Abstract Forest ecosystems play an important role in mitigating the concentration increase of carbon dioxide (CO2) in the atmosphere through carbon sequestration by plants and its storage in biomass and soil. The objective was to determine the aerial biomass carbon stock in a dry tropical forest in Brazil. It was developed between 2012 to 2015, in an area with an advanced regeneration stage (50 years) in the semi-arid region of Pernambuco and it was used 40 permanent plots (400 m²) distant 80 m apart, with 50 m from the border, totaling 1.6 ha of the area to sample the shrubby-arboreal component, where all individuals with circumference at breast height (1.30 m of the soil) equal or greater than 6 cm were identified, measured and labeled in 2012 and remeasured in 2015. It was calculated the biomass and carbon stocks through developed equations available in the literature. The results showed that the total biomass and carbon stock in the first year was 27.97 e 12.92 Mg.ha-1 while in 2015 it was 18.49 and 8.39 Mg.ha-1 respectively. The results showed a biomass and carbon stock reduction of more than 30% in the period evaluated, even this, the area manages to present values within the expected pattern for the region, assuring the importance of sustainable forest management of these native/natural vegetation areas.

RESUMO Este trabalho teve como objetivo estabelecer uma metodologia de propagação vegetativa via técnica de miniestaquia para Mimosa Caesalpiniifolia. Para tanto, foram conduzidos três experimentos independentes: o primeiro avaliou a sobrevivência e produção das minicepas; o segunda testou a interação entre tipos de miniestacas (apical e intermediária) e diferentes concentrações de ácido indolbutírico (AIB; 0, 2.000, 4.000 e 6.000 mg.L-1) no enraizamento adventício; e o terceira analisou o efeito da redução da área foliar (0%, 25%, 50%, 75% e 100%) nas miniestacas. A sobrevivência das minicepas aos 180 dias foi de 80%, com rendimento médio de 5 brotos por minicepa aos 120 dias. Miniestacas apicais apresentaram maior porcentagem de enraizamento, sem aplicação de AIB, superior a 80%. Por outro lado, a aplicação de AIB promove aumento da porcentagem de enraizamento em miniestacas intermediárias. Os tratamentos sem redução foliar e com redução de 25% promoveram melhores resultados quanto ao enraizamento e desenvolvimento das plantas. Os resultados confirmam a hipótese de que a técnica de miniestaquia é viável para propagação de Mimosa Caesalpiniifolia.

ABSTRACT This study aimed to establish a methodology for vegetative propagation via mini-cuttings technique for Mimosa Caesalpiniifolia. For such, three independent experiments were conducted: the first one evaluated survival and production of mini-stumps; the second tested the interaction between mini-cuttings types (apical and intermediate) and different concentrations of indolbutyric acid (IAB; 0, 2,000, 4,000 and 6,000 mg.L-1) on adventitious rooting; and the third analyzed the effect of leaf area reduction (0%, 25%, 50%, 75%, and 100%) on mini-cuttings. Mini-stumps survival at 180 days was 80%, with an average yield of 5 sprouts per mini-stump at 120 days. Apical mini-cuttings demonstrated a higher rooting percentage, without IBA application, higher than 80%. On the other hand, IBA application promotes increased rooting percentage in intermediate mini-cuttings. Treatments without leaf reduction and with reduction of 25% promoted better results concerning rooting and plant development. Results support the hypothesis that mini-cuttings technique is viable for the propagation of Mimosa Caesalpiniifolia.

RESUMO: Com o aumento nos custos dos combustíveis, é fundamental atuar em medidas que envolvam o planejamento e o controle nas atividades com consumo elevado. Dessa forma, objetivou-se modelar o consumo de combustível da carreta utilizada no transporte rodoviário florestal. Para isso, dados de duração, distância percorrida, velocidade média, consumo de combustível e carga transportada pelos veículos nas operações das viagens carregado, vazio e ciclo total foram coletados nas regiões de Campo do Tenente (planta florestal) a Piên (planta industrial) no estado do Paraná. A correlação linear de Pearson foi utilizada para determinar a relação entre as variáveis, ao passo que o procedimento Stepwise foi empregado para compor as equações de regressão na estimativa do consumo de combustível. As maiores correlações foram observadas entre a distância percorrida, carga líquida e velocidade média com o consumo de combustível; ocorrendo, também, correlações significativas entre a distância percorrida e a velocidade média. As equações ajustadas foram estatisticamente adequadas para estimar o consumo de combustível em função da distância percorrida, da carga líquida transportada, da velocidade média e da duração nas viagens carregado, vazio e ciclo total de transporte rodoviário florestal.

ABSTRACT: As fuel costs increase, it is essential to take measures involving planning and control on any activities with high consumption. Thus, the main aim of this work was modeling the fuel consumption of forest road transportation by truck. We collected data about time, driving distance, average speed, fuel consumption and the load carried by the vehicle for loaded trips, unloaded trips, and the total cycle of forest transport in regions between the municipality of Campo do Tenente (forest site) and Piên (factory) located in Paraná state, Brazil. The Pearson's correlation was used to determine the relationship between variables, while the Stepwise procedure was used to generate regression equations to estimate fuel consumption. The highest correlations were found between fuel consumption and driving distance, average speed and liquid weight of the load; also, there was a significant correlation between driving distance and average speed. Adjusted equations were statistically adequate to estimate fuel consumption based on driving distance, liquid weight of the load, average speed and duration time for loaded trips, unloaded trips and the total forest road transportation cycle.