Farm Table says:
What is the problem?
Efficient use of irrigation is essential to meet food production needs of growing global populations while ensuring long-term sustainability of freshwater resources.
However, lack of on-farm irrigation data constrains understanding of irrigation variation and no framework exists to benchmark irrigation use using actual irrigation data.
What did the research involve?
The thesis investigates variation in irrigation using a database of 1400 maize and soybean fields over 9 years in Nebraska and presents a framework to benchmark irrigation use using a separate database of ca. 1000 maize and soybean fields in Nebraska as proof of concept.
“State-of-the-art” crop models estimated yield potential and irrigation water requirements for each field-year observation and were compared against producer-reported yield and irrigation
What were the key findings?
Findings illustrate the difficulty of predicting field-scale irrigation due to multiple biophysical and behavioral factors driving irrigation decisions.
Producers respond to their field conditions and attempt to make irrigation decisions accordingly. However, use of a robust and transferrable framework to benchmark irrigation water use revealed that many fields received surplus irrigation in Nebraska. Potential exists to reduce surplus irrigation usage without decreasing maize and soybean yield
The framework developed can be used to benchmark irrigation use for crop production at different spatial levels (field, region, state), help prioritize extension and research activities, and inform policy and incentive programs.