Great Western Woodlands Diameter, Height, Basal Area, Sapwood Area and Aboveground Woody Biomass Data 

This data contains stem diameter, height measurement, basal area, sapwood area and above ground living biomass calculations for all for stems ≥10cm diameter at breast height in four 1 ha plots at the Great Western Woodlands site in Western Australia from 2012 - present. 

We at TERN acknowledge the Traditional Owners and Custodians throughout Australia, New Zealand and all nations. We honour their profound connections to land, water, biodiversity and culture and pay our respects to their Elders past, present and emerging. This work was funded by the Terrestrial Ecosystem Research Network (TERN), an Australian Government National Collaborative Research Infrastructure Strategy (NCRIS) project. 

This dataset records tree diameter and height data used to calculate above-ground biomass across vegetation types in Australia. This data is important for mapping and monitoring changes in plant growth, carbon storage and terrestrial energy fluxes. 

Tree survey:
All trees >10 cm diameter at breast height in four 1 ha plots within the Great Western Woodlands site were mapped in 2012. Stem diameter was measured at breast height (1.3 m) with measuring tape. Tree height was measured using Nikon Forestry 550 hypsometer.
Biomass, basal area and sapwood calculation:
Standing above ground biomass (kg) was calculated using allometric regressions published in: Jonson J. H., Freudenberger D. (2011) Restore and sequester: estimating biomass in native Australian woodland ecosystems for their carbon-funded restoration. Australian Journal of Botany 59, 640-653. Basal area (m2) for each tree was calculated as: pi/4*DBH^2. Sapwood area (m2) for each tree was calculated as: 0.42*exp(-0.003*10*DBH)*basal area. Biomass of dead stems was calculated using a reduction factor of 85% of alive biomass (Bennett et al., 2013) Note: both alive and dead stems are included in the site level calculation of above ground woody biomass.