eMalangeni Forest: raphia australis

Showing posts with label raphia australis. Show all posts

Thursday, 29 April 2021

What is a peat swamp forest?

Peat swamp forests known as idobo in the Zulu language are moist forests that are formed where waterlogged soil prevents dead leaves and wood from fully decomposing. Over time, this creates a thick layer of acidic peat inhabited by unique plant communities adapted to these wet, acidic, nutrient and oxygen poor soils.

Swamp fig Ficus trichopoda growing on the banks of the aManzimnyama river in the eMalangeni peat swamp forest

Peat swamp forests form in areas where saturated soils or frequent flooding prevent organic material from fully decomposing. As this organic material slowly accumulates, it retains even more water through capillary action, up to 13 times its weight, acting as a giant sponge that holds in the moisture. Peat swamps known as ixhaphozi in the Zulu language eventually form a dome of wet organic material that can rise above the surrounding flood levels.

It takes thousands of years for peatlands to form, with organic matter accumulating at 0.5 – 2 mm per year . Peat layers over 4 meters are common, while depths of up to 20 meters have been reported.

a photograph of the water well known as Kwa Ginga that has been used by the eMalangeni community for over 100 years in the eMalangeni peat swamp forest that was named after the royal son of Makhuza Tembe

Above is a photograph of the water well known as Kwa Ginga that has been used by the eMalangeni community for over 100 years in the eMalangeni peat swamp forest. the well was named after the royal son of Makhuza Tembe

The unique hydrology of this habitat provides a critical buffer against flooding during the wet season, and insurance against drought in the dry season. The swamp retains heavy rainfall and slowly releases the moisture over an extended period of time. As climate change results in more extreme weather events and irregular precipitation, this ecosystem service is becoming even more critical.

The jewel of the eMalangeni Forest Euphaedra neophron, the gold banded forester, is a butterfly in the family Nymphalidae

In many ways, Peat swamp forests are similar to other tropical and sub-tropical lowland forests such as in the size and density of large trees. Unique biological communities are specially adapted to thrive in the flooded, oxygen poor environment.

Many tree species have large buttresses and Seepage of black water stained by tannins in the eMalangeni peat swamp forest to hold themselves up in the soft peat soil. Others have pneumatophores or are covered with lenticels at the base of the stem to permit gas exchange with the air, as soils are waterlogged and often inundated.

The red mangrove Rhizophora mucronata with prop roots to support it in the unstable peat soil

Wetland associated plants are also very common in the understory and on the forest floor, epiphytes growing on the trees right up into the canopy are numerous, such as ferns and orchids.

The epiphytic fern Microsorum punctatum growing on threes in the eMalangeni peat Swamp forest in the Kosi Bay System

Peat Swamp Forests supply numerous ecosystem services to human communities. These are natural services that are beneficial to humans but not paid for directly, these services include timber and non timber forest products such as honey, nuts, fruits, medicines, latex, dyes, and fiber. Peat swamps also provide fresh water and fish to local communities.

Peat Swamp forests regulate landscape hydrology, and have been described as “landscape sponges”, absorbing excess rainwater during wet seasons and during extreme storm events, and steadily releasing stored water during dry spells or droughts. They also serve as biofilters which trap sediments and excess nutrient runoff from agricultural activities upstream. In their natural state, peat swamps are also globally significant sinks of atmospheric carbon.

The Narina trogon Apaloderma narina is a most spectacular forest bird that is to be found in the eMalangeni peat swamp forest.

In South Africa peat swamp forests are highly threatened ecosystems, being the second rarest forest type in the whole country and only occur in isolated patches from the Mozambique border a few kilometers north of the Kosi Bay System and the eMalangeni peat swamp forest to just south of the Msikaba River in the Eastern Cape

The coastal peat swamp forests on the flat coastal plain of Maputaland which include the eMalangeni coastal peat swamp forest the largest of the peat swamp forests represent seventy five percent of all the swamp forest found in South Africa.

The eMalangeni coastal peat swamp forest which has a total area of 880 ha feeds the Siyadla- aManzimnyama river that flows through it is the largest peat swamp forest in South Africa. The eMalangeni coastal peat swamp forest which is situated immediately south of lake aManzimnyama is the main source of fresh water for the Kosi Bay Lake System.

The water that is released by the eMalangeni peat forest into the aManzimnyama river (black water river) is stained dark brown by the tannins that leach from the fallen leaves and peat, hence the name aManzimnyama the Zulu name for black water.

The aManzimnyama river, black water river that flows through the eMalangeni peat swamp forest

The eMalangeni peat swamp forest displays a gradient between wet and dry swamp forest. Raphia australis, Syzygium cordatum, Schefflera umbellifera generally grow under drier conditions, while Syzygium cordatum, Voacanga thouarsii grow in intermediate conditions and Ficus trichopoda dominate the Riverine area of the forest.

The drier swamp forest on the western shore of Lake aManzimnyama has large stands of the endemic Kosi Bay Palm, Raphia australis palms. Syzygium cordatum which exhibits a grade of hydrological preferences, is mostly absent in the very dry Raphia australis and very wet Ficus trichopoda dominated vegetation areas.

The Kosi Bay palm Raphia australis growing in the eMalangeni peat swamp forest

Heavily disturbed areas of the forest which were caused primarily due to previous agricultural practices are characterized by a general lack of a fully developed tree canopy as well as hydrological modifications made to the peat by means of drainage ditches. Natural gaps in the forest are created where stands of the monocarpic Raphia australis palms die and fall over after flowering.

Traditionally the light and durable wood of the endemic Raphia australis palms has been a very important component in the livelihood of the local peoples, the collection of fallen rachi is used for construction material for houses as well as canoes and rafts to cross the aManzimnyama river.

A traditional boat used on the lakes at Kosi Bay made of the leaf rachi of the Kosi Bay palm Raphia australis

In the past traditional farming practices enabled the local communities who have been relocated to live in harmony with their wetlands for several generations, as they rotated their gardens on a chosen peatland and still have wetland habitat that remain intact in spite of their presence over several centuries.

Tourism in this largely pristine peat swamp forest area that has been placed under the protection of the iSimangaliso Wetland Park Authority is playing an increasingly important role in the local economy as access and tourist numbers improve due to better infrastructure, such as new roads and lodges, and wider circulated publicity.

An African Jacana Actophilornis africana and young on the lily pads of the blue water lily Nymphaea nouchali in the eMalangeni peat forest

Guided excursions that offer far more scientific knowledge and interesting facts in regards to the plants birds animals and other creatures encountered in the forest than the usual guided can be conducted in English, Zulu and German into the eMalangeni Swamp Forest and surrounding area including the nearby Tembe Elephant Park can be arranged and tailored to the individual needs of the client/s no matter at which establishment one will be staying at while at Kosi Bay. Please visit one of my websites for contact details.

Michael Hickman

29.04.21

please visit my websites

www.ecoman.co.za

www.hlem.co.za

as well as my other blogs at

http://luthulienvironment.blogspot.com/

http://ecomandurban.blogspot.com/

http://ecoman.co.za/projects/emalangeni.html

https://www.hlem.co.za/emalangeni.html

Sunday, 28 March 2021

The eMalangeni Peat Swamp Forest

This blog is to bring to you the rich and varied natural wonders and local human traditions that can be found in and around the eMalangeni Peat Swamp forest immediately south of lake Amanzimnyama at Kosi Bay.

The Gorgeous Bush-shrike Telophorus quadricolor is another of the forest birds that are more often heard than seen but if one has some patience these birds will appear as if by magic out of the undergrowth.

The eMalangeni coastal peat swamp forest with a total area of 880 ha occurs adjacent to the Siyadla / aManzimnyama river, immediately south of lake aManzimnyama is the largest peat swamp forest in South Africa, it is also the main source of fresh water for the Kosi Bay Lake System. Coastal peat swamp forests are fresh water forested wetlands that are established on peat soils in close proximity to the Indian Ocean on the north east coast of South Africa. In South Africa Coastal peat swamps forests are highly threatened ecosystems, being the second rarest forest type in the whole country and only occur in isolated patches from the Mozambique border to just south of the Msikaba River in the Eastern Cape. The coastal peat swamp forests on the flat coastal plain of Maputaland which include the eMalangeni coastal peat swamp forest represent seventy five percent of all the swamp forest found in South Africa.

Pont across the aManzimnyama river in the eMalangeni Forest

The traditional Pont made of the leaves of the Raphia Palm belonging to the local community that is used to cross the aManzimnyama River in the heart of the eMalangeni Forest

As previously stated the eMalangeni peat swamp forest is an extensive swamp forest in the Kosi Bay system. Being the largest swamp forests in the country and due to the rarity of this forest type, it adds considerable importance to the Kosi system. Common tree species include the giant raffia palm Raphia australis, Syzygium cordatum, Ficus trichopoda, Englerophytum natalense, Voacanga thouarsii and Rauvolfia caffra as large trees, with Rapanea melanophleos, Myrica serrata and Halleria lucida as sub-canopy. On the forest margins one can find Sphedamnocarpus pruriens.

On the forest margins one can find Sphedamnocarpus pruriens

Ferns and other plants such as the reed like liana Flagellaria guineensis. The extensive groves of raffia palms in the forest support the largest population of breeding Palm-nut Vultures Gypohierax angolensis in South Africa. The ferns, Microsorum scolopendria, Stenochlaena tenuifolia and Nephrolepis biserrata as well as Zamioculcas zamiifolia,

Zamioculcas zamiifolia the very popular indoor plant growing in its natural habitat in the eMalangeni forest at Kosi Bay South Africa

Sansevieria concinna, Scadoxus multiflorus, Coleotrype natalensis, Drimiopsis maculata, Smilax anceps and many other plants cover the forest floor. The trees are covered in epiphytes such as the fern Microsorum punctatum and orchids such as Cyrtorchis arcuata, Aerangis mystacidii and Polystachya concreta, commonly known as the Yellow Helmet Orchid

The epiphytic fern Microsorum punctatum growing in the eMalangeni Forest at Kosi Bay

On the forest margins and adjoining grasslands many colourful flowering plants can be seen.

Crinum stuhlmannii subsp. delagoense growing on the margins of emalangeni forest at kosi bay

The Kosi Bay System

Kosi Bay in South Africa is a complex estuary-linked lake system that stretches from the Mozambique border in the north, to Lake Amanzimnyama, in the south, that has been transformed into circular bays and lagoons containing fresh or brackish water, separated from one another by low beach barriers.

Traditional boat made from Raphia palm leaves on the shore of Lake aManzimnyama

The system comprises four roughly circular, interconnected lakes being Makhawulani, Mpungwini, Nhlange and aManzimnyama, a broad channel leading to an estuary that opens to the Indian Ocean, and three extensive areas of swamp. Two principal rivers, Siyadla and Nswamanzi, feed into it. This is also the only system in South Africa in which five species of mangrove are found.

The aManzimnyama river the flows throught the eMalangeni Forest into lake aManzimnyama

The climate is subtropical, with maximum temperatures varying between 23 °C and 30 °C. Rainfall averages between 670 and 1,100 mm p.a. and falls mostly in October–March.

Birds

The bird life of the Kosi system is essentially forest associated and is prolific, the list of 247 species for approximately 85 are water or estuary associated. Amongst the wetland and water associated species some are rare, such as the white winged Flufftail and the Whitebacked Night Heron, Gorsachius leuconotus.

a photo of crested guineafowl (Guttera pucherani) taken in the eMalangeni Forest Kosi Bay Complex South Africa

A photo of a Crested Guineafowl (Guttera pucherani) taken in the eMalangeni Forest Kosi Bay Complex South Africa

The largest colony of Palm-nut Vultures Gypohierax angolensis in South Africa is to be found in this forest. Several bird species at Kosi area the most southerly limits of their distribution and are not encountered elsewhere in South Africa such as the Livingstone’s Turaco, Tauraco livingstonii.

Orchids

There is a fairly large number of orchid species both epiphytes such as Aerangis mystacidii and Cyrtorchis arcuata as well as terrestrial orchids such as Oeceoclades lonchophylla are to be found in the eMalangeni forest. There a number of tropical African orchid species found in this forest marks the South limit of their occurrence.

The epiphytic orchid Cyrtorchis arcuata growing in the eMalangeni Forest at Kosi Bay

Animals

Hippo, crocodiles, monkeys, bush pig, bush buck and many others are be encountered in the forest.

Local Human Traditions.

Zulu, Tonga people of the Tembe Tribe and a people known as the amagonde speaking a language isigonde which is fast dying out and is now only spoke by a few older people have been living next to the the eMalangeni Swamp Forest for centuries. These peoples relied heavily on the eMalangeni coastal peat swamp forest as a source of fresh drinking water and as the only available productive land for cultivating crops. The inclined swamp forest valley slopes facilitate easy drainage of the peat and resulted in traditional cultivation techniques of cutting drainage ditches and constructing raised beds. This gradient of hydrological modification enabled the gardening of a wide variety of crops, with bananas Musa xparadisiaca and amadumbe Colocasia esculenta being the most common.