Pedotransfer functions to estimate hydraulic properties of tropical Sri Lankan soils

A Functional Analysis of Pedotransfer Functions Developed for Sri Lankan soils: Applicability for Process-Based Crop Models

“…Point PTFs were developed [5] for Sri Lankan soil and confirmed the statistical accuracy of these PTFs for Sri Lankan conditions. However, these PTFs cannot perfectly calculate soil hydraulic parameters.…”

“…Point-based PTFs are used to determine soil parameters at specific, conventional values of matric potential [3]. The moisture content at −10 and −33 kPa (representing the field capacity (FC)) and moisture content at -1500 kPa (representing the permanent wilting point (PWP)) are the most common reference values for the soil moisture characteristic curve (SMCC) used for point PTFs [4].Point PTFs were developed [5] for Sri Lankan soil and confirmed the statistical accuracy of these PTFs for Sri Lankan conditions. However, these PTFs cannot perfectly calculate soil hydraulic parameters.…”

“…Some authors have discussed the importance of functional analysis for the uses of PTFs and have reported the importance of functionally evaluating PTFs for real field-scale applications [7,9,12,13].One of the most popular applications of PTFs is using model simulations for environmental and crop processes. Studies have been conducted to evaluate the functionality of PTFs for environmental simulations, such as water flow simulations [13][14][15][16][17], evapotranspiration simulations, water balance studies [10,11,18,19], and irrigation water estimations [5,20], using different models. However, no such comprehensive studies have been conducted for process-based crop models [5].Process-based crop models derive their output based on soil, climate, plant, and management parameters; therefore, the accuracy model output depends on the accuracy of the input parameters.…”

“…Studies have been conducted to evaluate the functionality of PTFs for environmental simulations, such as water flow simulations [13][14][15][16][17], evapotranspiration simulations, water balance studies [10,11,18,19], and irrigation water estimations [5,20], using different models. However, no such comprehensive studies have been conducted for process-based crop models [5].Process-based crop models derive their output based on soil, climate, plant, and management parameters; therefore, the accuracy model output depends on the accuracy of the input parameters. At present, the acquisition of historic climate information for specific locations is easy due to the availability of ground-level observations and grid-based generated datasets.…”

“…One of the most popular applications of PTFs is using model simulations for environmental and crop processes. Studies have been conducted to evaluate the functionality of PTFs for environmental simulations, such as water flow simulations [13][14][15][16][17], evapotranspiration simulations, water balance studies [10,11,18,19], and irrigation water estimations [5,20], using different models. However, no such comprehensive studies have been conducted for process-based crop models [5].…”