Pedotransfer in soil physics: trends and outlook — A review —

Abstract

Parameters governing the retention and movement of water and chemicals in soils are notorious for the difficulties and high labor costs involved in measuring them. Often, there is a need to resort to estimating these parameters from other, more readily available data, using pedotransfer relationships.This work is a mini-review that focuses on trends in pedotransfer development across the World, and considers trends regarding data that are in demand, data we have, and methods to build pedotransfer relationships. Recent hot topics are addressed, including estimating the spatial variability of water contents and soil hydraulic properties, which is needed in sensitivity analysis, evaluation of the model performance, multimodel simulations, data assimilation from soil sensor networks and upscaling using Monte Carlo simulations. Ensembles of pedotransfer functions and temporal stability derived from "big data" as a source of soil parameter variability are also described.Estimating parameter correlation is advocated as the pathway to the improvement of synthetic datasets. Upscaling of pedotransfer relationships is demonstrated for saturated hydraulic conductivity. Pedotransfer at coarse scales requires a different type of input variables as compared with fine scales. Accuracy, reliability, and utility have to be estimated independently. Persistent knowledge gaps in pedotransfer development are outlined, which are related to regional soil degradation, seasonal changes in pedotransfer inputs and outputs, spatial correlations in soil hydraulic properties, and overland flow parameter estimation.Pedotransfer research is an integral part of addressing grand challenges of the twenty-first century, including carbon stock assessments and forecasts, climate change and related hydrological weather extreme event predictions, and deciphering and managing ecosystem services.

Predicting available water of soil from particle-size distribution and bulk density in an oasis–desert transect in northwestern China

“…Overviews of the current status of PTF approaches have been given by Wösten et al (2001) and Gijsman et al (2003). Pachepsky et al (2015) comprehensively summarized the trends in PTF development and in input and output data, and methods to build PTFs. Various PTFs are usually given in the form of either a tabulation (Schaap and Leij, 1998;Soet and Stricker, 2003;Al Majou et al, 2008) or continuous functions (Wösten et al, 1999;Bayat et al, 2013;Haghverdi et al, 2015) to predict either a single point on the SWCC (Skaggs et al, 2001;Ramos et al, 2014) or parameters for the entire SWCC (Schaap et al, 2001).…”

Why We Should Include Soil Structural Dynamics of Agricultural Soils in Hydrological Models

“…For instance, pedotransfer functions (PTF) are empirical relationships between models of soil parameters and easily available proxy variables on soil properties. Though they have become an indispensable tool for modeling soil processes, their ability to capture spatio-temporal dynamics of soil properties have been under debate [32].…”

Folyadék-visszatartás, folyadékvezetés és porozitás összefüggései vízzel és/vagy szerves folyadékkal telített talajokban I. Folyadék-visszatartó képesség — Szemle

“…pedotranszfer függvényekkel (pedotransfer function -PTF). A PTF-ek képzésének lehetősége kezdetben számos szakterületen újdonságot jelentett, legjelentősebb előrelépés azonban a talaj hidraulikai jellemzői-nek becslésében történt (PACHEPSKY et al, 2015). Mára már számos olyan adatbá-zist hoztak létre, amelyek alkalmasak a PTF-ek képzésére, fejlesztésére és a hidraulikai jellemzők becslésének alapját jelenthetik (HYPRES -WÖSTEN et al A mintázat-felismerésen (discovering pattern in data) alapuló ún.…”

“…Hogyan határozható meg a modellek bemeneti és kimeneti paramétereinek minősége, az adatállományból eredő bizonytalanság és a modell bizonytalansága? Kérdéses továbbá a PTF-ekkel végzett becslés léptékfüggése, ígéretes kutatási terü-let a paraméterek közötti összefüggések feltárása, a szintetikus adatállományok fejlesztése és a különböző léptékű becslések megfelelő bemeneti változóinak megválasztása is (PACHEPSKY et al, 2015).…”