A field methodology for measuring the least limiting water range of soils

• Grant number: 12/05596-6
• Support type: Regular Research Grants
• Duration: June 01, 2012 - November 30, 2014
• Field of knowledge: Agronomical Sciences - Agronomy - Soil Science
• Principal researcher: Alvaro Pires da Silva
• Grantee: Alvaro Pires da Silva
• Home Institution: Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Universidade de São Paulo (USP). Piracicaba , SP, Brazil
• Assoc. researchers: Cássio Antonio Tormena ; Getulio Coutinho Figueiredo ; Neyde Fabíola Balarezo Giarola

Abstract

Soil water availability to plants is defined as the amount of water ranging from field capacity and wilting point. Moreover, plant growth may also be modified directly by strength and aeration. So far the Least Limiting Water Range (LLWR) is the only soil physical parameter that integrates the complex interactions between water content and soil structure, which determine the potential of water, gas diffusion and resistance to penetration, and therefore can be used as a suitable indicator of the soil quality for crop growth. LLWR evaluations have been made using essentially laboratory methodologies. However, the evolution of the LLWR concept requires alternative methodologies for its quantification, such as obtaining data directly in the field. The LLWR determined in the field can be a physical parameter more sensitive to differentiate soil management systems in relation to that determined in the laboratory, to represent more accurately the soil physical conditions for plant growth. Therefore, the objective of this project is to compare the LLWR determined with the laboratory methodology with that obtained in the field to assess the sensitivity of these procedures for detecting soil management systems in different soil textural classes. (AU)