Daintree Rainforest, Cow Bay Stem Diameter, Height and Aboveground Woody Biomass Data 

This data contains stem diameter, height measurement and above ground living biomass calculations for an Australian tropical rainforest. Diameter and height measurements for stems ≥10cm diameter at breast height were sampled in 2012, 2018 and 2023 within a 1 ha plot within the Daintree Rainforest Cow Bay site. 

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:
The 1 ha plot was divided into 25 subplots (20 x 20 m). All individual stems ≥ 10 cm diameter at breast height (1.3 m) were mapped within each 20 x 20 m subplot to an accuracy of 0.5 m. Each subplot is temporarily divided into 10 x 10 m quadrats to assist in mapping. Heights are recorded to the nearest 1 metre for each measured stem and are recorded as the length of the stem from ground to highest leaf, not height above ground level. Tree height was not measured in 2018 or 2023, with height values from 2012 used in biomass calculations for 2018 and 2023.
Biomass calculation:
Above-ground biomass was calculated for each stem >10 cm diameter at breast height using the allometric equation from Chave et al 2014: Chave, J., Réjou-Méchain, M., Búrquez, A., Chidumayo, E., Colgan, M.S., Delitti, W.B., Duque, A., Eid, T., Fearnside, P.M., Goodman, R.C., Henry, M., Martínez-Yrízar, A., Mugasha, W.A., Muller-Landau, H.C., Mencuccini, M., Nelson, B.W., Ngomanda, A., Nogueira, E.M., Ortiz-Malavassi, E., Pélissier, R., Ploton, P., Ryan, C.M., Saldarriaga, J.G. and Vieilledent, G. (2014), Improved allometric models to estimate the aboveground biomass of tropical trees. Glob Change Biol, 20: 3177-3190. https://doi.org/10.1111/gcb.12629
Wood density values were were taken from a database of species of northern Australia (CSIRO unpublished)