@Article{NegrónJuárezFMFMCROAWNGVABTHC:2020:CaMeCh,
               author = "Negr{\'o}n'Ju{\'a}rez, Robinson and Ferreira, Savio J. F. and 
                         Mota, Marcelo Crestani and Faybishenko, Boris and Monteiro, Maria 
                         Terezinha F. and Candido, Luiz A. and Ribeiro, Rubia Pereira and 
                         Oliveira, Regison Costa and Araujo, Alessandro C. and Warren, 
                         Jeffrey M. and Newman, Brent D. and Gimenez, Bruno O. and 
                         Varadharajan, Charuleka and Agarwal, Deborah and Borma, Laura de 
                         Simone and Tomasella, Javier and Higuchi, Niro and Chambers, 
                         Jeffrey Q.",
          affiliation = "{Lawrence Berkeley National Laboratory} and {Instituto Nacional de 
                         Pesquisas da Amaz{\^o}nia (INPA)} and {Instituto Nacional de 
                         Pesquisas da Amaz{\^o}nia (INPA)} and {Lawrence Berkeley National 
                         Laboratory} and {Instituto Nacional de Pesquisas da Amaz{\^o}nia 
                         (INPA)} and {Instituto Nacional de Pesquisas da Amaz{\^o}nia 
                         (INPA)} and {Instituto Nacional de Pesquisas da Amaz{\^o}nia 
                         (INPA)} and {Instituto Nacional de Pesquisas da Amaz{\^o}nia 
                         (INPA)} and {Empresa Brasileira de Pesquisa Agropecu{\'a}ria 
                         (EMBRAPA)} and {Oak Ridge National Laboratory} and {Los Alamos 
                         National Laboratory} and {Instituto Nacional de Pesquisas da 
                         Amaz{\^o}nia (INPA)} and {Lawrence Berkeley National Laboratory} 
                         and {Lawrence Berkeley National Laboratory} and {Instituto 
                         Nacional de Pesquisas Espaciais (INPE)} and {Centro Nacional de 
                         Monitoramento e Alertas de Desastres Naturais (CEMADEN)} and 
                         {Instituto Nacional de Pesquisas da Amaz{\^o}nia (INPA)} and 
                         {Lawrence Berkeley National Laboratory}",
                title = "Calibration, measurement, and characterization of soil moisture 
                         dynamics in a central Amazonian tropical forest",
              journal = "Vadose Zone Journal",
                 year = "2020",
               volume = "19",
               number = "1",
                pages = "1--16",
             keywords = "soil moisture, Central Amazon, in situ measurements.",
             abstract = "Soil moisture plays a key role in hydrological, biogeochemical, 
                         and energy budgets of terrestrial ecosystems. Accurate soil 
                         moisture measurements in remote ecosystems such as the Amazon are 
                         difficult and limited because of logistical constraints. Time 
                         domain reflectometry (TDR) sensors are widely used to monitor soil 
                         moisture and require calibration to convert the TDRs dielectric 
                         permittivity measurement (Ka) to volumetric water content 
                         (\θv). In this study, our objectives were to develop a 
                         field-based calibration of TDR sensors in an old-growth upland 
                         forest in the central Amazon, to evaluate the performance of the 
                         calibration, and then to apply the calibration to determine the 
                         dynamics of soil moisture content within a 14.2-m-deep vertical 
                         soil profile. Depth-specific TDR calibration using local soils in 
                         a controlled laboratory setting yielded a novel Ka\θv 
                         third-degree polynomial calibration. The sensors were later 
                         installed to their specific calibration depth in a 14.2-m pit. The 
                         widely used Ka\θv relationship (Topp model) underestimated 
                         the site-specific \θv by 2242%, indicating significant error 
                         in the model when applied to these well-structured, clay-rich 
                         tropical forest soils. The calibrated wet- and dry-season 
                         \θv data showed a variety of depth and temporal variations 
                         highlighting the importance of soil textural differentiation, root 
                         uptake depths, as well as event to seasonal precipitation effects. 
                         Data such as these are greatly needed for improving our 
                         understanding.",
                  doi = "10.1002/vzj2.20070",
                  url = "http://dx.doi.org/10.1002/vzj2.20070",
                 issn = "1539-1663",
                label = "lattes: 1192267190424956 15 
                         Negr{\'o}nJu{\'a}rezFMFMCROAWNGVABTHC:2020:CaMeCh",
             language = "en",
           targetfile = "negron_calibration.pdf",
        urlaccessdate = "28 abr. 2024"
}