Variação de atributos hídricos do solo em razão do uso de polímero superbasorvente

Abstract

Several studies have already proven the increase of the water retention capacity in soils using the polymers, but it is still necessary to know how the process of water release at different voltages works. The present study aimed to measure the field capacity (FC) and the available water capacity (CAD) of a sandy soil sample alone and in mixture with the polymer, in a proportion of 5% of the mass. The hypothesis was ventured: 1) The polymer increases the FC, but in a way non-stoichiometric and proportional; 2) The contribution to the increase FC occurs in the powers of 6, 10 and 33 kPa; 3) At lower voltages the water retention of the polymer is higher; 4) The polymer increases the AWC when added to a sandy soil sample. Therefore, the study was composed with three treatments (soil, polymer and sandy soil sample with polymer) in a completely randomized design with 5 replicates. Water retention curves were constructed for all treatments and compared the values of mass base moisture for the field capacity in potentials (6, 10 and 33 kPa) as well as in intervals (6-1500, 10-1500 and 33-1500 kPa) and submitted to the Kruskal-Wallis test (KW) at 5% probability. Therefore, the polymer, in the concentration of 5%, does not promote an increase in the values of humidity in the tensions of 6, 10 and 33 kPa FC values, but causes an increase in CAD values tively.