Analysis of evapotranspiration and biomass in pastures with degradation indicatives in the Upper Tocantins River Basin, in Brazilian Savanna

Abstract

The objective of this study was to apply the Simple Algorithm For Evapotranspiration Retrieving (SAFER) with MODIS images together with meteorological data to analyze evapotranspiration (ET) and biomass production (BIO) according to indicative classes of pasture degradation in Upper Tocantins River Basin. Indicative classes of degraded pastures were obtained from the NDVI time-series (2002-2012). To estimate ET and BIO in each class, MODIS images and data from meteorological stations of the year 2012 were used. The results show that compared to not-degraded pastures, ET and BIO were different in pastures with moderate to strong degradation, mainly during water stress period. Therefore, changes in energy balance partition may occur according to the degradation levels, considering that those indicatives of degradation processes were identified in 24% of the planted pasture areas. In this context, ET and BIO estimates using remote sensing techniques can be a reliable indicator of forage availability, and large-scale aspects related to the degradation of pastures. It is expected that this knowledge may contribute to initiatives of public policies aimed at controlling the loss of production potential of pasture areas in the Upper Tocantins River Basin in the state of Goiás, Brazil.

Evapotranspiration mapping of commercial corn fields in Brazil using SAFER algorithm

“…Very few studies have been published in the scientific literature with SAFER algorithm involving large areas with monocultures under full irrigation (e.g., corn) in semiarid regions. Most studies available to the scientific community were conducted in large areas involving different crops, cultivation systems, and edaphoclimatic conditions (Andrade et al, 2016;Coaguila et al, 2017;Dehziari and Sanaienejad, 2019;Teixeira et al, 2017), that is, heterogeneous areas. Thus, our field study is somewhat novel, also demonstrating that SAFER algorithm needs to be evaluated carefully before its application in irrigated monoculture areas, since the algorithm underestimated (first 30 DAS) and overestimated (after 30 DAS) ET f and, consequently, ET.…”

Mapeamento espaço-temporal da evapotranspiração na bacia do rio Paracatu utilizando imagens MODIS e o algoritmo SAFER

“…O SAFER (Simple Algorithm For Evapotranspiration Retrieving) é um algoritmo simplificado que tem apresentado bons resultados na estimativa da evapotranspiração (ET) e da biomassa vegetal (Bio) em larga escala (Teixeira et al, 2013a;Andrade et al, 2016). Esse algoritmo tem a vantagem de não ser obrigatória o uso da banda termal e de poder ser aplicado com dados meteorológicos provenientes de diferentes tipos de estações (agrometeorológicas, convencionais e automáticas) sendo essa uma característica importante por possibilitar a avaliação das tendências históricas dos componentes do balanço de energia e da produtividade da água em larga escala ao longo dos anos, haja vista que sensores automáticos são avanços relativamente recentes na tecnologia instrumental (Teixeira et al, 2013b).…”

Uso do algoritmo SAFER na análise espaço-temporal da evapotranspiração em áreas de produção agropecuária do município de Maracaju, MS / Spatio-temporal analysis of evapotranspiration in agricultural production areas in the municipality of Maracaju, Brazil, using algorithm SAFER

“…Nesse caso, são utilizados dados de sensoriamento remoto juntamente com modelos e/ou algoritmos (Warren et. al., 2013;Lima et al, 2014;Andrade et al, 2016;Teixeira et al, 2020).…”