Variability of soil hydraulic properties throughout an annual crop growing cycle and its effect on available water and water balance components

• Grant number: 25/11249-7
• Support Opportunities: Scholarships in Brazil - Master
• Start date: October 01, 2025
• End date: July 31, 2027
• Field of knowledge: Agronomical Sciences - Agronomy - Soil Science
• Principal Investigator: Quirijn de Jong van Lier
• Grantee: Tainara Perciliano da Silva
• Host Institution: Centro de Energia Nuclear na Agricultura (CENA). Universidade de São Paulo (USP). Piracicaba , SP, Brazil
• Associated research grant: 24/13218-9 - Plant available water in Brazilian soils: assessment of its lower limit by a process-based transpiration reduction function, AP.R

Abstract

This MSc project focuses on evaluating the effect of the temporal variation of soil hydraulic properties on the prediction of water balance components and plant-available water. The specific objectives are to determine the soil hydraulic properties under no-tillage throughout the crop cycle, and to assess the effect of their variation on water balance predictions and the estimation of plant-available water. The water balance components will be estimated using the agro-hydrological model SWAP, while plant-available water will be estimated using the flux-based method (FBM). The experimental basis of the project consists of a soybean field experiment conducted in Piracicaba, SP, Brazil. Soil hydraulic properties (water retention and hydraulic conductivity) will be determined at five different stages of the soybean growing cycle and at several soil depths. The results will be used to determine the sensitivity of plant-available water and water balance components to variations in these properties. The findings may provide valuable insights to support decision-making in agronomy, including irrigation and drainage management, crop production, and soil and water conservation.