Water-Smart Agriculture: the Efficiency Drive the World Needs
This is a version of an article which appeared in November 2019’s Irrigazette, a leading international irrigation magazine.
We are in the midst of an unprecedented water crisis. South American regions are declaring an agricultural state of emergency, California’s wells are running dry, and countries from Belgium to Botswana are facing significant water stress. In a “business-as-usual” scenario these problems are only set to multiply: “Water scarcity is projected to increase with the rise of global temperatures as a result of climate change,” states Sustainable Development Goal 6.
This is not just an agricultural problem – water scarcity has far-reaching effects as people are forced to flee drought- or salinity-ridden areas; a 2018 World Bank report estimated that by 2050 there may be up to 143 million “climate refugees”.
Hence water management in irrigated agriculture can have distant and often overlooked humanitarian, economic and societal impacts. And with agriculture accounting for over 70% of the world’s fresh water use, innovation has to start here.
But if the history of agriculture tells us anything, it’s that it consistently brings out the best human innovative spirit.
And this is exactly what’s happening around the world, with huge efficiency drives through Climate-Smart Agriculture (CSA).
CSA is all about the interdependencies between yields, and impacts and outcomes related to carbon, soil, water use and biodiversity. Spearheaded by the Food and Agriculture Organization of the United Nations, it is “an approach that helps to guide actions needed to transform and reorient agricultural systems to effectively support development and ensure food security in a changing climate”. It has three simultaneous goals and interlinking objectives: increased productivity and incomes, adapting and building enhanced resilience, and reducing emissions associated with agriculture.
As an irrigation community, we need to take this further and define a new Water-Smart Agriculture (WSA), dealing with each of these goals through improved water efficiency.
Let’s look at how each of the CSA objectives relate directly to smart water management and to a new era of Water-Smart Agriculture.
Objective 1: Increased productivity
Doing more with less has become the mantra of a new sustainability drive in agriculture, and this goes as much for water use as anything else. New innovations are making it increasingly possible to do just this – increased yields (output) while using less resources (input), in ways which would have seemed mathematically impossible just a generation ago.
Agriculture 4.0 is moving growing far beyond old-school trial and error, manual measurements, and assumptions, and instead towards ultra-efficiency, sensors, and big data. “Without measuring, we do not actually know how the plant truly reacts towards all external conditions – this is what we want to change with real-time feedback,” says Olivier Begerem at Belgian start-up 2Grow. For water efficiency, this means maximizing existing water use by monitoring a plant’s vegetative/generative stages to see the exact effect of inputs. As well as sensors, Ag 4.0 also involves use of drones, satellite imagery, and big data, to monitor the exact impact of irrigation cycles.
According to consulting firm Oliver Wyman, “Agriculture 4.0 will no longer depend on applying water uniformly across entire fields. Instead, farmers will use the minimum quantities required and target very specific areas” – through precision irrigation.
Increased precision is imperative for improving overall Water Use Efficiency (WUE), “the ratio between effective water use and actual withdrawal”. This is most often associated with drip irrigation, but also encompasses variable rate application, flow rate monitoring, and precision treatment solutions which alter water at a structural level . Eric Valette, CEO of Aqua4D and expert in the field of water treatment says: “Increasing the Water Use Efficiency of irrigation systems through precision irrigation is absolutely key to dealing with water stress and becoming a water-smart grower. New treatment technologies make it possible to get the most out of every drop, maximizing the potential of irrigation systems while ensuring increased yields and optimized production.”
Aqua4D study underway at a Swiss greenhouse, mid-2019
But optimizing water inputs is just one half of the solution – just as imperative is ensuring this moisture stays in the soil long enough for plants to take advantage of it. Growers with irrigation solutions which optimize both the water itself and its behaviour in the soil will have an added competitive advantage going forward.
Simply put, if soils can stay moist for longer, irrigation times and frequency can be significantly reduced. There is plenty of research under way looking at maintaining this soil moisture where it’s most needed. This includes everything from using peat moss, perlite (a volcanic glass), membranes and more, to increase absorption properties. Ag 4.0 innovations such as Spiio or Sentek’s sensors keep track of soil moisture in real-time, which can save water through maintaining optimum conditions. But focusing on the actual water rather than the soil can have a range of impacts: technologies such as Aqua4D target the irrigation water itself, subtly changing its structure so that it penetrates the soil pores, thus staying moist for longer periods.