Pedosphere 23(6): 779--789, 2013
ISSN 1002-0160/CN 32-1315/P
©2013 Soil Science Society of China
Published by Elsevier B.V. and Science Press
| Field and numerical tests of the two-ponding depth procedure for analysis of single-ring pressure infiltrometer data |
V. BAGARELLO1, M. IOVINO1 and LAI Jian-Bin2 |
1Dipartimento dei Sistemi Agro-Ambientali, Università degli Studi di Palermo, Viale delle Scienze, Palermo 90128 (Italy)
2Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101 (China) |
| ABSTRACT |
| The two-ponding depth (TPD) analysis procedure of single-ring infiltrometer data can yield invalid results, i.e., negative values of the field-saturated soil hydraulic conductivity or the matric flux potential, denoting failure of the two-level run. The objective of this study was to test the performance of the TPD procedure in analyzing the single-ring infiltrometer data of different types of soils. A field investigation carried out in western Sicily, Italy, yielded higher failure rates (40%) in two clay loam soils than in a sandy loam soil (25%). A similar result, i.e., fine-textured soils yielding higher failure rates than the coarse-textured one, was obtained using numerically simulated infiltration rates. Soil heterogeneity and reading errors were suggested to be factors determining invalid results in the field. With the numerical data, allowing a less generic definition of soil heterogeneity, invalid TPD results were occasionally obtained with the simultaneous occurrence of a high random variation (standard deviation ≥ 0.5) and a well developed structural correlation for saturated hydraulic conductivity (correlation length ≥ 20 cm). It was concluded that a larger number of replicated runs should be planned to characterize fine-textured soils, where the risk to obtain invalid results is relatively high. Large rings should be used since they appeared more appropriate than the small ones to capture and average soil heterogeneity. Numerical simulation appeared suitable for developing improved strategies of soil characterization for an area of interest, which should also take into account macropore effects. |
| Key Words: field-saturated hydraulic conductivity, infiltration rate, numerical simulation, soil heterogeneity, soil texture |
| Citation: Bagarello, V., Iovino, M. and Lai, J. B. 2013. Field and numerical tests of the two-ponding depth procedure for analysis of single-ring pressure infiltrometer data. Pedosphere. 23(6): 779-789. |
|
View Full Text
|
|
|
|
