Autoria: MACIEL, D. A.; SILVA, V. A.; ALVES, H. M. R.; VOLPATO, M. M. L.; BARBOSA, J. P. R. A. de; SOUZA, V. C. O.; SANTOS, M. O.; SILVEIRA, H. R. DE O.; DANTAS, M. F.; FREITAS, A. F. de; SANTOS, J. O. DOS

Resumo: Traditionally, water conditions of coffee areas are monitored by measuring the leaf water potential throughout a pressure pump. However, there is a demand for the development of technologies that can estimate large areas or regions. In this context, the objective of this study was to estimate the WW by surface reflectance values and vegetation indices obtained from the Landsat-8/OLI sensor in Minas Gerais-Brazil Several algorithms using OLI bands and vegetation indexes were evaluated and from the correlation analysis, a quadratic algorithm that uses the Normalized Difference Vegetation Index (NDVI) performed better, with a correlation coefficient (R2) of 0.82. Leave-One-Out Cross-Validation (LOOCV) was performed to validate the models and the best results were for NDVI quadratic algorithm, presenting a Mean Absolute Percentage Error (MAPE) of 27.09% and an R2 of 0.85. Subsequently, the NDVI quadratic algorithm was applied to Landsat-8 images, aiming to spatialize the WW estimated in a representative area of regional coffee planting between September 2014 to July 2015. From the proposed algorithm, it was possible to estimate WW from Landsat-8/OLI imagery, contributing to drought monitoring in the coffee area leading to cost reduction to the producers.

Ano de publicação: 2020

Tipo de publicação: Artigo de periódico

Unidade: Embrapa Café

Palavras-chave: Café, Coffee beans, Leaf water potential, Plantations, Potencial Hídrico, Produção Agrícola, Remote sensing, Área Foliar