Uso de índices espectrais para avaliação da estimativa de absorção de CO2 pela vegetação para o município de Uberlândia - MG: 2006 - 2020

Abstract

The absorption of carbon dioxide (CO2) by vegetation can be estimated by the methodology proposed by Rahman et al. (2000) called CO2flux, considering the spectral indices obtained through data from remote sensors. This methodology is usually used in the estimates made for regions of tropical and temperate forests, although there are already studies using it in other regions, such as the Cerrado. For the present work, this methodology was applied to the entire municipality of Uberlândia-MG, over a time series between the months of April to October of 2006 and 2020. The values of CO2flux obtained were correlated with the meteorological variables of temperature, precipitation, relative humidity and solar radiation, in addition to data on change in land use and cover in the municipality. Through the analysis it was possible to identify higher values of carbon absorption for the month of April compared to the other months considered in this study. In addition, the correlations indicated a greater relationship between the values of the index and the variables of mean relative humidity (R = 0,50), mean relative humidity of 30 days (R = 0,84) and accumulated precipitation of 30 days. (R = 0,70). When correlated with land use data by agriculture and pasture, CO2flux values obtained a correlation of 0.72 and -0.76 respectively, indicating a strong positive influence of agriculture and strong negative influence of pasture on the index values.