Research Highlights - African Termites
Savannas are dynamic, heterogeneous systems that are ultimately driven by water availability at a range of scales, but they are also strongly influenced by organisms and fire. Scientists are using the CAO to better understand the hydro-geomorphological process that shape these savanna landscapes and vegetation, and to map the influences of fire and herbivory on vegetation structure and biomass in this system.
CAO measurements of termite mound and woody vegetation spatial distribution have been used to quantify hillslope hydrological seepage zones in Kruger's savannas. Termites tend not to build mounds on clay soils, probably due to risk of inundation; this renders termite mounds novel indicators of soil conditions. We have found that spatial pattern of hydrological seepage zones, mapped using termite mounds as a surrogate, can provide a unique window into predicting the effects of changing climate on savanna landscapes. Traditional climate models ignore hillslope-scale processes, but savanna responses to climate change will depend heavily upon the hydro-geomorphological interactions mapped here for the first time.
Hillshade view of savanna hillslopes on granite substrates. The high resolution LiDAR imagery reveals the spatial distribution of termite mounds, which are restricted to the hillslope crests.
Sectional view of the LiDAR returns from the CAO. Termite mounds, terrain and woody vegetation canopy are clearly identifiable in the LiDAR point cloud.
Color-infrared image from the CAO spectrometer. Woody vegetation is depicted in shades of red and dark green. Note how closely the hillslope distribution of woody vegetation follows that of the termite mounds in the top image.