9 minute read
The water footprint of food
A triple win? Agrivoltiacs - the use of land for both crops and solar power generation – has been shown to significantly reduce water use and increase yields.
As the UN puts it, “efficiency measures along the entire agrifood chain can help save water and energy, such as precision irrigation based on information supplied by water providers, and protection of ecosystems alongside agriculture and energy production.”
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Technologies that save water have knock-on positive benefits for agriculture and energy.
“Building climate resilience is also building water resilience and it has to be understood as such,” says Olson-Sawyer. “If you really want to tackle climate change you have to address the problems with water-related risks. Just look at Pakistan, this year they had an incredible drought and then suddenly one third of the country was inundated. Agriculture will have to adapt with this reality. Water security is food security.”
Subirrigation using treated wastewater
We spoke to Ruud Bartholomeus, Chief Science Officer & Principal Scientist Ecohydrology at KWR Water Institute, about how subirrigating crops with treated wastewater can reduce agriculture’s water footprint.
What are some of the water-related challenges facing the agricultural sector?
Agricultural crop yields depend largely on soil moisture conditions in the root zone. Climate change leads to more prolonged drought periods that alternate with more intensive rainfall events. With unaltered water management practices, reduced crop yield due to drought stress will increase.
Both farmers and water management authorities must search for opportunities to manage risks of decreasing crop yields. The good news is that strategies are being developed to control these risks and to secure long-term supplies of freshwater. These include increasing regional self-sufficiency in meeting the demand for freshwater and improving the utilisation of the available water sources.
How do you think the water industry can help agriculture overcome some of these challenges?
Available groundwater sources for irrigation purposes are increasingly under pressure due to regional coexistence of land use functions that depend on groundwater levels or compete for available water. At the same time, treated wastewater from industries and domestic wastewater treatment plants is quickly discharged via surface water towards the sea. Exploitation of these freshwater sources may be an effective strategy to balance regional water supply and agricultural water demand.
Treated wastewater (both from domestic and industrial origin), that is usually discharged from a catchment, can be used for local-scale water supply by subirrigation. The goal of subirrigation is to raise the groundwater level and improve the soil moisture conditions for plant growth through capillary rise. The use of these treated wastewater for subirrigation purposes may be an effective strategy to contribute to both improved water availability for crops and a reduced pressure on the regional groundwater system.
What water technologies and innovations will be important?
Besides the technology of subirrigation itself, the quality of the water source used for subirrigation is key. In order to use treated wastewater for irrigation in agriculture, further purification of wastewater will be needed.
The development of sewage treatment plants towards so called ‘water factories’ will contribute to the responsible reuse of treated wastewater in agriculture.
How does you organisation help agriculture build resilience?
Water availability for subirrigation, for instance, is generally not limited and could lead to negative impacts to other users of the water system, if not implemented well. We provide analyses of the propagation of (climate) adaptation measures through the hydrological system including a clear visualisation to support water managers. We guide water managers to a responsible implementation of the measures, integrating aspects of water quality, water quantity, water treatment and governance. Additionally, we execute pilot studies to quantify the risks and benefits of adaption measures like water reuse.
The role of watertech
If you ask any grower, they will tell you that water is paramount for realising their yield. Water has always been the protagonist for growers.
Unfortunately, however, water has become the antagonist, the story’s disrupter, destroying lives and livelihoods, especially in the Global South. Yet, thanks to recent innovations in hardware, software, and business models, growers of all crops and all geographies can now manage water-related risks in ways their predecessors could only dream of.
In areas where crops are primarily rain-fed, rainwater can be used much more efficiently through relatively low tech capture, storage and reuse technologies. In areas where irrigation is needed (40% of global food production), efficient technologies such as drip irrigation can reduce water consumption by 30-70% and improve yields by 30-200%.
There are also technologies readily available today that address flood risks, enable farmers to extract water from alternative sources and help farmers make better decisions and predict future scenarios though data. There are a host of digital technologies that help growers gather more accurate data from the environment and display this data in meaningful ways.
Water innovations for agriculture
One can typically segment watertech for agriculture into three parts:
1. Innovations that help growers to gather more accurate data from the environment, processes, equipment and infrastructure and from the water itself, whether quantity (too much/too little), or quality (not suitable for intended use).
These include: In-situ sensing, IoT, Earth observation (eg: satellite), Connectivity, Analog to digital conversion. The sensing toolbox of innovations that observe, quantify and digitize anything related to water quality and quantity and sends the data to the cloud.
2. Innovations that help growers with data management (scrubbing and normalisation) and to help correlate the datasets and draw inferences. Innovations include: Artificial Intelligence, Machine Learning, Deep Learning, Neural Networks, Bioinformatics, and Modelling/digital twins. Essentially, the data science toolbox of innovations that convert water-related data from disparate sources
3. Innovations that help growers address the challenges of our new climate-change-induced “water reality" in the most effective and cost-efficient way. Innovations include tech that addresses water quality such as purification including membranes, filter media, electrochemistry, biomimicry, etc. This also includes tech that addresses water quantity, such as:
1) Flood protection: earthworks, green infrastructure, etc.
2) New water sources: atmospheric water generation, desalination, reuse, etc. and
3) Efficiency and stewardship including smart monitoring and irrigation tools.
In November, leaders across government, industry, and civil society met at the The Global Food Security Forum in Bali to assess food security as a global challenge and offer bold solutions for strengthening food systems, securing supply chains, and fighting world hunger. One of the panel speakers was Erez Fait, co-founder and president at Agrinoze, who was there to discuss how the company’s fully automated, real-time system for precision irrigation can help address the global food crisis.
Globally, almost one in ten people don’t have enough food to eat, and 3.1 billion people can’t afford a healthy, nutritious diet. Food prices have risen by about 20% year-on-year over the last decade and fertiliser prices have soared by as much as 300% in some regions. Increasingly severe droughts and water scarcity, exacerbated by climate change, are adding fuel to the fire.
The World Resource Institute estimates that we will have to produce 50% more food by 2050, without using any more land. Reaching this target and achieving global food security will require fundamental, sweeping reforms in the way we produce food and manage the natural environment.
This was the grand challenge guiding the conversation at The Global Food Security Forum. And Erez Fait believes he has a solution.
Fait says that the global agri-food system has been relying on ‘outdated growing methods’ for far too long, methods that waste water, fertiliser and don’t maximise yields per section of land. These techniques are largely based on assumptions about a plant’s needs, not real-time data. This means farmers are often irrigating at the wrong time, in the wrong place and not in tune with a plant’s physiological needs, he says.
To combat this wasteful use of valuable resources, Agrinoze has developed an end-to-end solution for sustainable drip irrigation.
This is how it works. Real-time sensors are deployed in the soil and root zone of crops. These sensors measure and transmit real-time information on water, soil and climatic conditions to a machine learning algorithm that finds the optimal irrigation point for any field. Then the hardware of the operation, an irrigation control room based at the site, controls the distribution of water and fertiliser across the field via non-drain drip line pipes.
This is what Agrinoze calls ‘water on demand’ irrigation - essentially giving plant’s what they need, when they need it. The method has been tested by over 150 farmers globally. Fait says that time and time again, it has consistently resulted in 300% higher yields using 30-60% less water and, in some cases, no fertiliser whatsoever.
In California, Agrinoze deployed its solution across almond and grape fields - some of the most waterintensive crops in the world. Over the test period, the fields using Agrinoze were reported to use 65% less water and no fertiliser, with equal if not better yields.
During the fourth quarter of 2020, Agrinoze tested the impact of its precision irrigation on Cassava, as part of a south-east Asia precision irrigation project.
Cassava is a tropical root crop that provides the staple food of an estimated 800 million people worldwide. Fait says that one of the advantages of the Agrinoze solution is that it can manage aggressive, dense planting protocols like those seen in Cassava plantations.
The cassava seedlings were planted with a spacing of 50 cm x 50 cm, twice as dense as traditional spacing. 3 months after planting, several cassava roots were harvested for testing. The roots were measured and tested by a local lab and were found to be suitable for marketing after a third of the typical cycle. Not only were the plants ready much faster, the yields were increased by almost 300% compared to usual methods, with approximately 50% of water and 50% of fertilisers saved.
Whether it’s melons in California, bananas in Israel or corn in South-East Asia, Agrinoze seems to have proven that precision irrigation based upon real-time data doesn’t just improve yield but saves precious water and fertiliser resources as well.
“Precision irrigation dramatically improves efficiency of crops and saves financial costs while increasing production,” says Fait. “Even though these technologies might seem costly at first glance, farmers make huge savings in the long run. They make more money from increased yields and have lower input costs due to reduced water and fertiliser requirements.”
“Agriculture is undergoing a ‘Digital Revolution’, with immense potential for improving the lives and livelihoods of farmers around the world,” says Riad Meddeb Director at the UNDP Global Centre for Technology, Innovation and Sustainable Development in Singapore.
The UNDP published a report last year Precision Agriculture for Smallholder Farmers detailing the various innovations emerging in the area of digital farming, and how these technologies can support small-scale farming, which produces around one third of the world’s food.
The report recommends that small-scale farmers be supported in digital transformation through funding mechanisms, digital skills training and farmer cooperatives so that solutions like Agrinoze can become scalable across many socio-economic contexts.
Ultimately, digital transformation of agriculture is no longer a nice-to-have but a must have. With support from governments and investors, precision irrigation will no doubt become a staple component of the agri-food system in years to come.
