@Article{NogueiraMoreVolp:2018:ReCoCr,
               author = "Nogueira, Sulimar Munira Caparoci and Moreira, Maur{\'{\i}}cio 
                         Alves and Volpato, Margarete M. L.",
          affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and {Instituto 
                         Nacional de Pesquisas Espaciais (INPE)} and {Empresa de Pesquisa 
                         Agropecu{\'a}ria de Minas Gerais (EMBRAPA)}",
                title = "Relationship between coffee crop productivity and vegetation 
                         indexes derived from oli / landsat-8 sensor data with and without 
                         topographic correction",
              journal = "Engenharia Agr{\'{\i}}cola",
                 year = "2018",
               volume = "38",
               number = "3",
                pages = "387--394",
                month = "maio/jun.",
             keywords = "coffee, NDVI, NDWI, yield, SAVI, remote sensing.",
             abstract = "The reflectance values of a coffee crop are influenced by several 
                         factors such as planting direction, crop spacing, time of the 
                         year, plant age and topography which reduces the accuracy of the 
                         estimates derived from remote sensing data. In this context were 
                         evaluated the relationships between coffee productivity and values 
                         of NDVI, SAVI and NDWI vegetation indexes with and without 
                         topographic reflectance correction for different coffee 
                         phenological phases for the crop years 2013/2014 (low 
                         productivity) and 2014/2015 (high productivity). The evaluations 
                         were made through the standard deviation of vegetation indices 
                         (VIs), linear relationship between the cosine factor and the VIs 
                         and between VIs and coffee productivity. The best phenological 
                         phases of coffee to determine productivity from spectral indexes 
                         were the stages of dormancy and flowering. The results indicated 
                         that the NDVI was the best index to estimate the productivity of 
                         coffee trees with coefficient of determination (Rē) that ranged 
                         from 0.58 to 0.90. There was an increase in Rē between 
                         productivity and NDVI with topographic correction in the dormancy 
                         phase in the year of low productivity; between productivity and 
                         NDVI with topographic correction in the flowering phase in the 
                         year of high productivity; and between productivity and SAVI and 
                         NDWI with topographic corrections in the flowering phase in the 
                         year of high productivity.",
                  doi = "10.1590/1809-4430-Eng.Agric.v38n3p387-394/2018",
                  url = "http://dx.doi.org/10.1590/1809-4430-Eng.Agric.v38n3p387-394/2018",
                 issn = "0100-6916",
             language = "en",
           targetfile = "nogueira_relationship.pdf",
        urlaccessdate = "27 abr. 2024"
}