Indicador de tensão para tensiômetros de câmara de ar.

Abstract

A low cost alternative for water management is the air chamber tensiometer with direct readings. The objective of this work was to develop a device for water potential measurement in air pocket tensiometers. Devices tested were pieces with length of four and eight centimeters installed in tensiomenter with initial height of air-pocket of two and three centimeters. Another gauge was constituted of a graduated tape. Experimental design was an entirely randomized with three replications. Treatments resulted from a combination of five chamber configurations and three soil types (sandy, loamy and clay). Tensiometers were installed in pots where Bermuda grass was grown. Measures were taken simultaneously with a graduated rule and with a digital tensimeter. Devices more accurate for low potential measurement had the upper section which dimensions prevented capillary raise. One exception was the device with a four centimeter height and initial air-pocket with two centimeter. The other devices were efficient in measuring water potential directly.