15 results

Performance of a tensiometer, TDR and neutron probe for determining soil water and soil hydraulic conductivity

Claudia Fernanda Almeida Teixeira, Sergio Oliveira Moraes, Marcia Aparecida Simonete

01/Apr/2005

The evaluation of agronomic instrumentation to determine soil water content is very important for scientific research. Regardless of the technique in use, it is important that the soil water content is determined easily and quickly for the determination of the function K(q), e.g. With the objective of comparing the performance of the equipments neutron probe and TDR with a tensiometer at determining variations in the soil water content and the values of soil hydraulic conductivity obtained from the soil water […]

Field capacity of Oxisols and Quartzipsamments calculated from moisture equivalent determination

H. A. Ruiz, G. B. Ferreira, J. B. M. Pereira

01/Apr/2003

Soil moisture content, determined by the moisture equivalent method (ME), is associated with field capacity (FC) in temperate soils. The FC matric potential of soils developed under tropical and humid conditions has higher values, in the range of -10 to -6 kPa. To establish a relationship between FC of Oxisols and Quartzipsamments with ME a review of M.S. and Ph.D. theses submitted to the faculty of the Federal University of Viçosa, Brazil, was done. Appropriate data should include soil classification, clay […]

Water retention in two oxisols under different uses

A. N. Beutler, J. F. Centurion, Z. M. Souza, I. Andrioli, C. G. Roque

01/Sep/2002

For every type of soil, the water retention curve is specific and depends on several soil features. This study was carried out to evaluate the influence of soil attributes on water retention in Red Latosol (Haplustox) and Red Latosol (Eutrustox) under different management and use systems. The use systems were: cotton, sugar-cane and woods. The granulometric composition, bulk density, organic matter, Fe2O3 and Al2O3 contents, as well as the water retention curve were determined for soil samples from different depths […]

Incorporation of the bulk density to two models adjusted to the soil water retention curve

C. A. Tormena, A. P. Silva

01/Jun/2002

The soil water retention curve plays a fundamental role in the development of studies on the dynamics of soil water, modeling of physical soil processes and plant growth. The retention curve is usually obtained by simultaneously measuring water content (θ) and soil water potential (ψ) in a single sample. An alternative procedure is to use several samples per ψ to describe the retention curve. The use of this procedure requires that the variation factors which exist among the samples are […]

Soil water availability to maize plants cultivated in soils with different textures

R. Carlesso, R. F. Santos

01/Mar/1999

The objectives of this experiment were to identify differences in the total quantity of water stored in soil, storing capacity of water available to the plants and in the water consumption of maize plants cultivated in soils of different textures. The experiment was conducted at the experimental area of the Rural Engineering Department of the Federal University of Santa Maria during the 1995/1996 growing season. A set of 12 drainage lysimeters was used. These were 156 cm long, 100 cm wide and 80 cm […]

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