Quantifying rate of water infiltration in soil in a Hawai‘i forest

Water level changing in an infiltrometer used to measure the rate of water infiltration into the soil. Infiltration rates were measured across forest sites in Hawai‘i. The red coloring was used in some sites where infiltration was slow enough that camera systems were used to log the rate of water level drop over time. In those automated measurements, the red food-grade dye made identification of the water level from digital images easier.