Agricultural Water Use and Management Challenges on the Canadian Prairies

GWFO User Advisory Panel member, Doug Heath, Research Manager at Sask Oilseeds, introduced Professor Ireson who opened by noting the global challenge of agricultural water use and highlighted the need for increased food production by 2050. The agriculture sector accounts for 72% of freshwater withdrawals globally. On the Prairies, increasing food production with limited land and water requires making the most of available moisture. Seasonal snow and snowmelt are important to the region’s water supply, while transpiration represents the productive use of water that directly supports crop growth. Runoff and deep percolation, by contrast, can represent water lost from the crop system. As climate change alters temperatures, particularly in winter, understanding and adapting to these changing water dynamics will become increasingly important for Prairie agriculture. This is why scientific observatories that collect data about soil moisture and groundwater are key players in informing research that leads to more effective government policy and producer practice. 

Climate change can affect both how much precipitation the Prairies receive and how quickly water is lost through evaporation and plant use. Because producers cannot control precipitation, management practices must focus on keeping more of the water that does arrive available to crops. 

Professor Ireson highlighted how producers can make better use of limited Prairie water supplies by capturing and retaining moisture before and during the growing season. Long-term observations from instrumented sites across Saskatchewan show that snow redistribution and snowmelt pathways can have an important influence on the water available to crops. Practices such as maintaining standing stubble can help retain snow and potentially increase crop-available water by about 20%, while no-till practices can promote infiltration during snowmelt. With roughly one-third of crop water use coming from pre-growing season sources such as snowmelt and fall rainfall, these strategies could become increasingly important as climate change affects precipitation and evaporative demand. 

Soil Moisture and Crop Yield Modeling Findings