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1.
An Acad Bras Cienc ; 95(4): e20200656, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38088704

RESUMO

This study estimated biomass and carbon from components, future carbon values ​​and to obtain economic productive value of carbon fixation of a Seasonal Semideciduous Forest. Biomass and carbon were estimated using adjusted equations and selected using regression statistics. The prognosis of the diametric distribution was performed using the movement ratio method. In the economic evaluation, it was estimated productive value of the stand, referring to the current and future carbon fixation capacity. The coefficients of determination (adjusted R²) of the equations ranged from 0.11 to 0.90 and the standard error of the estimate (Syx) ranged from 41.53% to 141.89% for the biomass of the components, and from 0.03 to 0.87 for adjusted R² and from 46.20% to 143.64% for the error, for stored carbon in the components. The total biomass of the tree component estimated was 56.25 t ha-1 and 25.88 t ha-1 of total carbon. Using the future distributions by the method of the ratio of movements, total stored carbon (aerial + roots) estimated was 14.44 t. ha-1 over the 20-year period. The productive value for the fragment reached R$ 299.95 per ha. year-1.


Assuntos
Carbono , Florestas , Biomassa , Carbono/análise , Brasil , Estações do Ano , Árvores
2.
An Acad Bras Cienc ; 92(3): e20200263, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33175016

RESUMO

The main purpose of this paper was to present the Forestry Routing Optimization Model (FRoM) as a version of the classical Vehicle Routing Problem (VRP). This work approaches for wood logistic problems consisting of simple displacement and multiple displacements of trucks toward the stands. The FRoM encompasses both steps into one single integer mixed linear programming model, considering cranes and trucks schedule, fleet reduction, reduction of overtime, reduction of half-load transportation, and approaching the minimum distance traveled along a fixed planning horizon. Some technique constraints were implemented to provide accurate model function. An executed real problem data was used to compare the outcomes. The objective was to carry and transport 21,881.82 tons of lumber from 10 stands using a total of 48 trucks and 5 cranes in a planning horizon of 6 days, which each day has 20 hours of effective work. The FRoM has performed a fleet reduction of 72.92%, eliminating overtime. It has reduced the half-load trips to the order of 3.17% of all routes. The crane's analysis allowed catching points of inefficiency due to operational idleness. The FRoM provided savings of 49.12% at all logistic costs. FRoM has shown to be a good option as a route optimizer for forestry logistics.


Assuntos
Agricultura Florestal , Madeira , Meios de Transporte
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