Material flow analysis and CO2 footprint in lumber from managed Brazilian Amazon rainforests.

• Autor(a) principal: Numazawa, Camila Thiemy Dias
• Data de Publicação: 2018
• Tipo de documento: Tese
• Idioma: eng
• Título da fonte: Biblioteca Digital de Teses e Dissertações da USP
• Texto Completo: http://www.teses.usp.br/teses/disponiveis/3/3146/tde-31012019-073206/
• topic: Absorção; Amazonian forest management Resource efficiency; Dióxido de carbono; Lumber; Madeira; Manejo florestal; Material flow analysis. CO2 footprint

Using wood produced under forest management in the Amazon has been proposed as a way of preserving the ecosystem, generating jobs and to aid in climate change mitigation by using wood products as carbon stock and through CO2 uptake from the atmosphere during forest regrowth. However, the scarcity of research based on primary data of Amazonian lumber incorporated into construction can unknowingly lead to incorrect forest management and consequently forest destruction. Besides, it is necessary to verify the real environmental impacts. Two approaches were applied in this research to evaluate the wood product chain: material flow analysis and CO2 footprint calculation of managed Amazonian lumber. The research quantified the resource efficiency and CO2 footprint based on residue generation during the raw extraction in 5 forest plots in State of Pará, followed by the lumber production and the end-of-life phases, giving the CO2 balance between the emissions from residue decomposition and the CO2 uptake during forest regrowth, disregarding the energy consumption. Results indicated that the large quantities of logging residues are the main source of CO2 emissions in the material flow from selective logging, ranging from 9% to 36% of the initial forest biomass, while timber logs represented between 4% and 11%. Logging residues ranged from 2.9 t t-1 to 3.1 t t-1 per tonne of log. Combined with an average sawmill lumber yield of 54%, wastage rate values increased to between 5.7 t t-1 and 6.6 t t-1, resulting in a CO2 footprint of managed Amazonian lumber ranging between -6.6 tCO2 t-1 for reduced impact logging as carbon stock, to emissions of 6.1 tCO2 t-1 from cradle-to-gate for conventional logging. From cradle-to-grave the total CO2 footprint of lumber is estimated to range from neutral to 7.5 tCO2 t-1. Resource efficiency ranged from 13% to 15%. In this study, only the forest under reduced impact logging was able to fully recover its initial aboveground biomass, showing that in most cases regulations in the New Forest Code for Amazon forest management may not ensure sustainable logging, leading to forest destruction. Policies need to be improved and integrated with results from empirical research based on primary data to achieve sustainable exploitation of the Amazon forest.