Comportamento da umidade no solo por meio de sensores de resistência elétrica sob cobertura vegetal de eucalipto e de essências florestais nativas

Abstract

This article presents the results of a study aimed at evaluating the behavior of water in the soil based on measurements of humidity in the soil profile. Soil humidity data were acquired in the period between June 16 and September 08, 2009, using a set of 96 Watermark TM sensors installed at three soil depths, 20, 60, and 120 cm and in two plots. One plot (with 48 sensors) located in a four-year old Eucalyptus area and the other plot located in an adjacent native forest area. Both plots have the same slope and aspect characteristics. Soil physical and chemical characteristics were determined at the laboratory using collected samples. Results indicate that under Eucalyptus cover at the intermediate soil layer (60 cm) the humidity conditions is more stable. When precipitation occurs the top and intermediate layers respond more rapidly and the deeper layer requires more time to respond. Comparison between Eucalyptus and native forest cover indicate that forest cover had consistently higher water content in the soil at all three depth layers in this short term of observation.