Parametric pedotransfer functions for predicting soil water retention in a Ngerengere Subcatchment, Morogoro -Tanzania

The soil water retention-release characteristics (SWRC) are essential to understand water redistribution in agricultural systems. However, direct measurements of SWRC are constrained by costs, scarcity of equipment and time. Pedotransfer functions (PTFs) are proposed as a simplified indirect alternative. The gist of this work was to assess the efficacy of selected parametric PTFs for prediction of SWRC based on the Van Genuchten parameters (θs, α, n). Lowest prediction bias was for ès (ME; 0.0574 to 0.1249cm3cm-3). Greatest prediction bias was for n (ME; -0.659 to 0.8521). The PTFs showed low reliability (R2 <15%) necessitating development of locally calibrated PTFs.
Les caractéristiques de rétention-libération de l’eau du sol(SWRC) sont essentielles pour comprendre la redistribution de l’eau dans les systèmes agricoles. Cependant, des mesures directes des SWRC sont contraintes par des coûts, la pénurie de l’équipement et le temps. Les fonctions de transfert de sol (PTFs) sont proposées comme alternative indirecte simplifiée. L’essentiel de ce travail était d’évaluer l’efficacité de PTFs paramétriques choisies pour la prévision des SWRC basées sur les paramètres de Van Genuchten (qs, a, n). La plus basse polarisation de prévision était prévue (ME; 0.0574 à 0.1249cm3cm-3). La plus grande polarisation de prévision était pour n (ME; -0.659 à 0.8521). Les PTFs ont montré la faible fiabilité (R2 <15%) nécessitant le développement des PTFs localement calibrés.
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Region Focus: 
East Africa
RUFORUM Conferences and Workshops
Licence conditions: 
Open Access
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Printed resource

About the RUFORUM 2010 Biennal Conference
"The 2010 RUFORUM Biennial Conference was the second in the series. The main objective of the Biennial conferences is to provide a platform for agricultural research for development stakeholders in Africa and beyond to actively exchange findings and experiences, while at the same time learning lessons towards improving performance of the agricultural sector and ultimately people’s livelihoods. The biennial conference is RUFORUM’s most comprehensive meeting for the diversity of stakeholders in agriculture. It is especially dedicated to graduate students and their supervisors, grantees in RUFORUM member universities and alumni. It is a platform for peer review, quality control, mentorship, networking and shared learning. This record contains an extended abstract accepted under the theme of Natural Resource Management"