Allometric Models for Estimating Aboveground Biomass in Short Rotation Crops of Acacia Species in Two Different Sites in Chile

We evaluated the ability of different allometric models to estimate the biomass production of short-rotation woody crops of Acacia dealbata, A. mearnsii and A. melanoxylon. Models considered the adjustment and validation of biomass functions and biological restrictions, such as the use of additive components of the biomass (stem, branches, and leaves). Adjustments of linear and nonlinear models of the three acacia species—established in two locations and of three densities in southern Chile—were utilized. Systems of equations were adjusted to guarantee the addition of the biomass components and the trees’ total biomass. The selection of models was performed based on their goodness of fit and predictive quality. Methods that accounted for the correlation between biomass components granted an additively consistent equations system with efficient estimates and reliable prediction intervals.

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Production and Regression Models for Biomass and Carbon Captured in Gmelina arborea Roxb. Trees in Short Rotation Coppice Plantations in Costa Rica

Forests ◽

10.3390/f10070593 ◽

2019 ◽

Vol 10 (7) ◽

pp. 593

Author(s):

Carolina Tenorio ◽

Róger Moya ◽

Edgar Ortiz-Malavassi ◽

Dagoberto Arias

Keyword(s):

Costa Rica ◽

Biomass Production ◽

Regression Models ◽

Carbon Capture ◽

Goodness Of Fit ◽

Short Rotation Coppice ◽

Total Biomass ◽

High Fertility ◽

Gmelina Arborea ◽

Short Rotation

Mortality, diameter at 30 cm over ground level, height, biomass production, and carbon capture (CC) for different tree components (trunk, bark, branches, and leaves) in two locations in Costa Rica, during their first three years and with three plantation spacings (1.0 × 0.5 m, 1.0 × 1.0 m, and 1.0 × 2.0 m) were obtained for Gmelina arborea Roxb. trees growing in short rotation coppice systems (SRC). In addition, regression models were developed to predict biomass production and CC using location, age, spacing, and their interactions. Biomass production was measured by weight of trees without considering dendrometric variables. Results showed that mortality was lower than 15% for one location, with probable high fertility, and almost 85% for the other location. Diameter and height of trees increased with plantation age in both locations. The highest biomass production and CC were observed in the spacings of 1.0 × 0.5 m2 and 1.0 × 1.0 m2, with 20 Mg/ha/year and 8 Mg/ha/year, respectively. The models to predict biomass production in trunk with bark, branches, leaves, total biomass without leaves, and CC in trunk, branch, and total biomass were developed using this equation: Y = β1 + β2 (location × age) + β3 (age) + β4 (spacing). The R2 values varied from 0.66 to 0.84, with error from 0.88 to 10.75 and indicators of goodness of fit from 60 to 83%.

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A method of forcing additivity of biomass tables when using nonlinear models

Canadian Journal of Forest Research ◽

10.1139/x85-193 ◽

1985 ◽

Vol 15 (6) ◽

pp. 1184-1187 ◽

Cited By ~ 19

Author(s):

David D. Reed ◽

Edwin J. Green

Keyword(s):

Nonlinear Models ◽

Total Biomass ◽

Allometric Models ◽

Tree Component ◽

Relationship Of ◽

The Relationship

A procedure is presented for estimating the coefficients of allometric models for predicting tree component biomass. The resulting equations force the sum of the component estimates to be equal to the estimate of total biomass. An illustration of the procedure is given using published biomass data and the relationship of this procedure to previously published procedures is discussed.

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Short Rotation Wood Crops in Latin American: A Review on Status and Potential Uses as Biofuel

Energies ◽

10.3390/en12040705 ◽

2019 ◽

Vol 12 (4) ◽

pp. 705 ◽

Cited By ~ 9

Author(s):

Róger Moya ◽

Carolina Tenorio ◽

Gloria Oporto

Keyword(s):

Latin America ◽

Latin American ◽

Total Biomass ◽

Important Species ◽

Climate Conditions ◽

Short Rotation Woody Crops ◽

Short Rotation ◽

Harvesting Systems ◽

Biomass Yields ◽

Latin American Countries

Studies related to biomass production, with a focus on energy uses for short-rotation woody crops (SRWCs), are limited in Latin America. The research that is available relates to a variety of tested SRWC species (50 species), however, the most important species are Populus, Salix, Eucalyptus, Acacia, and Gmelina arborea. In the existing studies, stocking densities varied from 1111 to 20,000 trees per hectare, with square or rectangular spacing. One important advantage of SRWC systems in this region, compared to most regions worldwide, is the predictability of biomass yields due to the tropical climate conditions of the majority of the Latin American countries. Rotations of three and four years can be projected to produce total biomass yields of 30–50 tons/ha, with increments of 10–20 tons/ha/yr. Fertilization is performed in SRWC with the aim of preventing soil degradation and maintaining further production. In regards to possible uses of biofuel generated from SRWC in Latin America, an inconvenience is that there are neither well-established harvesting systems nor conventional pre-treatments to process the biomass. Processes that are available in the region that use biomass from SRWC for energy production are gasification and pellet production. Other potential biofuel processes, such as torrefaction and biochemical conversion, are limited in this area.

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