Examining the ecology of the Karkloof Forest


Dr Jolene Fisher
School of Animal, Plant and Environmental Sciences, University of the Witwatersrand

Afrotemperate forests (such as Karkloof forest) in South Africa are an understudied system. Much of the forest ecological theory is based on systems from the northern hemisphere and the same theory does not necessarily hold true for our forests (e.g. tree ring growth, gap dynamics, fire being necessary for longevity). With this research I aim to improve our understanding of Afrotemperate forest function and dynamics within multi-use landscapes to aid in their management and conservation. I started this research in 2017, and have done multiple field trips each year since. The Karkloof Conservancy, along with private land owners, have been willing allies to this research. To date, 17 forest inventory plots (permanent plots which can be sampled to investigate forest regeneration and dynamics) have been established in the forest owned by Nick and Tim Hancock (Rockwood), Karkloof Canopy Tours, Gunther Dell, Bushwillow, Shawswood, and Braco. Multiple postgraduate and undergraduate students have assisted me with the field work over the years, and so far three honours students have graduated using the Karkloof data. Currently, one MSc and one PhD student are conducting their research into the forests, with the Karkloof data providing a foundation for their research. This research therefore supports capacity development within the higher education sector. Over 2000 individuals have been tagged, each with its information recorded. Species lists for each individual plot will be sent to landowners once the data has been cleaned.
In addition to the research into the ecology of the forest, I have also acquired 3D laser scanning imagery of Karkloof Forest. Laser scanning collects a 3D point cloud of both the elevation and tree structure, at high resolution (25 cm). Using the data from the forest inventory plots, we are able to calculate biomass and ultimately carbon. We then use the field data to create a model in order to map carbon across the entire forest. We are still in the process of collecting data across the entire forest region before we can model carbon. An image of the canopy height across the entire forest is shown below.