Dinâmica das emissões de metano entérico na pecuária bovina paraense de 2008 a 2023

Livestock production in the Amazon plays an important economic role in the state. According to data from IBGE (Brazilian Institute of Geography and Statistics), in 2022, the state of Pará was the second largest herd in Brazil, behind the state of Mato Grosso with approximately 34.3 million head of cattle. This study sought to estimate the emission of enteric methane gas from livestock in the state of Pará from 2008 to 2023. To calculate the emission, the IPCC (2006) “Tier 2” model was used, dividing the herd into four groups: 0 to 12 months, 13 to 24 months, 25 to 36 months, and > 36 months. The information collected was subjected to statistical tests using RStudio4.4.1 Software, which analyzed the correlation (Kendall's Tau) between animal distribution and total annual emissions. The results showed that livestock farming in Pará has become more efficient in recent years, as it presented a lower standard deviation between age groups. Regarding correlation, the calculations suggest that there is greater agreement between the number of heads of cattle aged 0 to 12 months and > 36 months with the annual emission of CH4, τ index of 0.3 and 0.717, respectively. Regarding the distribution of the herd, the studies concluded that the most efficient distribution is 31% of calves, 27% of sovereigns, 20% of heifers and 22% of adults.