Water Budgets under Contrasting Winter Warming Conditions: A Lysimeter Study in a Humid Continental Climate
Climate change is documented to increase average winter air temperatures, reducing snow-cover in humid continental climate regions. Snow-cover is an insulating layer between the pedosphere and atmosphere which reduces energy and moisture fluxes. Studies are needed to understand how warmer winters impact freeze-thaw cycles (FTC) and water budget inputs, outputs and storage. A warming experiment was conducted using overhead heaters with two soil types in monolithic weighing lysimeters. Two winter warming treatments were applied, a continuous warming to inhibit FTCs, and intermittent warming to increase FTCs. We observed that as soil freezing decreased, the amount of water partitioned from storage to drainage increased in the studied sandy soil. This reduction in water budget replenishment impacts crops in subsequent growing seasons. Whereas, increased soil freezing had no short-term effects on any of the water budget components in either soil type. This demonstrates soil resilience to short-term increases in soil FTCs.