Sustainable irrigation for the wine industry
A changing climate is having unpredictable consequences on grape crops all around the world. 2017 was anything but a vintage year for wine harvests; the EU hit a 36-year low, while Chilean growers reported an uncharacteristically early harvest with high temperatures and low yields. It’s all set for a rebound in 2018, but with El Niño and La Niña phenomena and the inherent unpredictability of factors outside of their control, growers across the world have been exploring the ways they can manage the factors they can control.
This includes turning to Big Data and IoT (Internet of Things), but also simply a more efficient water management. Consequently, Aqua4D has seen a surge of in interest in its own proprietary irrigation water solutions from around the world, with studies involving grape crops in countries including Ethiopia, Tunisia, Morocco, Argentina, Brazil and Uzbekistan.
Water savings in water-scarce lands
Wine production can be very water-intensive – Arjen Hoekstra at the Water Footprint Network has calculated that it can take between 100 to 200 litres of water to make a 125ml glass of wine. What’s more, production often takes place in semi-arid areas severely prone to drought. For example, California’s wine country experienced a five-year drought up to 2017, while this year Cape Town, capital of the South African wine industry, narrowly averted a “day zero” scenario, with the city’s taps almost dry. In an industry so reliant on water, any potential water savings can prove absolutely crucial.
The Aqua4D system enables this through a more efficient use of irrigation water. The technology subtly changes the physical structure of the water and its interaction with dissolved minerals and biological materials:
How does this result in water savings? Aqua4D proprietary technology improves water retention in the soil, especially in sandy or silty soils. This water also penetrates more easily into the soil pores due to improvement of the capillary effect in the soil, resulting in less loss of water by percolation. Results have shown it is possible to save an average of 25% of irrigation water in this way.
But there’s far more to the sustainability of the system than water savings alone. Excess salt is a problem in agriculture around the world, and soil salinity is a significant concern in most wine-growing regions. Through its action on minerals, the Aqua4D system allows for irrigation with water with a high salt content, without any harm to the plants. This physical treatment of water allows for a better dissolution of minerals and ions; the salts do not crystallize or clog the soil pores:
A plant absorbs minerals not in proportion to their abundance in water but, rather, make a choice between quality/quantity according to its physiological needs. With Aqua4D, plants are no longer ‘penalized’ by an excess of unwanted salts. Salts not consumed by the plant are carried under the rhizosphere. Several studies have shown that when good irrigation practices are applied, salts no longer accumulate in the root zone and that irrigation using the Aqua4D system greatly assists with soil leaching.
This makes for not only healthier soil but healthier plants; as Aqua4D’s South America-based agronomist George Melo explains: “Vines grow better at a salinity level of between 2.0 and at most 2.5 mS / cm, above which there are problems of atrophy and even death of radicles, with nutritional consequences, limiting their production capacity and quality of the fruits.“
Clogging of dripper systems can frustrate irrigation efforts and lead to an unhealthy build-up of algae, biofilm or limescale. Due to the same way the Aqua4D system interacts with the minerals, clogging issues can be solved and prevented without needing to resort to acids or chlorination.
With water savings, solutions for salinity, clogging, and more, let’s take a look at some wineries who have benefitted from the Aqua4D system.
Case study: Castel
The trial at the Castel winery in Ethiopia was conducted on chardonnay crops on two separate plots – one irrigated using the Aqua4D system (6.78 ha) and one irrigated as normal (4.98 ha). Analysis showed that 30% less water was required for the plot irrigated with water treated by the Aqua4D system:
For Castel, however, there were even more startling results. They were irrigating their crops with water with a fairly high sodium content (75mg/L) which had been affecting soil quality and production yields, and had a pH which was slightly above FAO guidelines.
They also saw an end to clogging problems in their localized dripper systems which had been caused by biofilm development. The effect of the Aqua4D system’s low-level EM frequency reduces the adhesion forces between organic matter and pipe surfaces, meaning that biofilm or algae no longer develops as it simply no longer adheres,. In turn, this can significantly increase the longevity of dripper systems and offers notable labour savings – all without the use of any chemicals.
Less conductive soil, more efficient nutrient absorption, and smooth-flowing drippers all had a knock-on effect leading to a 22% jump in yields, moving General Manager Bernard Coulais to comment: “With the Aqua4D system we have observed important water savings, significant production growth, and improved foliar surface area. We recommend the Aqua4D system to growers who want to improve yields while reducing costs – notably through very important water savings.” (original letter in French here)
Case study: Miguel Valencia, Argentina
On the other side of the world is a winery in Mendoza, the wine capital of Argentina, home to the varieties of Criolla Grande, Cereza and, most notably, Malbec. The validation study took place on two plots at Finca Miguel Valencia, an 80 hectares site and an important provider in the region. Despite being half the world away, the site was confronted with issues similar to those at Castel: water with high salt content, as well as soil salinization and clogging. The soil was becoming increasingly salinized, while the drippers were not distributing uniformly, undermining irrigation efforts. A significant presence of carbonates, calcium and sodium was to blame, leading to a high measurement of electroconductivity (EC) – up to 2410 micromhos.
With soil analysis conducted in February and then again in August, the growers were blown away by the almost 4x reduction in soil conductivity , and significantly lower presence of NaCl:
A more specific problem was also present in the soil of the grower, namely that it contained a high clay content which made water percolation difficult. After the installation of the Aqua4D FA-40 system, a significant change was observed in a short time: the soil absorption was hugely improved, making percolation much easier, and showing that the Aqua4D system affects not only on the plant but the soil around it.
Following these successes, another FA-80 system is being installed on an adjacent field, as well as a new system at a nearby winery in Mendoza County.
With these clear benefits to growers in semi-arid regions, further adoption of the system is expected in near future in South America and the Western US. Indeed, in 2018 as the effects of climate change directly hit wine producers in the form of huge fast-spreading wildfires and record-breaking droughts, there is a burgeoning shift to sustainable practices in the wine industry.
A recent Wine Opinions survey in the US showed that consumer demand for sustainably-produced products is increasing and a majority of the $60 billion wine trade consider sustainability when planning for the future. One area north of San Francisco, Sonoma County, aims to become the first 100% sustainable wine region by 2019. “You can’t be in California and farm, and not have water be one of your biggest considerations for sustainability,” says Karissa Kruse, President of Sonoma County Winegrowers. “Especially in California, no one wants to be a water waster.”
In solving salinity issues, improving nutrient absorption, and saving water where it’s most needed, all while increasing yields, Aqua4D hopes to make a big contribution to this sustainability drive in the wine industry.