Daintree Rainforest, Cape Tribulation Leaf Functional Trait Data, 2010 - 2014 

This dataset contains leaf functional trait measurements describing leaf structure, chemistry and metabolism collected from the Daintree Rainforest, Cape Tribulation site, in the dry season 2012 and wet season 2014. 

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. 

Assessing infraspecific and seasonal variability in leaf traits can help develop our understanding of both vegetation distribution and providing Dynamic Global Vegetation Models with an accurate representation of carbon, water and energy budgets. 

Sampling description
Leaf samples were collected from individual plants at two time points during the dry season 2012 and wet season 2014. While repeated measurements on the same individual plant between the two time points was not always possible, plants were selected to include locally dominant species and to provide a wide range of leaf morphology.
Leaf gas exchange
At each visit, young, fully developed leaves from two sun exposed branches were chosen from each selected tree. Leaf gas exchange measurements were concentrated in the morning. Sun exposed branches were excised and the cut end of the branches immediately placed in a bucket and then recut under water to re-establish the xylem water column. For each leaf, approximately light-saturated (1500 µmol photons m-2 s-1) measures of net photosynthesis were taken at ambient CO2 concentration, 400 µmol mol-1 (ppm) and then at 1500 ppm. The leaf was next wrapped in aluminium foil for 30 minutes before respiration in darkness was measured, still at 400 ppm CO2. Air flow was held constant and a constant chamber block temperature was adopted, set marginally (ca. 1°C) higher than expected morning air temperatures to counter the effect of transpirational cooling and to ensure leaf and ambient air temperatures were similar. Gas exchange measurements were recorded using a portable photosynthesis system (Li-Cor 6400, Li-Cor, Lincoln, NE, USA), using a 6 cm2 chamber fitted with a red-blue light source (Li-Cor 6400-02B LED)
Leaf area and dried mass
On completion of the gas exchange measurements leaves were weighed for fresh mass and scanned for leaf area before being dried in an oven at 70 °C for a minimum of 48 hours, after which their dry mass was recorded.
Leaf chemistry
Oven-dried leaf material was used for determination of total leaf nitrogen and phosphorus: dried ground leaf material was hot-digested in acid-peroxide before colorimetric analysis using a flow injection system.
All leaf trait data are mean values of leaves collected from the same branch.