Estimativas de biomassa e carbono em áreas de vegetação secundária no território paraense

Abstract

Land use dynamics is a very intense process in the Amazon landscape because forest areas are constantly targets of deforestation, often illegal, which compromises the environmental balance of this ecosystem. In this context, a widespread element in the region's landscape is secondary vegetation (SV). The SV appears after a disturbance and can evolve and reach the characteristics close to a primary forest. This work aims to generate above-ground biomass and carbon estimates for the SV areas in the State of Pará for 2014. The methodology uses the variable GSDY (Growing-Season Degree-Years), calculated by SV age (TerraClass), temperature, and precipitation. The variable GSDY is part of a model proposed by Johnson et al. (2000) and Zarin et al. (2001), which generates above-ground biomass and carbon estimates. VS was classified into five classes according to its age. More than 6.9 million hectares of VS were mapped in the State of Para, representing more than two billion tons (t) of biomass (one million t of carbon) contained in VS. More than 2.8 million hectares of VS were vulnerable in 2014 because of SEMAS – PA Normative Instruction that enables cleaning these areas five years old or less (except those protected by law), with no environmental authorization needed. The SV loss could represent a considerable carbon emission to the atmosphere and massive damage to this region's balance.