From Plant Press, Vol. 24, No. 1, January 2021.
Adapted from an article written by Leonie Bolleurs, University of the Free State, South Africa.
In their search to learn more about the impact of humans and climate change on grasses in the Drakensberg Mountain Centre (DMC), one of the most studied mountain systems in the region, a group of scientists found a new grass species, which they named Festuca drakensbergensis Sylvester, Soreng & M.Sylvester [PhytoKeys 162: 50–54, f. 1, 2. 2020] (common name unknown; herein could be designated the ‘Drakensberg Alpine Fescue’). The Maloti-Drakensberg Park World Heritage Site is a transnational property spanning the border between the Kingdom of Lesotho and the Republic of South Africa.
The team who is working on the project includes Vincent R. Clark, Head of the Afromontane Research Unit at the University of the Free State (UFS), Steven P. Sylvester from the Nanjing Forestry University in Nanjing, Jiangsu, China, and Robert J. Soreng from the Department of Botany at the Smithsonian Institution in Washington, DC., along with Mitsy Sylvester and Caroline Mashau (Ph.D. student).
The species, discovered in February and March 2020, was found during extensive fieldwork by the Sylvesters and Soreng and herbarium research across the 40,000 km2 Maloti-Drakensberg area. The DMC has a very high endemic plant diversity, says Clark (fieldwork vouchers at NU, PRE, US, and more to be distributed).
“It is the only mountain system in [continental] Africa south of Mt. Kilimanjaro with an alpine component,” Clark adds. The DMC has a montane sub-center (below 2800 m) and an alpine sub-center (2800 to 3482 m).
Sylvester says the species was easily recognizable during their fieldwork being found fairly common throughout the Afro-alpine landscape. Although at that point they only knew it to be a distinct taxon, they realized that the species was new to science when they tried to identify it and compared it with other closely related Festuca taxa.
Besides this discovery, the team also reinstated two varieties of Festuca caprina and rediscovered the overlooked F. exaristata E.B.Alexeev, all of them endemic to the DMC. Sylvester believes that these discoveries highlight the importance of these high-elevation ecosystems as harbors of unique biodiversity that require focused conservation efforts.
Although grasses are a dominant species that control the ecosystem function in the Afro-alpine grasslands, they are the least known of all plant species found in these ecosystems. Up until now there has been a lack of focused research on Afro-alpine grasses in southern Africa.
“We provide a taxonomic reappraisal of the Festuca caprina Nees complex that will aid future ecological and biogeographical research in the DMC and allow us to better understand the complexities of these ecosystems and how to conserve and manage them,” says Sylvester.
According to Clark, the new species contributes to the grazing and rangeland value of the Maloti-Drakensberg. “It also has functional value in terms of maintaining ecosystem integrity and associated water production landscape value in the area,” he says.
“The species seems fairly robust to pressures from grazing and burning, being found in both heavily grazed areas and semi-pristine areas, and may prove a useful species as part of a seed mix of native grasses for reseeding degraded Afro-alpine slopes and ski slopes,” mentions Sylvester regarding the benefits of this indigenous species to the region.
The species is very common in Lesotho in Bokong Nature Reserve, Sehlabathebe National Park, and Sani Pass, and at Tiffindell and AfriSki ski resorts. Soreng believes the species is likely to have a wider distribution range across the Maloti-Drakensberg than what was documented at PRE (The National Herbarium, SANBI, Pretoria) before research was cut short due to the COVID-19 pandemic.
According to Sylvester, this taxonomic research feeds into a large-scale ecological study looking at the response of Afro-alpine ecosystems to different grazing and burning regimes that is being run in collaboration with Clark and Soreng, and M. Sylvester and C. Mashau.
“While our research has uncovered interesting novelties and provided a greater understanding of the taxonomy of grasses from high elevation Maloti-Drakensberg, there is still much to be done with regards to taxonomic research of cool-season grasses in southern Africa,” says Sylvester.
Clark supports this notion and states that there is a major need for a better holistic understanding of the alpine zone in the Maloti-Drakensberg, given immediate pressures from over-grazing, land-use transformation, invasive species, and climate change.
“This is because the Maloti-Drakensberg is the most important water tower in southern Africa, providing water for some 30 million people in three countries. As the Maloti-Drakensberg is dominated by natural grasslands, understanding grass diversity and ecological behavior is a primary need in the face of immediate human impacts and global change,” he says.
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