Location: Environmental Microbial & Food Safety Laboratory
Title: On soil textural classifications and soil texture-based estimationsAuthor
MARTIN, MIGUEL - Polytechnic University Of Madrid | |
Pachepsky, Yakov | |
GARCIA-GUTIERREZ, CARLOS - Polytechnic University Of Madrid | |
REYES, MIGUEL - Universidad De Cordoba |
Submitted to: Geophysical Research Letters
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 1/23/2018 Publication Date: 2/22/2018 Citation: Martin, M.A., Pachepsky, Y.A., Garcia-Gutierrez, C., Reyes, M. 2018. On soil textural classifications and soil texture-based estimations. Geophysical Research Letters. Solid Earth 9(1):159-165. Interpretive Summary: Contents of the major particle fractions, i.e. sand, silt, and clay, routinely used to characterize soil solids and to estimate various soil properties. Each of these fractions includes particles having sizes within specific ranges. The hypothesis of this work was that the size ranges should be changed depending on which soil property needs to be estimated. A large database of Florida soils was used, and the properties to estimate were detailed particle size distribution and the soil bulk density. We found that indeed the best estimation required changes in particle size ranges. The best detailed particle size distributions were obtained by combining silt and clay in a single fraction, and defining fine sand and very fine sand as a separate intermediate size fraction. The best estimation of bulk density also required changing size boundaries of the intermediate fraction. Much better estimates could be obtained using the data on sand subfractions that are readily available but have not been used before. Results of this work can be used in wide range of environmental applications where soil particle size distributions are used to estimate soil properties. Technical Abstract: The soil texture representation with the standard textural fraction triplet 'sand-silt-clay' is commonly used to estimate soil properties. The objective of this work was to test the hypothesis that other fraction sizes in the triplets may provide better representation of soil texture for estimating some soil parameters. We estimated the cumulative particle size distribution and bulk density from entropy-based representation of the textural triplet with experimental data for 6300 soil samples. Results supported the hypothesis. For example, simulated distributions were not significantly different from the original ones in 25 and 85% of cases when the 'sand-silt-sand' and 'very coarse+coarse + medium sand - fine +very fine sand - silt+clay', were used, respectively. When the same standard and modified triplets were used to estimate the average bulk density, the coefficients of determination were 0.001 and 0.967, respectively. Overall, the textural triplet selection appears to be application- and data-specific. |