Measuring and Modeling Macroporous Soil Water and Solute Flux Below the Root Zone of a Plano Silt-Loam Soil

Background/Need: Groundwater is a very important natural resource in Wisconsin, much of the United States, and throughout the world. While being the main source for drinking water, it is heavily used in various industries and agriculture for irrigation. Thus, rapid groundwater recharge is important. While groundwater is recharged rapidly via water flowing through macropores, especially in fine textured soils, there are some negative impacts associated with this rapid recharge. The impact of water and solutes flowing through macropores on groundwater quantity and quality is known to be significant, yet it remains poorly understood, and there are limited models available to simulate this. In addition to a lack of good simulation models, methods for real time sampling of macroporous water and solute fluxes are limited as well.

Objectives: (a) Measure macroporous water and solute flow in-situ in a well drained silt loam soil under varying conditions, and (b) to use the data to derive critical parameters of macropore simulation models.