Allometric relationships and community biomass estimates for some dominant eucalypts in Central Queensland woodlands

Abstract

Allometric equations are presented relating stem circumference to branch, leaf, trunk, bark, total above-ground and lignotuber biomass for Eucalyptus crebra F.Muell. (woodland trees), E. melanophloia Sol. Ex Gaerth. (both woodland and regrowth community trees) and E. populnea F.Muell. (woodland trees). There were no significant differences (P > 0.05) between the slopes of individual lognormal regression lines plotting stem circumference against total above-ground biomass for E. crebra, E. melanophloia and E. populnea. Root-to-shoot ratios and leaf area indices were also determined for the stands contributing to each regression. The regressions were then applied to measured eucalypt stems in the associated plant community to give estimates of each stand’s component (eucalypt tree fraction only) biomass per hectare. These eucalypt regressions were next applied to measured stems of each species on a total of 33 woodland sites in which these eucalypts individually contributed > 75% of total site basal area. Above-ground biomass/basal area relationships averaged 6.74 0.29 t m–2 basal area for 11 E. crebra sites, 5.11 0.28 t m–2 for 12 E. melanophloia sites and 5.81 0.11 t m–2 for 10 E. populnea sites. The mean relationship for all sites was 5.86 0.18 t m–2 basal area. The allometric relationships presented at both individual tree and stand levels, along with calculated biomass : basal area relationships, enable ready estimates to be made of above-ground biomass (carbon stocks) in woodlands dominated by these eucalypts in Queensland, assuming individual stem circumferences or community basal areas are known. However, to document changes in carbon stocks (e.g. for Greenhouse Gas Inventory or Carbon Offset trading purposes), more attention needs to be placed on monitoring fluxes in the independent variables (predictors) of these allometric equations.

Stand biomass estimation method by canopy coverage for application to remote sensing in an arid area of Western Australia

“…Since the main woody vegetation was open forest and woodland, forest and woodland will be described as simply woodland in following sections for simplicity. Although Taniguchi et al (2002a) reported that the average woodland biomass in this research area was 16 Mg ha À1 , which is quite low, the comparison among the aboveground biomass shown in Table 3, that of O' Grady et al (2000) and that of Burrows et al (2000) revealed that the forest biomasses among arid areas with 211 mm precipitation (this report), semiarid areas with 450 mm precipitation (Burrows et al, 2000) and temporal area with 1200 mm precipitation (O'Grady et al, 2000) did not differ significantly at the same SBA level. The area with good environmental conditions had high biomass comparable to that of the other climatic area.…”

“…In the case of the woodland biomass calculation with allometric equations in E. camaldulensis woodland, the independent variable of the allometric equation E(I) was DBH 2 Â H, but the estimation accuracy of equation E(2) became better than that of equations E(10) or E(11). In other climatic areas of Australia, O'Grady et al (2000) and Burrows et al (2000) adopted SBA as their independent variable for biomass estimation equations, although they named the forest biomass estimation equations as Stand Allometric Equations. Their research areas were the temporal eucalyptus forest with 1200 mm annual precipitation and the semiarid eucalyptus forest with 450 mm annual precipitation.…”

Comparing above-ground biomass among forest types in the Wet Tropics: Small stems and plantation types matter in carbon accounting

“…We used a modified transect method for recording tree locations within a 0.05 ha (50 Â 10 m) plot (Stohlgren et al, 1995;Back et al, 1997;Back et al, 1999;Burrows et al, 2000;Burrows et al, 2002;Crowley et al, 2009), that ensures both accuracy and repeatability, and is suited to estimating high stem densities in rainforest patches on steep slopes. Sampling was conducted about the central line (x-axis) of each plot, which was oriented along a compass bearing (Fig.…”

Allometric models for estimation of aboveground carbon stocks in improved fallows in eastern Zambia

“…However, previous studies show that generalized models do not accurately predict aboveground biomass (Maraseni et al 2005;Litton et al 2006;Litton and Kauffman 2008). Major sources of uncertainties include (i) differences in site indices, including soil and climatic conditions, unquantified diameter and height ranges (Specht and West 2003), narrow ranges of diameter and height (Burrows et al 2000), and (iv) differences in age classes and tree density (Chen et al 1998;Lin et al 2001). Generalized models based on pooled data from different sites can be used to estimate C stocks of species at different sites as long as trees are of the same age and are sharing the same diameter and H ranges, and are growing in a location with similar site indices.…”