A test of water pouring height and run intermittence effects on single‐ring infiltration rates

Abstract

Assessing how the infiltration process depends on the water impact energy improves interpretation of hydrological processes. Impact energies vary with the height of water pouring; that is, the distance between the water delivery point and the soil surface. The effects of the height of water pouring on infiltration in an initially near saturated soil can be tested in the field by two repeated Beerkan infiltration runs separated by a short pause (30 min) and using both low (non‐perturbing) and high (perturbing) heights of water application. The double two‐stage Beerkan run methodology was applied in two soils. The infiltration rate at the end of the perturbing stage of the experiment was 0.2–0.3 (sandy‐loam soil) and 0.15 (loam soil) times that obtained with the initial, nonperturbing stage whereas, without any perturbing effect, infiltration rates at the end of the second run were 0.5 times those at the end of the first run. Therefore, the methodology distinguished between a decrease in infiltration rate due to water redistribution during the pause and that attributable to soil surface perturbation. Maintaining a small depth of water (10 mm) on the infiltration surface was not an alternative to the classical Beerkan run for the non‐perturbing stage of the experiment since two times higher infiltration rates were measured with a greater hydrostatic pressure. In conclusion, the relationship between infiltration into an initially near saturated soil and the energy of the applied water can be determined directly in the field at any time with a simple and parsimonious experiment. This circumstance could improve soil hydraulic characterization for interpreting and simulating hydrological processes.

Correspondence between theory and practice of a Beerkan infiltration experiment

“…For each soil and ring radius, the d1H0 setup yielded smaller i r / K s values as compared with the theoretical d0H0 setup, as shown in the three examples of Figure 2, confirming that the initial 1D stage made infiltration slower as compared with the completely unconfined process (Dušek et al., 2009) and also demonstrating that a ring insertion by only 1 cm was enough to make this slow down perceivable. On the other hand, the d0H1 setup yielded higher i r / K s values than the theoretical setup, because the pressure head gradient was greater in the former case (Alagna et al., 2018; Dušek et al., 2009). As expected, the normalized infiltration rates for the d1H1 setup fell into the area bounded by the curves corresponding to the d1H0 and d0H1 setups.…”

Improved Beerkan run methodology to assess water impact effects on infiltration and hydraulic properties of a loam soil under conventional‐ and no‐tillage

“…Therefore, the applied methodology appeared appropriate to perceive the manner in which water pouring height influenced the soil properties. This result was novel because all previous tests of the Beerkan run methodology were carried out by comparing a non-perturbing run with a single-perturbing run (e.g., Alagna et al, 2016Alagna et al, , 2018Bagarello, Castellini, et al, 2014).…”

“…Infiltration experiments were summarized by plotting the individual relationships between infiltration rate, i r (mm h −1 ) and cumulative infiltration, I (mm), according to Alagna et al. (2018). The mean infiltration time, Δ t (T), of each applied water volume (1 st , 2 nd , …, 15 th ) was calculated for the L, M, and H runs.…”

“…According to some recent investigations, however, single‐ring infiltration methods appear usable to both test water impact effects on infiltration and determine the hydraulic properties of a soil in which the upper layer deteriorates (Alagna, Bagarello, Cecere, Concialdi, & Iovino, 2018; Alagna et al., 2019; Auteri, Bagarello, Concialdi, & Iovino, 2020; Bagarello, Castellini, Di Prima, & Iovino, 2014; Bagarello, Cecere, Di Prima, Giordano, & Iovino, 2017; Bagarello, Cecere, David, & Di Prima, 2020). In particular, ponding infiltration experiments of the Beerkan type (Lassabatère et al., 2006) can be performed with different heights of water pouring (e.g., low [L], and high [H], equal to 3 and 150 cm, respectively) to mimic rainfall impact effects (null and appreciable, respectively) on the soil surface.…”

Water transmission properties of a sandy-loam soil estimated with Beerkan runs differing by the infiltration time criterion

“…Errors in visual estimation of tm could occur, as also mentioned by Smith (1999). With the to criterion, the infiltration process is steadily performed under a small, but non-null ponded head of water (Alagna et al, 2018) although the infiltration model proposed by Haverkamp et al (1994) is strictly valid for a null ponded depth of water on the infiltration surface. The effect of the ITC for a classical Beerkan run on the soil water transmission properties estimated with BEST is unknown.…”