Today's data for tomorrow's future: Partnerships add value to the Cathedral Peak long-term observation platform
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SAEON's Grassland Forest Wetland Node is very fortunate to have the involvement of Prof. Trevor Hill and Dr Jemma Finch, both from the Palaeoecological Lab in the School of Agricultural, Earth and Environmental Sciences (SAEES) at the University of KwaZulu-Natal, in the Cathedral Peak Research Catchments and surrounds.
Their work provides vital pieces in the puzzle of determining long-term patterns and potential shifts related to human-induced climate change. As part of a trans-discipline effort, their work provides context and helps to benchmark the more recent investigations into pattern and processes within a deep time context.
Students interested in palaeoecology can contact us for more information if they are interested in pursuing this fascinating adventure into the world of the past that will help us understand the meaning of today's data for tomorrow's future.
Read more about this this valuable partnership at Cathedral Peak:
A long-term perspective on environmental change at Cathedral Peak
By Dr Jemma Finch
To fully understand any environment, it is important to consider pre-historic and historical factors and processes. Environments and climates are not static, but dynamic over time, a subject which has become more topical with the rise in prominence of human-induced climate change.
In the Drakensberg Mountains, a long-term perspective is necessary to address ecological questions such as:
- Are refugial forest patches a natural feature of the landscape or were these once more widespread?
- How did early human occupants and more recent colonial farmers impact the landscape?
- How do current fire management practices compare with natural fire regimes prior to human influence of the landscape?
- Have invasive species such as bracken fern always played a dominant role in the landscape?
- How do such species respond to changes in fire regime?
Such questions have important management ramifications and can help to inform conservation practices in the Ukhahlamba Drakensberg Park.
In the absence of an actual 'time-machine', palaeoecological tools can be used to provide unique insights into past environmental dynamics, forming an important, yet underutilised, avenue for assessing landscape change over decadal, centennial and millennial timescales.
A record of change over time
Natural archives such as lake and wetland sediments, among others, can preserve detailed microfossil assemblages and geochemical signatures, essentially providing a record of change over time. Researchers extract undisturbed sediment cores from these systems and conduct detailed analyses back in a controlled laboratory environment.
At each depth, an array of analyses are used to provide evidence of environmental conditions, e.g. charcoal fragments are an indicator or proxy for past fire events/regimes. Microbotanical remains, such as fossilised pollen grains, have unique sculpturing that is used to identify the parent plant group, and hence gain an understanding of changing vegetation community composition.
Together, the range of available techniques can be used to build a picture of changing vegetation, fire regimes, herbivory, and general climatic changes over time. When the analysis is repeated along the length of the sediment core, it becomes possible to piece together a record of change over time. Radiocarbon dating is combined with other specialised techniques to build a timeline for the record.
Postgraduate students
Several postgraduate students at the Palaeoecological Lab in SAEES are currently engaged in palaeo research under the joint supervision of Prof. Trevor Hill and Dr Jemma Finch. A number of these research projects are focused on environmental change in the Cathedral Peak area of the KwaZulu-Natal Drakensberg.
Jared Lodder completed his MSc research project on fossil pollen analysis of a 15,000-year-old sediment core from the Cathedral Peak Catchment VI wetland, reconstructing a long-term record of vegetation and climatic change over the Holocene period. This work was funded by the NRF African Origins Platform and the Palaeontological Scientific Trust, and was recently submitted for publication. Jared is now pursuing a PhD at the University of North West.
As the subject of her MSc research, Tristan Duthie is modelling pollen production and dispersal in the Cathedral Peak landscape, to provide a calibration dataset for palaeo-reconstruction. This work is being conducted in collaboration with Dr Jane Bunting at the University of Hull (UK), and to this end Tristan attended a PolLandCal Workshop in Hull in August 2013. Her project is registered with the SAEON Grassland Forest Wetland Node.
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Luke Bodmann, also registered with SAEON, has extracted a series of sediment cores from three high-altitude wetlands in the Cathedral Peak area to reconstruct high-resolution records of environmental change for the past 1000-2000 years. Luke's MSc research is funded by the ACCESS (Applied Centre for Climate and Earth Systems Science) programme and is co-supervised by Dr Michelle Warburton at SAEES.
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Jessica van der Merwe is investigating past fire regimes using macrocharcoal preserved in Cathedral Peak sediment cores as the subject of her Honours research. Such research will provide long-term insight into past environmental change in this important conservation area and UNESCO World Heritage Site.
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