Decagon recently compared the DualHead Infiltrometer (15.24 cm inner ring diameter) with a double-ring infiltrometer (15.24 cm inner ring, 30.48 cm outer ring diameter) We conducted the test at 7 locations distributed across a turf field (Fig. 1).
Measurements were collected at the same time within the same 1 m2 area. The DualHead and double-ring infiltrometer measurements compared well, except in cases where the flow was dominated by large macropores (Fig. 2).
Large macropores primarily dominated measurements at locations SF3 and SF4. At these locations, we hypothesise that the amount of force required to install the double-ring infiltrometer disturbed the structure of the soil and crushed the macropores. Because of this disturbance, the field saturated hydraulic conductivity (Kfs) from the double-ring infiltrometer was 2 orders of magnitude lower than the DHI measurements (Table 1).
Overall, the two methods provided similar estimates of saturated hydraulic conductivity, except in cases where there are large structural macropores that can be destroyed when subjected to the amount of force required to install the double-ring infiltrometer