An-Gel Pilot Trial – High-Precision Spraying – CIM Viseu Dão Lafões

Summary

This is a pilot project under the An-Gel programme that evaluates a high-precision microsprinkler system to protect vineyards against spring frosts in Viseu (Portugal). The solution consists of spraying water to maintain plant temperature and prevent damage, offering an efficient, sustainable, and low-energy alternative to reduce agricultural losses.

Description

Context

The Viseu Dão Lafões region presents climatic conditions that are particularly sensitive to cold air accumulation due to its landscape. This leads to spring frost episodes that severely affect strategic crops such as vineyards (Dão) and apples (Bravo de Esmolfe).

These frosts coincide with critical phases of the vegetative cycle:

Vine: damage to buds and young shoots, potentially causing losses of up to 100% of production.
Apple tree: impact during flowering and fruit set, reducing fruit quality and commercial value.

Pilot solution

The pilot experience is carried out in a 15-year-old vineyard of the Touriga Nacional variety, located at the Escola Superior Agrária de Viseu (Portugal), in the Viseu Dão Lafões region.

Within the framework of the An-Gel project, a high-precision spraying system using microsprinklers has been implemented as an active adaptation and mitigation measure against frost. This system continuously sprays water during cold episodes; as it freezes on the plant, latent heat is released, keeping the tissues at 0 ºC and forming a layer of ice that acts as thermal insulation, preventing damage.

Advantages:

High effectiveness in crop protection
Lower energy consumption compared to other methods
Reduced labour requirements
Low environmental impact

Actions and impact

Various actions have been carried out in the pilot plot, including the installation of the water distribution system (pipes and fittings), the implementation of microsprinklers in the vineyard, the commissioning of the pumping and automation system, as well as necessary construction works such as trench excavation and infrastructure assembly.

This experience will allow the effectiveness of the system to be evaluated under real field conditions, contributing to the reduction of economic losses caused by frost. Furthermore, it will facilitate the generation of transferable knowledge to other regions of the Sudoe area and promote the development of sustainable solutions for climate change adaptation.