In the heart of China, researchers are taking to the skies to revolutionize how we understand and manage water use in agriculture. Led by Na Liu from the Key Laboratory of Agricultural Water Resources in Shijiazhuang, a team of scientists has developed a novel method using unmanned aerial vehicles (UAVs) to assess water productivity in winter wheat cultivars. This breakthrough, published in the journal Agricultural Water Management (which translates to Agricultural Water Management), could significantly impact the energy sector by optimizing water use and enhancing crop yields.
The study focuses on crop water productivity (WP), a crucial metric that measures grain yield or biomass production per unit of water consumed. With water scarcity becoming an increasingly pressing issue, identifying and cultivating wheat varieties with high WP is essential for sustainable agriculture. Traditional methods for measuring WP are labor-intensive and time-consuming, but Liu and her team have found a more efficient way.
“Our goal was to develop a non-destructive, high-throughput method for phenotyping cultivars with high water productivity,” Liu explains. The team turned to UAVs, which can capture high-resolution remote sensing data, providing a detailed view of crop health and water use over time.
The researchers assessed the WP of 10 winter wheat cultivars under three different irrigation levels. They used a combination of the SEBAL (Surface Energy Balance Algorithm for Land) model, crop coefficient, and soil water balance equation to estimate daily evapotranspiration (ET)—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. This data, along with biomass estimates derived from multispectral UAV imagery, allowed the team to calculate WP for different growing periods.
One of the study’s key findings is that the WP at the biomass level around the flowering stage is significantly correlated with the WP at the grain yield level. This means that monitoring WP during this critical period can provide a reliable indicator of a cultivar’s final water productivity. “The biomass accumulation during this stage is crucial for final grain production, and the daily ET also peaks at this time,” Liu notes.
The implications of this research are far-reaching. By enabling rapid, non-destructive assessment of WP, UAVs can help farmers and agronomists make more informed decisions about water management and cultivar selection. This could lead to significant water savings and increased crop yields, benefiting both the agricultural and energy sectors.
As water becomes an increasingly precious resource, the ability to optimize its use in agriculture will be vital. This study demonstrates the potential of UAVs and remote sensing technologies to drive innovation in the field. As Liu and her team continue their work, the future of water management in agriculture looks increasingly bright—and efficient.