RESUMEN

In recent years, Brazil has become a major global contributor to the occurrence of national fires and greenhouse gas emissions. Therefore, this study aimed to evaluate the fire foci data of the past 20 years to determine their relationship with climatic variables in various Brazilian regions. The variables evaluated included fire foci, land surface temperature, rainfall, and standardized precipitation index, which were obtained via remote sensing from 2000 to 2019. The data were subjected to trend analyses (Mann-Kendall and Pettitt tests) and a multivariate analysis of canonical variables for evaluation. The results showed that the Midwest and North regions had the highest occurrence of fire foci throughout the study period, and that the North region had the highest accumulated annual rainfall. Thus, these regions require specific public policies to prevent future fires. Overall, the Midwest, Southeast, and South regions exhibit significant increasing fire foci tendencies. Our results reveal that this trend is related to the El Niño-Southern Oscillation (ENSO) phenomena, which alter climatic variables such as precipitation, land surface temperature, and the standardized precipitation index. Finally, the sugarcane growing area had a significant linear relationship with fire foci in the Southeast region, especially in the state of São Paulo, the major national sugarcane producer.

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RESUMEN

Brazil is one of the world's biggest emitters of greenhouse gases (GHGs). Fire foci across the country contributes to these emissions and compromises emission reduction targets pledged by Brazil under the Paris Agreement. In this paper, we quantify fire foci, burned areas, and carbon emissions in all Brazilian biomes (i.e., Amazon, Cerrado, Caatinga, Atlantic Forest, Pantanal and Pampa). We analyzed these variables using cluster analysis and non-parametric statistics to predict carbon and CO2 emissions for the next decade. Our results showed no increase in the number of fire foci and carbon emissions for the evaluated time series, whereby the highest emissions occur and will persist in the Amazon and Cerrado biomes. The Atlantic Forest, Pantanal, Caatinga and Pampa biomes had low emissions compared to the Amazon and Cerrado. Based on 2030 projections, the sum of emissions from fire foci in the six Brazilian biomes will exceed 5.7 Gt CO2, compromising the national GHG reduction targets. To reduce GHG emissions, Brazil will need to control deforestation induced by the expansion of the agricultural frontier in the Amazon and Cerrado biomes. This can only be achieved through significant political effort involving the government, entrepreneurs and society as a collective.

RESUMEN

The growing quest for sustainability in agricultural production systems has been pushing researchers to develop new technologies under different soil and climatic conditions. Based on this, and knowing the socioeconomic importance of the bean, the use of biological nitrogen fixation (BNF) is explored. Thus, the quest for quantitative knowledge of BNF at the phenological stages in a new bean line using promising and commercial strains becomes necessary. The objective of this study was to evaluate the strains UFLA 02 100 and CIAT 899 in the different phenological stages of the LEP 02 11 common bean strain using the biological nitrogen fixation. The experiment was conducted in a greenhouse on the Maringá-PR campus of the State University of Maringá. The design was a randomized complete block design in a 6x4 factorial scheme with four replications. The factor A comprised six nitrogen sources: Control, strain UFLA 02 100, strain CIAT 899, Nitrogen 60 kg ha-1, strain UFLA 02 100 + Nitrogen 30 kg ha-1, strain CIAT 899 + Nitrogen 30 kg ha-1 and the B factor is the phenological stages V4, R5, R6 and R8. The analyzed variables were: dry mass of nodules (DMN, grams/plant), dry mass of shoot (DMS, grams/plant), nitrogen content in shoot (NCS, %) and accumulation of nitrogen in shoot (ANS, grams/plant). For the statistical analysis of the data, the means test was used for the variables in the stages. The CIAT 899 strain statistically outperformed UFLA 02 100 for most variables and it was found that nitrogen fertilization negatively affected nodulation

A crescente busca pela sustentabilidade nos sistemas de produção agrícolas vem impulsionando os pesquisadores a desenvolverem novas tecnologias nas diferentes condições edafoclimáticas. Com base nisso, e sabendo da importância socioeconômica do feijoeiro, o uso da fixação biológica de nitrogênio (FBN) é explorada. Assim, a busca do conhecimento quantitativo da FBN nos estádios fenológicos em uma nova linhagem de feijão utilizando estirpes promissoras e comerciais se torna necessário. Destamaneira, o objetivo foi avaliar as estirpes UFLA 02 100 eCIAT 899nos diferentes estádios fenológicos da linhagem de feijão comum LEP 02 11 mediante o uso da fixação biológica de nitrogênio. O experimento foi conduzido em casa de vegetaçãono campus de Maringá-PR da Universidade Estadual de Maringá. O delineamento foi o de blocos ao acaso (DBC) em esquema fatorial 6x4 com quatro repetições. O fator A compreendeu seis fontes de nitrogênio: Testemunha, estirpe UFLA 02 100, estirpe CIAT 899, Nitrogênio 60 kg ha-1, estirpe UFLA 02 100+Nitrogênio 30 kg ha-1, estirpe CIAT 899+Nitrogênio 30 kg ha-1 e o fator B os estádios fenológicos V4, R5, R6 e R8. As variáveis analisadas foram: massa seca de nódulos (MSN, gramas/planta), massa seca da parte aérea (MSPA, gramas/planta), teor de nitrogênio na parte aérea (TNPA, %) e acúmulo de nitrogênio na parte aérea (ANPA, gramas/planta). Para a análise estatística dos dados utilizou-se o teste de médias para as variáveis nos estádios. A estirpe CIAT 899 superou estatisticamente a UFLA 02 100 para a maioria das variáveis e constatou-se que a adubação nitrogenada afetou negativamente a nodulação.

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