Panama leaf water potential census 2015-2019

Author(s): Medina-Vega J; Wolfe B

Dataset Information


Site Name: Parque Natural Metropolitano; Bosque Protector San Lorenzo (Fort Sherman)

Variables: Leaf water potential

Date Range: Dec. 1, 2015 - July 9, 2019

Description: This dataset contains values of leaf water potential from a monthly census of predawn and midday measurements conducted on nine trees in each of two sites in Panama from December 2015 to July 2019. The dataset includes individual measurements that were made with a pressure chamber. The measurements were made on the focal trees to complement concurrent measurements of sap flow. The trees were also intensively measured for leaf-level physiological condition during the 2016 ENSO campaign conducted by NGEE-tropics. A subset of measurements was made on leaves that were sealed in plastic bags and protected from solar radiation before they were collected, such that the measurements assessed branch water potential. The dataset contains a csv file that has columns for the time, location, and value of each measurement. The dataset also contains a metadata file, column description file, and an E-Field log file in the recommended NGEE-Tropic formats.


Methods Description: Leaves were collected from the upper canopies of the target trees by cutting the petiole near the branch junction with a razor. Immediately, the leaves were sealed in plastic bags and placed in a cooler with ice. Within 3 hours, generally much less time, the leaves were measured for water potential with a Scholander-type pressure chamber (PMS Instruments, Corvallis, OR, USA). Timepoints of collection were predawn (5:00-6:30 h) and midday (11:30-13:00 h). At each timepoint, three leaves were collected from each tree that was measured. During some censuses, branch water potential was measured by sealing leaves in plastic bags while they were attached to the tree to stop transpiration and covering them with reflective foam insulation to prevent overheating. This was done an hour before predawn measurements for both predawn and and midday timepoints. The rest of the protocol for measuring branch water potential followed that of leaf water potential.

Access Level: Public

Originating Institution(s): Smithsonian Tropical Research Institute

Sponsor Organization(s): Next Generation Ecosystem Experiments-Tropics and by the US Department of Energy, Office of Science, Office of Biological and Environmental Research.

Contact: Wolfe, Brett - Louisiana State University (

Data Download

Version: 1.0

Dataset Citation: Medina-Vega J; Wolfe B (2023): Panama leaf water potential census 2015-2019. 1.0. NGEE Tropics Data Collection. (dataset).

Acknowledgement: Funding for NGEE-Tropics data resources was provided by the U.S. Department of Energy Office of Science, Office of Biological and Environmental Research.

Data Link: Download Dataset

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Wolfe BT, Detto M, Zhang Y-J, Anderson-Teixeira KJ, Brodribb T, Collins AD, Crawford C, Dickman LT, Ely KS, Francisco J, Gurry PD, Hancock H, King CT, Majekobaje AR, Mallett CJ, McDowell NG, Mendheim Z, Michaletz ST, Myers DB, Price TJ, Rogers A, Sack L, Serbin SP, Siddiq Z, Willis D, Wu J, Zailaa J, and S. J. Wright 2023. Leaves as bottlenecks: The contribution of tree leaves to hydraulic resistance within the soil−plant−atmosphere continuum. Plant, Cell & Environment 46:736-746. doi: 10.1111/pce.14524

Medina-Vega JA, Wright SJ, Bongers F, Schnitzer SA, Sterck FJ. 2022. Data from: Vegetative phenologies of lianas and trees in two Neotropical forests with contrasting rainfall regimes. Zenodo. doi:10.5281/zenodo.6403252