@article{Concialdi_Bagarello_Alagna_Iovino_2019, title={Laboratory evaluation of falling-head infiltration for saturated soil hydraulic conductivity determination}, volume={51}, url={https://www.agroengineering.org/jae/article/view/1003}, DOI={10.4081/jae.2019.1003}, abstractNote={<p>Falling-head one-dimensional infiltration procedures, such as the simplified falling-head (SFH) technique, yield estimates of saturated soil hydraulic conductivity, <em>K<sub>s</sub></em>, with parsimonious and rapid experiments. Factors that can influence determination of <em>K<sub>s</sub></em> by the SFH technique were tested in the laboratory on three repacked soils differing by particle diameter ranges (0-2000, 0- 105 and 105-2000 mm, respectively). Using the theoretically calculated depth of ponding on the infiltration surface, <em>D</em>, instead of the measured one had a small impact on the <em>K<sub>s</sub></em> calculations (means differing by a factor of 1.1-1.2, depending on the soil). For the finest soil, <em>K<sub>s</sub></em> decreased by 3.1 times as <em>D</em> increased from 40 to 135 mm but <em>D</em> did not affect <em>K<sub>s</sub></em> for the coarsest soil, yielding in general the highest <em>K<sub>s</sub></em> values. The abrupt increase of the infiltration rate close to the end of the run did not influence appreciably <em>K<sub>s</sub></em> calculations since it determined an increase in <em>K<sub>s</sub></em> by a mean factor never exceeding 1.1. The most frequent result of the developed procedure for estimating the α* parameter was failure of the experiment although the valid α* calculations were plausible, being higher for the coarse textured soil (17 m<sup>–1</sup>) than the finer soils (9.2-9.3 m<sup>–1</sup>). The depth of the wetting front at the end of the run was 1.1-1.2 times deeper than that calculated theoretically before the run, depending on the soil. In conclusion, the method used to determine <em>D</em> should not affect very much <em>K<sub>s</sub></em> determination but larger D values can yield smaller <em>K<sub>s</sub></em> values in fine-textured soils. Air escapes from the sampled soil volume when almost all water had infiltrated but this circumstance does not have a great impact on calculation of <em>K<sub>s</sub></em>. A falling-head one-dimensional ponded infiltration process is not recommended to estimate α*. The theoretical depth of the wetting front can approximately be predicted before the run. The SFH technique appears a rather robust method to simply and rapidly determine <em>K<sub>s</sub></em>.</p>}, number={1}, journal={Journal of Agricultural Engineering}, author={Concialdi, Paola and Bagarello, Vincenzo and Alagna, Vincenzo and Iovino, Massimo}, year={2019}, month={Oct.}, pages={27–35} }