Abstract

FERRAREZI, Rhuanito Soranz et al. Water depth, filling time and volume of wick irrigation equipment and determination of water distribution uniformity in substrates. Bragantia [online]. 2012, vol.71, n.2, pp. 273-281.  Epub July 13, 2012. ISSN 0006-8705.  http://dx.doi.org/10.1590/S0006-87052012005000015.

The aims of this study were to evaluate the water depth, filling time and volume in a wick irrigation equipment using auto compensating gutters and to determine the water distribution uniformity (WDU) in these equipments filled with organic commercial substrates (pine bark/PB and coconut coir/CC). We assembled two experimental modules in a completely randomized design with five replications. There was variation in water depth measurements (1.6 to 4.0 cm), even with the equipment leveled. Average filling time was 6h22min for Module 1 with PB and 3h45min for Module 2 with CC. The filling volume was variable, showing that gutters in the extremities (No. 1 and 5) had lower volumes in Module 1 and in the beginning (No. 1 and 2) in Module 2. Volumetric soil moisture (θ) ranged from 42 to 94% in Module 1 and from 24 to 72% in Module 2, with isolated points of desiccation and/or flooding. Water depth, filling time and volume were disuniform in all experimental modules and auto compensating gutters, indicating equipment imperfections. Water distribution was variable in both substrates due to their hydro-physical characteristics and also water depth in the gutters, with higher humidity and water distribution uniformity in pine bark than in coconut coir.

Keywords : capillarity; coconut coir; pine bark; subirrigation.