Use of coarse sand and polyester as envelope material in a drainage system.
Coelho E. F., Oliveira F. das C., Nascimento C. J. A., Lopes L. F. V., Araújo E. C. E.
Author Affiliation: Embrapa Mandioca e Fruticultura, Rua EMBRAPA S/N, CP 07, Cruz das Almas, BA, CEP 44380-000, Brazil.
Revista Brasileira de Engenharia Agrícola e Ambiental 3 : 293-297
Abstract : This study was carried out in Teresina-PI, Brazil, with mangoes cv. Tommy Atkins cultivated under a drainage system during the rainy seasons of 1997 and 1998. The effect of 2 envelope materials (coarse sand and polyester) on the drainage efficiency was evaluated in drains 120 m long, 0.10 m diameter and 35 m apart. The parameters for evaluation were: water table depth, rate of water table drawdown and discharge of water from the drains. The water table monitoring was accomplished by 4 groups of observation wells installed in a line perpendicular to the direction of the drains. Drain discharge was measured by hydrometers. Results showed that higher differences between parameters used to evaluate the envelope material performance were detected during 1997. Higher elevations of water table as a consequence of more intense precipitation were noticed in this year. The use of coarse sand as the envelope material resulted in higher drainage efficiency when compared to polyester.