Balanço do dióxido de carbono pela emissão em duas situações de transporte madeireiro na Amazônia : unimodal e intermodal

Abstract

Wood products can be considered a carbon reservoir, as trees assimilate this component to its matter during growth process. Especially when they are attributed to uses that last for years, as sawn wood products. However, until these are delivered to their consumer markets, historically there is a large consumption of energy by burning fossil fuels and emission of polluting gases to the atmosphere, due to the long distances traveled. Transport is characterized by a single or more than one modality: highways, waterways, seas, railways, pipelines or air. Consequently, it must be considered that the net carbon stock is minimized by the emission of this activities. This problem guided the present work, with the objective of analyzing the balance of carbon dioxide emission of forest transport in different modes and the sequestration in transported logs. This work was divided into two articles. In Article I the scenario evaluated was the emissions by log transport of a Low-Impact Logging in Rondonia state, through highways and waterways in Brazilian territory and maritime modal to the foreign market. In Article II it was evaluated the emissions of the log transport, entirely through roads of the timber from a Low-Impact Logging in Mato Grosso state to the customer brazilian cities. To calculate the carbon fixation and log stocking the dry mass was calculated, that is equivalent to biomass. Then, carbon and carbon dioxide medium contents was estimated for amazon timber, as described in some literatures. Therefore it was found the total carbon dioxide in the transported cargo between forest management area and sawmills, and until the consumer markets. Equations were used to calculate emissions from transport, using each emission factor equivalent to the modal, the distance traveled and the weight of the cargo. In article I, the road modal, with emission of 4,665.26 tCO2 thoughout the 7,086.1 km transport maximum distance traveled , was more polluting than waterway and maritime, that emitted 2,715.94 tCO2 thoughout 41,304 km, together. The proporton of CO2 emissions to the total stock of transported logs was 19.80%. In article II, 2,211.35 tCO2 were emitted in 39,516.8 km between the forest management area and the sawmill, and the seven Brazilian cities that received the sawn wood. In this way, the emission by trucks is equivalent to 15.46% of the CO2 stock in the wood. It is concluded that for the two analyzed scenarios, transport, in general, did not reduce the entire net stock of carbon present in the trees, thus the carbon balance is positive, and road modal is considerably more polluting than the flow by river and sea.