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​​A Journey Through South Africa’s Ecosystems

From snow-capped mountain peaks to red desert sands, South Africa’s ecosystems are some of the world’s most biodiverse environments

JUNE 4, 2021 | Written by Zoë Chapman Poulsen.

As we celebrate Environment Month, we take you on a virtual tour of South Africa’s diverse range of different biomes from towering forest to arid deserts on our #BotSocBlog.

Above: Most thicket trees produce berries, as CREW’s Groen Sebenza intern Mzukisi Beja finds out. Photo: Rupert Koopman

Thicket

Found only in South Africa’s Eastern and Western Cape, Thicket is restricted to small patches throughout the world but has a unique expression in its Succulent form in the Eastern Cape. It is easily recognised as a largely impenetrable shrubland or woodland dominated by spiny and succulent shrubs and trees, reaching a height of around three metres.

Many of the large shrubs and trees found in thicket are grazed by large mammals such as elephants, rhinoceros and kudu. Rainfall occurs year round in this environment, but is unpredictable with long periods of drought being common.

Most thicket trees and shrubs produce berries containing their seeds, that allows them to be dispersed by attracting fruit-eating birds such as mousebirds to feed on them.

Above: Plants in the desert regions, such as the Richtersveld, are adapted to survive extreme temperatures. Photo: Tina Vlok, LoveGreen Communications

Desert

Perhaps the most well-known ‘desert’ in South Africa is the Kalahari, but in fact this vast area of rolling red dune sands is actually semi-desert because of its relatively high rainfall.  

The only true desert areas in South Africa extend from the west coast of the country near the mouth of the Gariep (Orange) River eastwards to around the small Northern Cape town of Pofadder.  

Plants need special adaptations to survive the extremes of temperature and aridity in this environment. Some large succulent species such as halfmens (Pachypodium namaquanum) survive by having large internal stores of water to survive long periods of drought.

Above: Grasslands, such as the Mpumalanga grassland in the Dullstroom region, are highly biodiverse, and include orchids and bulbs. Photo: Donovan Kirkwood

Grasslands

Covering almost one third of our country’s land surface, South Africa’s Grassland Biome is the second largest of the country’s biomes. Grasslands are found across South Africa from the highveld southwards to inland areas of the Eastern Cape.

Although structurally dominated by grasses, South Africa’s grasslands are highly biodiverse with a rich flora second only in diversity to the Fynbos Biome. Different grassland types are classified as being either dry or moist grasslands, or whether they are found on different types of geology.

South Africa’s grasslands have an unusually high diversity of orchids and bulbs, many of which flower during the summer months. Fire plays an important role in the ecosystem, triggering new growth in grasses and preventing trees becoming established in the ecosystem.

Above: The Indian Ocean Coastal Belt consists of subtropical coastal forest and rolling grasslands, including Matting Rush (Juncus kraussii). Photo: Tony Dickson

Indian Ocean Coastal Belt

South Africa’s Indian Ocean Coastal Belt Biome runs in a narrow strip along the eastern coastline from KwaZulu-Natal southwards into the Eastern Cape. It comprises several different ecosystems but is considered a separate biome due to its sub-tropical climate.  

Rolling grassland landscapes in this part of the country are interspersed by deep forested gorges, particularly along the coastline of Pondoland. Much of this forest is subtropical coastal forest as well as several areas of mangrove forest.

Above: Many forests may be relatively species poor, but they still contain beauties such as the Haemanthus albiflos. Photo: Zoë Chapman Poulsen

Forest

Although only 0.56% of South Africa’s landmass has the conditions necessary for indigenous forest, it remains an important part of the environment in several of South Africa’s biomes.  

Forest in South Africa ranges from being relatively species poor in the far southwest of the country where it exists on boulder screes and kloofs in areas of fynbos where fire is excluded, to extensive tracts of more biodiverse forest in areas such as the Garden Route.

Here vast Outeniqua Yellowwood trees (Afrocarpus falcatus) that can be hundreds of years old tower above the forest canopy. More observant visitors may be lucky enough to see flashes of green and red of the Knysna Turaco as they fly through the forest.

Left: Leucadendron salignum. Right: Erica jacksoniana in the Hottentots Holland Nature Reserve near Landdroskop. Photos: Rupert Koopman

Fynbos

Found in the lowlands and mountains of the Cape, South Africa’s Fynbos Biome is home to one of the world’s richest floras. These fine-leaved shrublands may look dull from a distance but are in fact home to more than 9 000 different plant species, two thirds of which are endemic to the area and found nowhere else on earth.

Fynbos vegetation is both fire prone and fire adapted, and fires should ideally move through the landscape at an interval of 10-14 years to keep the vegetation in optimum condition. Chemicals from the smoke produced during fires trigger the germination of many different fynbos seeds.

Above: The semi-arid Nama Karoo is found across much of South Africa’s interior. Photo: Sam Jack

Nama Karoo

South Africa’s Nama Karoo characterises much of the interior of South Africa. This semi-arid ecosystem has relatively low rainfall and frequent droughts, combined with bitterly cold temperatures during the southern hemisphere winter.  

Much of the vegetation comprises low shrubs interspersed with ephemeral grasses. The shrubs act as ‘nurse plants’ for other smaller species to grow underneath, offering some protection from the hot Karoo sun.

Large herds of game such as springbok once roamed these landscapes, but today the main land use is farming of sheep and goats.

Above: Savannas are characterised by an open mix of trees and shrubs, with an understorey of grasses. Photo: Donovan Kirkwood

Savanna

Savannas are perhaps one of South Africa’s most archetypal vegetation types, often being thought of alongside big game animals in reserves such as Kruger National Park.

They are characterised by a relatively open mix of trees and shrubs along with an understorey of grasses. This vegetation is dominated by fire, often burning at the end of the dry season when fires are started by lightning strikes.

Above: The Succulent Karoo, including Knersvlakte’s floral displays, is known for extraordinary diversity. Photo: Rupert Koopman

Succulent Karoo

South Africa’s Succulent Karoo is one of the country’s three biodiversity hotspots, known for its extraordinary diversity of succulent plant species.

Around 6 350 vascular plant species are found in the Succulent Karoo, of which more than 40% are endemic to the biome and therefore found nowhere else on earth.

Polar Desert & Subantarctic Tundra

Relatively few people realise that there are two subantarctic islands that form part of South Africa, namely the Prince Edward Islands.

Comprising the larger Marion Island and the smaller Prince Edward Island, the Prince Edward island archipelago is located between the African and Antarctic continental landmasses. Some of the warmest subantarctic islands, temperatures here are relatively stable through the year, but rarely exceed 7°C.  

Both islands are volcanic with the upper slopes covered in snow throughout the year. Marion Island and Prince Edward Island are home to 22 and 21 indigenous vascular plant species respectively.

The majority of the flora comprises mosses (100 species), liverworts (42 species) and lichens (100 species). Despite this, the vegetation is relatively varied with several different plant communities found here.