A IDADE DAS PLANTA\u106 5ES DE EUCALYPTUS sp. INFLUENCIANDO OS ESTOQUES DE CARBONO

Abstract

The tree growth and biomass accumulation, as well as the maintenance of forest residue at the soil surface can act in the removal of carbon from the atmosphere through the cycling process of plant material. The objective was to study the influence of Eucalyptus sp. Plantations with 20, 44 and 240 months of age on the variation of carbon in soil and biomass. The carbon in the soil depth was determined by CHNS auto-analyzer and carbon in the vegetation was determined by the biomass in each forest, considering a factor of 0.45 of the dry mass. We determined the density and particle size distribution of soil. For the comparison between plantations, there was analysis of variance and comparison of means of carbon in vegetation and soil, considering the 5 % level of probability. The carbon content and stock in the soil were low, indicating that a natural feature of the category of Paleuldt, or the growth of eucalyptus forests, replacing the field native vegetation did not aggregate a significant increase in the carbon. Although, there was a significant increase carbon in aboveground biomass. It includes forest biomass and litter. So, despite the values of carbon stocks are low, it identified a greater average total in the soil compared to the stock aboveground. Furthermore, this increase aboveground (tree and litter compartments) can be considered significant between the eucalyptus plantations of different ages.O crescimento das \ue1rvores e ac\ufamulo de biomassa, bem como a manuten\ue7\ue3o do res\uedduo florestal na superf\uedcie do solo pode atuar na retirada de carbono da atmosfera gra\ue7as ao processo de ciclagem de material vegetal. O objetivo foi estudar a influ\ueancia das planta\ue7\uf5es de Eucalyptus SP. com 20, 44 e 240 meses de idade sobre a varia\ue7\ue3o de carbono no solo e na biomassa. O carbono no solo foi determinado em profundidade por meio de autoanalisador CHNS e o carbono na vegeta\ue7\ue3o foi determinado pela biomassa em cada floresta, considerando um fator de 0,45 da massa seca. Determinaram-se a densidade e a an\ue1lise granulom\ue9trica do solo. Para a compara\ue7\ue3o entre planta\ue7\uf5es, realizou-se a an\ue1lise de vari\ue2ncia e compara\ue7\ue3o de m\ue9dias do carbono na vegeta\ue7\ue3o e no solo, considerando o n\uedvel de 5 % de probabilidade. O teor e estoque de carbono no solo foram baixos, indicando ser uma caracter\uedstica natural da categoria dos Argissolos ou que o crescimento das florestas de eucalipto em substitui\ue7\ue3o \ue0 vegeta\ue7\ue3o campo nativo n\ue3o agregou um aumento significativo no carbono, apesar de ter ocorrido um aumento significativo de carbono na biomassa acima do solo, a qual inclui a biomassa florestal a\ue9rea e a serapilheira. Portanto, apesar dos baixos valores de estoque de carbono, identificou-se um maior estoque m\ue9dio total no solo quando comparado ao estoque acima do solo. Al\ue9m disso, esse aumento acima do solo (compartimentos arb\uf3reos e serapilheira) pode ser considerado significativo entre as planta\ue7\uf5es de eucalipto com diferentes idades