A data set consisting of seventeen functional traits collected on 43 saplings from a Control and 33 saplings from a long-term drought experiment site in a tropical rainforest in NE Amazonia, Brazil. The experiment was designed to exclude 50% of the incoming rainfall to the soil and was conducted over a 1ha area, alongside the experiment there is a control (non- drought plot) of a corresponding size. The samples were collected in 2017, fifteen years after the start of the experiment on trees with a diameter at breast height (1.3m) of 1-10cm. The purpose of the dataset was to assess if traits relating to plant metabolism (photosynthesis and respiration) and plant hydraulic processes had been significantly altered in trees growing under drought conditions. Full details about this dataset can be found at https://doi.org/10.5285/ca147ac9-ac68-4348-b5f0-dcd483ef3a85

Data comprise tree trait data collected during September and October 2016 (the peak dry season), in the Caxiuanã National Forest Reserve, eastern Amazon, Brazil. 17 traits (including plot type, tree species name, diameter at breast height, tree light score, carboxylation capacity, electron transport capacity, leaf respiration in the dark, stomatal conductance, stem CO2 efflux, leaf mass per area, leaf nitrogen and phosphorus content, branch wood density, leaf water potential, xylem pressure, lumen conductance, percentage loss of conductivity, hydraulic Safety Margin and leaf area to sapwood area ratio) of 176 trees (most common genera) were sampled across two experimental plots: a one-hectare through-fall exclusion plot with a plastic panel structure that excludes 50% of the canopy through-fall and has done since 2002 and a corresponding one-hectare control plot without any drought structure. This data comes from the Caxiuanã through-fall exclusion (TFE) experiment located in the terra firma forest, on yellow oxisol soils at 15 m above sea level, with a mean annual rainfall between 2,000–2,500 mm and a pronounced dry season between June and November. Full details about this dataset can be found at https://doi.org/10.5285/441565b3-0a7d-4d3c-a7a8-7d7b487c1462