#01 2023

Baseline for a long-term vegetation study at the Square Kilometre Array/Meerkat National Park

By Kudakwashe Musengi, Helga van der Merwe, Tshililo Ramaswiela and Wynand Calitz, Arid Lands Node

Quiver tree overlooking the Meerkat National Park (Photo: Wikimedia)

NRF-SAEON is establishing an environmental baseline for the National Research Foundation (NRF) properties on which the Square Kilometre Array (SKA) telescope is being developed. In June 2019 the last of the landowners and livestock vacated the farmland. This change in land use is an ideal opportunity to initiate long-term monitoring to assess changes in flora and fauna as land reverts from livestock farming to an environmentally protected area (Meerkat National Park). 

Several responses are being anticipated, which should be quantified in terms of ecosystem re-organisation, for example, diversity, composition and structure. Additionally, the change in ecosystem functioning needs to be expressed in terms of productivity, hydrological functioning and nutrient cycling, and a change in threats such as alien invasive species.

The adjacent farmland is still being used for livestock grazing. It will be important to compare changes on the SKA property with adjacent farmland that contain a similar abiotic environment (such as climate, soils and topography), but which continue to practice the conventional land use of the region – small-stock farming. A study of spatiotemporal change across a large area (135 000 hectares) following the removal of livestock in an understudied arid environment will improve our understanding of the vegetation dynamics and functioning of such dryland systems.

Kuda Musengi (PDP postdoc) laying a 100-metre-long rope marked at one-metre intervals that is used to place the point that is surveyed using the point intercept method

Using the sense of smell to assist in the identification of some genera and species

Expected outcomes  

Assessment of the current state of the vegetation immediately following the removal of livestock will produce a vegetation baseline dataset. The resurveying of plots will take place intermittently.

In 2023 we plan to survey the fence-line contrast between the SKA property and adjacent properties. We will use the recently developed vegetation map and classification to guide the placement of these survey plots. In this way, the survey plots within the SKA property and on the adjacent farmland will be comparable as they will both represent the same vegetation community under different grazing pressures.

Subsequent surveys in the decades ahead will allow for the tracking of vegetation change over time on the land devoid of livestock and on the land still farmed with livestock. The data will be uploaded on the SAEON data portal for future scientific investigation. These data may also be used by the South African Radio Astronomy Observatory (SARAO), South African National Parks (SANParks) and the farming community to inform management decisions.

Challenges in accessing various parts of the property  

The heavy rains that followed the drought damaged the roads and travelling time increased, sometimes requiring us to walk long distances. We also had to climb steep inselberg slopes to access sites at higher elevations. It was often challenging to navigate the rugged terrain to get to sites. Many hectares of the property have been invaded by Prosopis, which forms impenetrable thickets that also make it challenging to access some parts of the property.

Dense stands of Prosopis are found in some sections of the property

Meerkat National Park in the Northern Cape province of South Africa encompasses the Square Kilometre Array, MeerKAT and HERA telescopes (Photo: ITWeb)

Collaborator support

The support that SAEON received from SARAO, a business unit of the NRF, and the environmental management authority SANParks was generous and commendable. SAEON wishes to thank these collaborators and looks forward to continuing our research at this SAEON environmental observation platform.