equipment and naturally by applying under good weather conditions no wind . One way to reduce the drift is the selection of nozzles with larger orifice size producing larger droplets or special drift-reducing nozzles which for example incorporate air into the spray droplets. The droplet size is also dependent on the spray pressure and additives that increase spray viscosity. Bigger droplets are not as susceptible to wind as smaller ones. The selection of the right nozzle is not only dependent on the drift effect but also relying on other circumstances. Smaller droplets can have advantages for the uptake .
