Hemispherical photography has been collected across Australia to characterise plant canopy cover and structure, and to study leaf area index. Hemispherical photography is a technique for quantifying plant canopies via photographs captured through a digital camera with hemispherical or fisheye lens. Such photographs can be captured from beneath the canopy, looking upwards, (orientated towards zenith) or above the canopy looking downwards. These measurements have typically been collected in conjunction with the Statewide Landcover and Trees Study (SLATS) star transects field data together with plant canopy analysers such as LAI-2200 and CI-110.
Data can be downloaded from https://field.jrsrp.com/ by selecting the combination Field and Hemispheric imagery. Photographs can be accesed through the right-hand side panel, or by finding the file_loc attribute in the csv file.
The following organisations contributed to the data collection: Joint Remote Sensing Research Project, Royal Melbourne Institute of Technology, Curtin University, University of Adelaide and CSIRO.
This work was jointly funded by the Terrestrial Ecosystem Research Network (TERN), an Australian Government National Collaborative Research Infrastructure Strategy (NCRIS) project.
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.
Hemispherical photography provides a number of structural measurements that can be used for calibration and validation of LiDAR derived products, such as LiDAR derived fractional cover and leaf area index.
Sampling Strategy - A sample of images (5, 7 or 13 depending on site) are collected in a star or cross formation around a central point. All images are referenced to the central geographic location. The naming convention of the imagery enables positioning of each individual image in relation to that central point (see hemispherical_photography_filenaming_convention.txt in the data links). Three images are collected at each sampling point, using different exposures. Samples are collected at dawn, dusk or in overcast conditions.