ABSTRACT With the growing interest in estimating carbon stocks in forests, available allometric e... more ABSTRACT With the growing interest in estimating carbon stocks in forests, available allometric equations have been compiled. These compilations often reveal contrasting models for the same species and site. Rather than choosing a model with the risk of not selecting the best available one, Bayesian model averaging (BMA) offers a way to combine different allometric equations into a single predictive model. In the deterministic version of BMA, existing models with known coefficients are combined. In the statistical version, competing models are at the same time fitted and combined. Using the BMA of deterministic models, we combined three existing multispecies pan-tropical biomass equations for tropical moist forests. The resulting model brought a relatively minor although consistent improvement of the predictions of the aboveground dry biomass of trees. These three models were particular cases of a family of models that were subsequently combined using the BMA of statistical models. Again, the resulting model was able to capture features in the biomass response to diameter that no single model was able to fit. BMA thus is an alternative to model selection that allows integrating the biomass response from different models.
Modelling forest systems. Workshop on the interface between reality, modelling and the parameter estimation processes, Sesimbra, Portugal, 2-5 June 2002, 2003
In response to the growing interest in estimating carbon stocks in forests, available allometric ... more In response to the growing interest in estimating carbon stocks in forests, available allometric equations have been compiled for sub-Saharan Africa. Tree, sprout and stand volume and biomass equations were reviewed. The 850 equations and 125 related references were incorporated into an open-access database on the Carboafrica website (http://www.carboafrica.net). The collected information provides a basic tool for the estimation of biomass and carbon stocks and other purposes, such as bioenergy and fodder supply assessment. A Tier-method approach was developed to illustrate the possible use of the equations. Current available biomass expansion factors that are used to convert a volume to the total aboveground biomass appear to be limited; incomplete species-specific allometric equations are preferred to generalised equations. The analysis of the database highlighted important gaps in available tools to assess forest carbon stocks and changes in these stocks. A quality control assess...
Abstract: The problems caused by the irregular tree shape (longitudinal form or irregularity cros... more Abstract: The problems caused by the irregular tree shape (longitudinal form or irregularity cross-section) are well known for the industrials users (sawmills, veneering industries...): low yield, problems in the drying process due to the occurrence of reaction wood. This paper ...
... Tectona grandis L. (Verbenaceae) with big simple leaves was studied near Malang (088100 S, 11... more ... Tectona grandis L. (Verbenaceae) with big simple leaves was studied near Malang (088100 S, 1128200 E), situated in the eastern part of Java Island, Indonesia. ... Numerical photographs were taken, with a Nikon Coolpix 4500 digital camera, for all the selected leaves. ...
ABSTRACT With the growing interest in estimating carbon stocks in forests, available allometric e... more ABSTRACT With the growing interest in estimating carbon stocks in forests, available allometric equations have been compiled. These compilations often reveal contrasting models for the same species and site. Rather than choosing a model with the risk of not selecting the best available one, Bayesian model averaging (BMA) offers a way to combine different allometric equations into a single predictive model. In the deterministic version of BMA, existing models with known coefficients are combined. In the statistical version, competing models are at the same time fitted and combined. Using the BMA of deterministic models, we combined three existing multispecies pan-tropical biomass equations for tropical moist forests. The resulting model brought a relatively minor although consistent improvement of the predictions of the aboveground dry biomass of trees. These three models were particular cases of a family of models that were subsequently combined using the BMA of statistical models. Again, the resulting model was able to capture features in the biomass response to diameter that no single model was able to fit. BMA thus is an alternative to model selection that allows integrating the biomass response from different models.
Modelling forest systems. Workshop on the interface between reality, modelling and the parameter estimation processes, Sesimbra, Portugal, 2-5 June 2002, 2003
In response to the growing interest in estimating carbon stocks in forests, available allometric ... more In response to the growing interest in estimating carbon stocks in forests, available allometric equations have been compiled for sub-Saharan Africa. Tree, sprout and stand volume and biomass equations were reviewed. The 850 equations and 125 related references were incorporated into an open-access database on the Carboafrica website (http://www.carboafrica.net). The collected information provides a basic tool for the estimation of biomass and carbon stocks and other purposes, such as bioenergy and fodder supply assessment. A Tier-method approach was developed to illustrate the possible use of the equations. Current available biomass expansion factors that are used to convert a volume to the total aboveground biomass appear to be limited; incomplete species-specific allometric equations are preferred to generalised equations. The analysis of the database highlighted important gaps in available tools to assess forest carbon stocks and changes in these stocks. A quality control assess...
Abstract: The problems caused by the irregular tree shape (longitudinal form or irregularity cros... more Abstract: The problems caused by the irregular tree shape (longitudinal form or irregularity cross-section) are well known for the industrials users (sawmills, veneering industries...): low yield, problems in the drying process due to the occurrence of reaction wood. This paper ...
... Tectona grandis L. (Verbenaceae) with big simple leaves was studied near Malang (088100 S, 11... more ... Tectona grandis L. (Verbenaceae) with big simple leaves was studied near Malang (088100 S, 1128200 E), situated in the eastern part of Java Island, Indonesia. ... Numerical photographs were taken, with a Nikon Coolpix 4500 digital camera, for all the selected leaves. ...
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Papers by L. Saint-andré