author = "Borma, Laura de Simone and Lima, Jos{\'e} Romualdo and Ometto, 
                         Jean Pierre Henry Balbaud",
          affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and 
                         {Universidade Federal Rural de Pernambuco (UFRPE)} and {Instituto 
                         Nacional de Pesquisas Espaciais (INPE)}",
                title = "Soil moisture variation along a toposequence in the northeast 
                         Brazilian caatinga",
                 year = "2019",
         organization = "EGU General Assembly",
             abstract = "Soil moisture variations and soil water potentials are crucial to 
                         understand the plant behavior under water stress conditions. Such 
                         kind of data are also valuable for modeling efforts in hydrology, 
                         ecophysiology, soil-plantatmosphere interactions and earth system 
                         models. Here we present soil moisture variation along the 
                         hydrological year of 2015 for 4 different soil profiles along a 
                         topographic gradient in the Brazilian caatinga, Sao Joao site, 
                         northeast Brazil, Pernambuco state. The data were collected using 
                         Sentek probes, Enviroscan type, in sandy soil profiles of 0.4 m 
                         (P1), 0.5 m (P2), 0.9 m (P3) and 1.10 m (P4), from the bottom to 
                         the top of an instrumented hillslope of around 1 km length. Along 
                         this topographic gradient, the maximum depth of probes 
                         installation occurred due to the existence of an impenetrable 
                         layer, commonly found in some areas of the Caatinga biome. Our 
                         results show that, during the rainy season, in the deepest soil 
                         profile (P4) from the upper part of the slope, soil moisture 
                         reached the maximum of 16% at the top layer (0.1-0.4 m soil 
                         depths), while below 0.4 m depth, the maximum soil moisture 
                         registered during rainy season were 6%. However, during the dry 
                         period, soil moisture at the top (0.1-0.4 m soil depths) decreased 
                         to values below 1 %, while the deeper soil layers (below 0.70 m) 
                         maintained moisture content at values around 4% for the whole dry 
                         period. In the shallower soil profile (P4), soil moisture also 
                         reached the maximum of 16% in the wet season along the whole soil 
                         profile. In the dry period, however, the top layer presented 
                         maximum soil content of 1% while the bottom (0.4 m) maintain 
                         moisture content of around 4%, similar to the deepest layer of the 
                         P4 profile. Similar behavior was found for the intermediate soil 
                         profiles (P2 and P3), suggesting that, independently of the depth 
                         of the soil profile, soil moisture at the interface 
                         soil/atmosphere present values below 1% in the dry season while at 
                         the interface sandy soil/impenetrable layer, moisture is 
                         maintained at around 3-5%. For the next steps, these results will 
                         be analyzed in terms of rainfall rates, soil physical properties 
                         and water storage in order to understand the water balance dynamic 
                         for different soil depths above the impenetrable soil layer.",
  conference-location = "Vienna, Austria",
      conference-year = "07-12 apr.",
             language = "en",
           targetfile = "EGU2019-18249-1.pdf",
        urlaccessdate = "14 abr. 2021"