In the heart of California, where avocado orchards stretch across the southern and central coasts, a silent battle for water is underway. As the state grapples with uncertain water supplies and mandatory reductions, farmers are seeking innovative ways to optimize irrigation and conserve this precious resource. A groundbreaking study, led by Aliasghar Montazar from the University of California Division of Agriculture and Natural Resources, UCCE Imperial County, is shedding new light on how to achieve just that.
Montazar and his team have been meticulously collecting data from five avocado sites across major production regions over three years. Their mission? To quantify evapotranspiration—the process by which water is transferred from the land to the atmosphere by evaporation from the soil and other surfaces and by transpiration from plants—and to develop precise crop coefficient values for ‘Hass’ avocados. These coefficients are crucial for determining the water needs of crops and optimizing irrigation strategies.
The study, which utilized cutting-edge ground- and remote-sensing technologies, has revealed that water consumption in avocado orchards is significantly influenced by site-specific conditions. “We found considerable variability in crop coefficient values both spatially and temporally,” Montazar explains. “This means that a one-size-fits-all approach to irrigation just doesn’t work.”
The researchers measured actual crop evapotranspiration (ETc act) using a combination of eddy covariance and surface renewal techniques. They discovered that seasonal ETc act totals ranged from 713 mm to 1028 mm across the experimental sites and study seasons. Moreover, they found that water consumption varied greatly depending on the growth phase of the avocado trees. “We saw greater crop coefficient values during the flower bud development and flowering through fruit set growth phases,” Montazar notes. “This is a critical finding for farmers, as it allows them to tailor their irrigation strategies to the specific needs of their crops at different stages of growth.”
The implications of this research for the energy sector are significant. Efficient water use is not just about conservation; it’s also about energy savings. Pumping, treating, and transporting water requires substantial energy inputs. By optimizing irrigation, farmers can reduce their energy consumption and lower their operational costs. Furthermore, as water becomes scarcer and more expensive, the ability to accurately determine crop water needs will become increasingly valuable.
The study also provides valuable insights for local water districts. By understanding the water needs of avocado orchards, these districts can better manage their water delivery and conservation programs. This is particularly important in regions like California, where water supplies are uncertain and the cost of water is rising.
The research, published in the journal ‘Agricultural Water Management’ (translated to English as ‘Agricultural Water Management’), is a significant step forward in the quest for resource-efficient and profitable avocado production. It provides farmers with a more reliable, usable, and affordable way to determine the water needs of their orchards. And as the demand for avocados continues to grow, so too will the need for innovative solutions like these.
As Montazar puts it, “This research is about more than just avocados. It’s about finding sustainable solutions for agriculture in a changing climate. It’s about ensuring that we can continue to produce the food we need, while also conserving our precious water resources.” The future of avocado farming in California—and indeed, the future of agriculture—may well depend on it.
