Direct and indirect drift assessment means. Part 4: a comparative study.

Area of Science:

• Agricultural Engineering
• Environmental Science
• Pesticide Application Technology

Background:

• Pesticide drift poses environmental risks, necessitating accurate assessment methods.
• Evaluating spray drift is crucial for minimizing off-target pesticide deposition and ensuring application efficacy.

Purpose of the Study:

• To compare the effectiveness of three drift risk assessment methods: PDPA laser measurements, wind tunnel experiments, and field drift experiments.
• To evaluate the potential of indirect drift assessment means (PDPA, wind tunnel) against direct field measurements.
• To establish relationships between droplet characteristics and pesticide drift potential.

Main Methods:

• Conducted 90 PDPA laser measurements, 45 wind tunnel experiments, and 61 field drift experiments.
• Investigated 10 different spray nozzles (ISO 02-06) and types (standard, low-drift, air inclusion) at 3.0 bar pressure.
• Utilized first-order linear regressions relating droplet size and velocity to predict drift.

Main Results:

• Indirect methods (wind tunnel, PDPA laser) provide comparable and repeatable conditions for driftability experiments.
• Both indirect methods are suitable for relative studies of pesticide drift risk.
• A statistical drift prediction equation based on indirect measurements can realistically estimate field drift data.

Conclusions:

• Indirect drift risk assessment methods are valuable tools for evaluating pesticide drift.
• Wind tunnel and PDPA laser measurements can be used to predict field drift losses under specific conditions.
• These methods facilitate comparative studies and realistic estimations of spray drift, aiding in risk management.