Forest biomes of Southern Africa

ABSTRACT

The forests of South Africa and the neighbouring countries, including Lesotho, eSwatini, Namibia, Botswana, Zimbabwe, and Mozambique (south of the Zambezi River), were mapped and classified according to the global system of biomes. The new four-tier hierarchical biome system suggested in this paper includes zonobiome, global biome, continental biome (all recognised earlier), and regional biome – a novel biome category. The existing spatial coverages of the forests were revised and considerably improved, both in terms of forest-patch coverage and mapping precision. Southern Africa is home to three zonal forest types, namely Subtropical Forests (Zonobiome I), Tropical Dry Forest (TDF; Zonobiome II) and Afrotemperate Forests (Zonobiome X). These three biomes are characterised by unique bioclimatic envelopes. Five, two, and eight regional biomes, respectively, have been recognised within these zonal biomes. Recognition of the Zonobiome I and the global biome Tropical Dry Forests in southern Africa is novel and expands our knowledge of the biome structure of African biotic communities. The system of the azonal regional biomes is also new and comprehensively covers the variability of the azonal helobiomes (riparian woodlands and swamp forests), mangroves, and azonal coastal forests. In total, 11 azonal regional biomes have been recognised in the study area. The forest biomes in southern Africa were captured in our electronic map in the form of more than 60 000 polygons, covering 42 416 km² (1.27% of the study area). No less than 83% of these forests occur in the territory of southern Mozambique.

Abbreviations: for the abbreviation of the biome units, see Table 1; CE: centre of endemism; IOCB: Indian Ocean Coastal Belt; MBSA: the area of the Map of Biomes of Southern Africa; VegMap2006 and VegMap2018: Vegetation Map of South Africa, Lesotho and Swaziland (as released in respective years); for the meaning of the codes of the biome units see Table 1, and for the meaning of the abbreviations of climatic characteristics see Appendix S1

KEYWORDS:

• Afrotemperate forest
• azonal forest
• Botswana
• continental biome
• Mozambique
• Namibia
• regional biome
• South Africa
• subtropical forest
• Zimbabwe

Acknowledgements

We thank the Centre for Geographical Analysis (CGA) [www.sun.ac.za/cga], Stellenbosch University for GIS assistance. Johana Makinta (DAFF, Pretoria, South Africa) and Boyd Escott (Ezemvelo KZN Wildlife, Pietermaritzburg, South Africa) kindly mediated access to spatial data. Federico Luebert (Santiago, Chile) initially helped with the development of the climate diagram app. John Burrows, Wayne Matthews, Marc Stalmans and Wessel Swanepoel kindly contributed some photographs. The authors thank the reviewers and Chris Lusk, the Editor, for their helpful suggestions in improving our manuscript. Helene van Niekerk kindly performed the final linguistic revision of the manuscript.

Data availability

The simplified version of the forest geodatabase can be viewed using an ArcGIS online app using the following link: http://bit.ly/forests2021

Those interested in acquiring the detailed geodatabase are encouraged to contact the first author of this paper.

Disclosure statement

The authors declare that they do not have any conflict of interest.

Additional information

Funding

LM acknowledges the support of the Iluka Chair in Vegetation Science and Biogeography at The University of Western Australia and Murdoch University, Perth. JBA acknowledges the support of the National Research Foundation of South Africa to the DSI/NRF Research Chair in Shallow Water Ecosystems supported and associated funding (UID 84375).