Through water savings and a decrease in yield variability, variable rate irrigation (VRI) technology may be an effective tool to optimize irrigation in potato crops. However, the potential economic and agronomic benefits of this technology are still unclear, especially over varying agricultural landscapes. We hypothesize that VRI technology will be a valuable tool when used on potato fields that have a high degree of soil and topographic heterogeneity. This hypothesis is tested using field-level data from 2019, 2020 and 2021 collected in the Lethbridge region.
We define a site-specific crop-water production function based on the water balance and physical properties of unique management zones within a field, which includes the impact of the soil and topographic complexity of each management zone. The function is used in an economic optimization model to determine the benefits of VRI technology relative to uniform irrigation. We simulate a per-unit water price and a drought-induced water constraint to examine the performance of VRI technology under unique environmental and policy conditions. Our study is one of the first to apply experimental field data in an economic optimization model to estimate the benefits of VRI relative to uniform irrigation.
