Review Article

The ephemeral pans of Gras-Holpan: Mokala National Park, Northern Cape, South Africa

Nkabeng T. Mzileni, Hendrik Sithole, Hugo Bezuidenhout, Roxanne Erusan, Rodney Makwakwa
Koedoe | Vol 64, No 1 | a1709 | DOI: https://doi.org/10.4102/koedoe.v64i1.1709 | © 2022 Nkabeng T. Mzileni, Hendrik Sithole, Hugo Bezuidenhout, Roxanne Erusan, Rodney Makwakwa | This work is licensed under CC Attribution 4.0
Submitted: 12 January 2022 | Published: 09 December 2022

About the author(s)

Nkabeng T. Mzileni, Conservation Services Division, Scientific Services, South African National Parks (SANParks), Kimberley, South Africa
Hendrik Sithole, Conservation Services Division, Scientific Services, South African National Parks (SANParks), Kimberley, South Africa
Hugo Bezuidenhout, Conservation Services Division, Scientific Services, South African National Parks (SANParks), Kimberley, South Africa; and, Department of Environmental Sciences, Applied Behavioural Ecology and Ecosystem Research Unit, University of South Africa, Johannesburg, South Africa
Roxanne Erusan, Conservation Services Division, Scientific Services, South African National Parks (SANParks), Kimberley, South Africa
Rodney Makwakwa, Conservation Services Division, Scientific Services, South African National Parks (SANParks), Kimberley, South Africa

Abstract

Ephemeral pans are transient natural habitats with harsh conditions found in semi-arid regions. These pans endure high evaporation rates, extreme temperatures and an overflow of water. Pans are characterised by dry land becoming submerged in water temporarily (flood-like) followed by a prolonged period absent of water (drought-like). Ephemeral pans are unique habitats that are essentially transient habitats from a freshwater system to increased salinity and eventually a dry landscape. Biodiversity associated with these pans must adapt to the transient environmental conditions. Unique adaptations of the biota for these habitats allow them to withstand extreme conditions. The objective of this study was to (1) identify changes in the water quality over time in the pans, to (2) identify succession of macro-invertebrates and (3) identify the water quality parameters of pans as drivers of macro-invertebrate assemblages. A total of five pans were measured in the Northern Cape province of South Africa located on the Savanna and Nama-Karoo biomes within a 4500 ha area. The measurements taken included water quality variables (pH, salinity, total dissolved solids [TDS]), taxon diversity and richness of macro-invertebrates and aquatic birdlife. Evaporation rate between the pans varied with time. There was a difference in the macro-invertebrate taxon richness between the pans. Macro-invertebrate taxon succession was observed over time and some macro-invertebrates showed confinement to pans of a particular biome. It was found that pH was significantly the most contributing factor to the taxon richness and diversity of the macro-invertebrates recorded, while the salinity and TDS increased with time as water evaporated.

Conservation implications: The shrimps (fairy, clam and tadpole) were unique to the Nama-Karoo pans. It was found that pH (p < 0.05) was the most contributing factor to the taxon richness and diversity of the macro-invertebrates recorded, and salinity and TDS increased with time as water evaporated.


Keywords

ephemeral pans; transient; macro-invertebrate; water quality; salinity; pH

Metrics

Total abstract views: 1909
Total article views: 1590


Crossref Citations

No related citations found.