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• South Africa is not spared from the adverse effects of climate change which alters the ecosystem and have a ripple effect on food security. • This paper reviewed the impacts of climate change on the phenology, physiology, and economic benefits of wild fruits and vegetables in South Africa. • The possible productivity of wild fruits and vegetables was evaluated with spatial-based data through land use/land cover which showed that South Africa had varied vegetation and land cover dynamics. • There is a need to develop cultivation strategies for edible wild fruits and vegetables to expand knowledge and create options in utilizing the wild species. • This will boost the country's economy, help to improve diet, and can play a crucial role in food security. Overdependence on exotic plant species constitutes a major setback for the consumption of wild fruits and vegetables among South Africans. The country is not spared from the adverse effects of climate change which play a substantial role in altering the ecosystem and have a ripple effect on food security. Wild fruits and vegetables have been identified to be underutilized despite the country's struggle in nourishing its population. This paper reviewed the impacts of climate change on the phenology, physiology, and economic benefits of wild fruits and vegetables in South Africa. Furthermore, spatial-based data was used to evaluate the possible productivity of wild fruits and vegetables through land use/land cover (LULC) assessment. The result showed that South Africa had varied vegetation and land cover dynamics. For example, Northern Cape and Western Cape Provinces are dominated by shrubland and barren land, thus unsuitable for fruit and vegetable production. In contrast, Limpopo, North-West, Mpumalanga, Gauteng, Free State, some parts of KwaZulu-Natal and Eastern Cape Provinces are covered with grassland and cultivated areas which made them good for vegetable farming and potential ground for wild fruit and vegetable cultivation. Thus, there is a need to develop cultivation strategies for edible wild fruits and vegetables with known nutritional characteristics to expand knowledge about nutritional benefits and options in utilizing the wild species. This will boost the country's economy, help to improve diet, and can play a crucial role in food security. [ABSTRACT FROM AUTHOR]

• The highly invasive Nassella neesiana, N. tenuissima and N. trichotoma are naturalised in high altitude mountain grasslands of South Africa. • The current knowledge of Nassella invasion dynamics is based on limited research mainly done before the 1990s or research being done in Australia and New Zealand. • Current control methods are not coping with invasions. • There's a potential to use biological agents to control Nassella invasions. • There are many knowledge gaps that require urgent research in order to effectively manage invasions. Three species of Nassella have naturalized in South Africa. Nassella trichotoma and N. tenuissima are declared weeds under category 1b of the National Environmental Management: Biodiversity Act (NEM:BA) and occur mainly in the montane grasslands of the Western and Eastern Cape provinces. Nassella neesiana is not listed in NEM:BA but is naturalized in the Eastern Cape, Western Cape and Free State provinces. Research conducted in the 1970s and 1980s led to vigorous government-funded awareness and control campaigns which ended in 2000. No research on Nassella distribution or control has been undertaken since then. Despite this hiatus, Nassella remains a dangerous genus in southern Africa, given the serious impacts of these species in similar social-ecological systems in Australia and New Zealand. This paper presents a synthesis of available information about Nassella invasions in South Africa and identifies research gaps. It specifically addresses these questions: What identification issues exist? What is the current spatial distribution of Nassella ? What is the autecology of the genus? What are the social-ecological impacts of Nassella ? What control measures are currently applied and what are their strengths and limitations? What do we know about Nassella distribution and its response to climate change? This paper highlights many knowledge gaps about Nassella, such as the species' current distribution range, field identification and detection difficulties, and the uncoordinated control efforts that require urgent research to inform an effective management response. [ABSTRACT FROM AUTHOR]

• Mallomonas corymbosa, M. kenyana and M. porte-ferreae were found in the Vaal River, South Africa. • Cell morphology and geographical distribution of each species are presented. • Water quality of the Vaal river at the time of sampling is presented. • The finding of M. corymbosa represents the first record of this species in Africa. • M. kenyana, a tropical/subtropical species, were found in temperate regions in South Africa. This paper reports on the presence of three Mallomonas species (Phylum Ochrophyta) in the Vaal River, South Africa. Scanning electron microscope observations of entire cells with intact scales and bristles allowed accurate identifications of M. corymbosa, M. kenyana and M. portae-ferreae. Descriptions and dimensions of each of the three species are given, their geographical distribution is discussed and physico-chemistry of the water at the time of their finding is presented. M. corymbosa was recorded for the first time in Africa, expanding its known geographical distribution to an additional continent. The climatic preferences of the tropical and subtropical species, M. kenyana were extended to temperate regions in South Africa. These species were present under eutrophic to hypertrophic conditions, a water temperature of 25.4 °C, neutral to slightly alkaline water (pH 7.25) and a conductivity value of 440 µS/cm. [ABSTRACT FROM AUTHOR]

South Africa's unique flora and extensive use of African traditional medicines has created a unique research opportunity on medicinal plants for local and international scientists. In this paper, submitted to a special issue of South African Journal of Botany (SAJB) dedicated to "sub-Saharan Ethnobotany", we aim to explore the research landscape on medicinal plant research as published in SAJB. A bibliometric assessment (1982–2017) showed that medicinal plant research represents 24% of the published volume in SAJB and that contributions on this topic are increasing exponentially. Although most papers are broad-based invitro screening studies, the range of topics covered is impressive. Antimicrobial (41%) and anti-oxidant (21%) studies dominate the research space with fewer studies focusing on diseases highly relevant to the African continent, e.g. malaria (3%) and tuberculosis (2%). Although the SAJB has contributed greatly to disseminating knowledge on important species (e.g. Aspalathus and Cyclopia) several taxa of potential economic relevance remain poorly investigated (e.g. Adansonia , Bulbine etc.). The citation footprint and authorship networks which have been established attest the pivotal role the SAJB has played to build research capacity and create awareness in this important field of research. • Medicinal plant papers contributed 24% of papers published in SAJB (1982–2017). • The 629 papers considered attracted 6313 citations. • In vitro studies represented 89% of experimental papers. • Highest number of published papers were antimicrobial (41%) and anti-oxidant (21%). • Few studies focused on relevant diseases like tuberculosis (2%) and malaria (3%). [ABSTRACT FROM AUTHOR]

• Cowpea is a highly valued fruit and leafy vegetable crop contributing to food, nutrition, and health security. • Low cowpea production and productivity in sub-Saharan Africa and globally are due to a lack of improved cultivars with multiple disease, and insect pest resistance and drought tolerant; moreover, there is a lack of seed system research in cowpea. • The extensive phenotypic and genotypic variation found in cowpea genetic resources is useful for the development of cultivars with enhanced grain yield, leafy yield and nutritional values as well as drought tolerant. Despite the contribution of cowpeas to food security and the crop's numerous nutritional and health attributes, consumers in South Africa have labelled cowpeas, among other leguminous crops as a "poor people's food" ; this contributed to the gradual decline in the cultivation and use of the crop. This, in turn, resulted in the observed high reliance on limited number of plant based protein crops and excessive consumption of livestock products. In this paper, three aspects are interrogated, i.e., genetic resource management, production constraints as well as the trade performance and consumption of cowpeas in South Africa. A clear understanding of these aspects renders an informed decision upon which recommendations for the necessary practical interventions that are needed to be put in place to spur the development of target products and cowpea's value chain. The assessment of genetic resource management and seed production constraints of cowpeas was based on a review of relevant literature, while descriptive analysis of secondary data spanning a period of 10 years (2010-2019) obtained from Trade Map and FAOSTAT databases was used to interrogate the trade performance and consumption of cowpeas. Findings reveal that seed production constraints are largely anchored on the limited attention government and policy making institutions have accorded to the seed system of orphaned crops, thereby compromising their potential by failing to supply affordable good quality seeds to smallholder and commercial farmers. However, South Africa has one of the largest and most diverse collections of cowpea germplasm housed at the Agricultural Research Council. With regard to trade performance and consumption, results show that South Africa is a net exporter of cowpeas, with a 10 years' period annual average worth R2.9 million. Given that South Africa does not re-export cowpeas, yet on average 4848 tonnes are produced annually, it is a clear indication that the country produces lightly more than what is consumed domestically – on average 4634 tonnes per annum. Therefore, recommendation is made to bolster cowpea production and productivity through mainstreaming the legume seed system towards boosting local and export markets as well as strongly enhancing local consumption by creating awareness of the nutritional and health benefits of cowpeas. Furthermore, there is a need to increase awareness about the nutritional and health benefits of cowpeas and other leguminous crops, among other socio-economic benefits. This is important in spurring cowpeas consumption domestically, while countering the over reliance on animal products as protein sources and the associated risks such as such as high greenhouse gas emissions and obesity for people. [ABSTRACT FROM AUTHOR]

Food security is threatened in Southern Africa, because of unpredictable droughts and higher summer temperatures brought on by climate change and global warming. Durable and hardy plants that grow easily and quickly in such conditions must be adopted to ensure sustainable and reliable food supplies. The young cladodes (nopalitos) from the cactus pear plant, which adapts to hot and dry climates, is an underutilised alternative food source that can serve as a healthy vegetable. It thrives in many environments such as deserts, below sea level, high altitude regions and tropical regions with temperatures above 50°C. Nopalitos are a traditional staple vegetable and have been consumed in Mexico for over 9000 years. However, it is underutilised and unknown as an alternative vegetable in Africa. Research on the physiochemical and nutritional content has been conducted. However, the information on harvesting nopalitos from cultivars available in South Africa for optimal edible quality is not available. Good quality nopalitos are young, thin, bright green, soft, fresh and not too sour or slimy. This paper aims to identify the effect of and the interaction between size, cultivar and harvesting season to obtain optimal eating quality. Data were obtained for two cultivars (Morado and Fusicaulis) at 9 cm, 12 cm, 15 cm, 18 cm, 21 cm and 24 cm, which were harvested in spring (October) and autumn (March) over two years. The quality characteristics were translated into the measurable attributes of morphology (weight, width, diameter, volume and surface area), texture (firmness and compressibility), colour (L*, a*, b*, C*and h°), turgidity (moisture content, mucilage yield and viscosity) and gustatory (percentage titratable acidity, pH and total soluble solids). ANOVA and Principal Component Analyses were performed to determine significant differences and interactions between the length groups, two cultivars and two seasons. The results showed that the size, cultivar and season influenced the edible characteristics. Both cultivars were most tender at 15 cm and presented the best edible qualities in spring. Morado showed better colour, turgidity and gustatory qualities. Morado was thinner, a brighter green colour, less sour and less slimy compared to Fusicaulis nopalitos. • Nopalito quality is highly influenced by harvest size, cultivar and season. • At 15 cm, nopalitos from both Morado and Fusicaulis were the most tender. • Morado nopalitos was the preferred cultivar, but Fusicaulis also performed satisfactorily. • Spring harvest was preferable, but autumn harvest nopalitos were acceptable. • Morado was thinner, a brighter green colour, less sour and less slimy. [ABSTRACT FROM AUTHOR]

Over the past decade, a series of controversies has arisen about equity and justice in the rooibos industry, centred both on the biological resource and on the traditional use and knowledge that fostered the growth of this lucrative trade. Accusations of biopiracy, meaning the misappropriation and patenting of genetic resources and knowledge without consent, have taken centre stage, leading to a reassessment of the conditions under which rooibos is traded. Claiming to be the primary holders of traditional knowledge relating to rooibos, indigenous San and Khoi have also launched demands—to date unmet—for a stake in rooibos benefits. Meanwhile, small-scale coloured rooibos producers, despite their involvement in fair trade, remain marginalized. All remain embedded in a political history of rooibos that is characterized by dispossession and adversity, having been propped up by the South African apartheid system. The melding of these issues with a complex and ambiguous legal framework has led to a situation described by some as “the mother” and “testing ground” of so-called access and benefit sharing. Such approaches stem in part from the Convention on Biological Diversity and its Nagoya Protocol, which lay down new and more equitable ways of treating trade in genetic resources and the use of traditional knowledge. With growing international interest in rooibos tea and its bioactive compounds, a surge of patents associated with the plant, the successful granting of geographical indication status, and threats to the industry of changing climates, ecologies and ecosystems, the stage is set for a reconceptualization and transformation of the industry. Drawing on longitudinal research over the past 20 years, this review paper aims to bring conceptual clarity and a holistic analysis to an often emotional, divided and, to date, narrowly framed debate. Through exploration of rooibos histories and traditional knowledge claims, bioprospecting and patent activities, and conservation imperatives, this paper reviews the spectrum of issues that require attention when considering access and benefit sharing in the rooibos industry and provides suggestions for a more integrative, environmentally responsive and just approach. [ABSTRACT FROM AUTHOR]

Moringa is widely distributed across the globe for its multiple uses as well as high nutritive content and great economic attributes; subsequently it has been highly commercialised. Even though moringa is fast becoming an important crop in several parts of the world, in South African context, it is not recognised for such, and is listed on the Species Under Surveillance for Possible Eradication or Containment Targets (SUSPECT) under National Environmental Management Biodiversity Act (NEM:BA), since it is not native to South Africa. Where it is established in South Africa, people perceive the numerous qualities of moringa as beneficial and this can result in conflict generation between communities and policy makers who have to safe guard against alien and invasive species spread and impact. In this paper, we review the ecological, social and legal status of moringa in South Africa, and highlight the importance of conducting research on non-native species with the focus of improving evidence base prior listing of species on national regulations. Moreover, we highlight the need to also focus on social aspects of invasive species, using a cost–benefit approach to assist in decision making regarding control, management and eradication of moringa and other non-native plants. • In South Africa, moringa is on the Species Under Surveillance for Possible Eradication or Containment Targets (SUSPECT). • Moringa has the potential to be a conflict-generating species, particularly between communities and policy makers. • Listing of non-native species under NEMBA should be guided by impact-based evidence to ascertain their risks and benefits. [ABSTRACT FROM AUTHOR]

Thesium L., section Hagnothesium is endemic to the Greater Cape Floristic Region (GCFR), South Africa. In the past there has been a propensity in revisionary work of the section Hagnothesium to split taxa into distinct species or vice-versa. Consequently, 15 different names exist although only 6 are accepted formally. Following recent molecular phylogenetic studies, the monophyly of the section Hagnothesium is now well-established but the circumscription of species within the section remains problematic given the complicated nomenclatural history which has added further confusion. In this paper we revise the section using a total evidence approach to propose a revised taxonomy. We studied both herbarium collections as well as plants in their natural populations to circumscribe species boundaries, determine their geographical ranges and estimate their conservation statuses. Species of the section Hagnothesium are dioecious, generally having four-merous campanulate flowers produced in spikes borne in bract axils and arranged along the length of branchlets, with valvate perianth lobes and a short to absent hypanthial tube. We recognise eight species, of which one is described in this study as new: T. fragile L.f., T. fruticulosum (A.W.Hill) J.C.Manning & F.Forest, T. hirtum (Sond.) Zhigila, Verboom & Muasya comb. nov., T. leptostachyum A.DC., T. longicaule Zhigila, Verboom & Muasya nom. nov. T. microcarpum A.DC., T. minus (A.W.Hill) J.C.Manning & F.Forest) and T. quartzicolum Zhigila, Verboom & Muasya sp. nov. We provide updated taxonomic keys, species descriptions, illustrations, distribution maps, new combinations, synonyms, and notes on the red list status for each species. • A review is given of Thesium section Hagnothesium (Santalaceae) an endemic clade to the GCFR. • Eight species are recognised, of which one, T. quartzicolum is described here as a new. • Key to the species in section Hagnothesium is provided • Species delimitations and nomenclatural changes are provided. • Species geographical ranges and the estimate of their conservation statuses are provided. [ABSTRACT FROM AUTHOR]

This paper reported for the first time the aroma profile and essential oil composition of eight species of Helichrysum endemic in South Africa but grown in Italy (CREA-Sanremo collection). The volatiles of all the studied Helichrysum were dominated by monoterpene hydrocarbons, except for H. basalticum , where sesquiterpene hydrocarbons was the main class of compounds with β-caryophyllene (13.7%) and α-guaiene (11.9%) as major components. Despite the great diversity of compounds obtained in the volatile emission (more than 130), only four compounds were responsible for at least 34% of the identified fraction. These compounds were: sabinene (16.0%), β-caryophyllene and α-guaiene in H. basalticum ; sabinene (57.7%) in H. foetidum ; (Z)-β-ocimene (34.6%), tricyclene (16.2%) and myrcene (10.0%) in H. incanatum ; myrcene (29.3%), tricyclene (21.5%) and limonene in H. indicum ; tricyclene (32.1%) and (E)-3-hexanol acetate (20.1%) in H. montanum ; limonene (10.3%), sabinene (8.9%), 1-decene (7.6%) and 1-hexanol (7.0%) in H. mutabile ; α- and β-pinene in H. patulum (27.6% and 44.9%, respectively) and α-pinene (36.3%) and α-fanchene(15.6%) in H. setosum. The EOs composition of these species was also different from each other with sesquiterpene compounds as the prevalent class. Valerianol (16.3%, os, in H. basalticum), ledol (16.3%, os, in H. foetidum), β-caryophyllene (11.0% and 13.4%, sh, in H. indicum and H. patulum , respectively), viridiflorol (18.3%, os, in H. montanum) and valerianol (30.1%, os in H. setosum) were found to be the main constituents. It is worthy to highlighting that the H. incarnatum EO showed a similar behaviour to that of the spontaneous emission with a predominance of monoterpene hydrocarbons (60.7% in EO vs 81.4% in VOC), both represented by (Z)-β-ocimene as main constituent. • First chemotaxonomic characterisation of eight South African Helichrysum spp. • These South African were grown in the same edaphic and climatic conditions. • Monoterpene hydrocarbons dominated VOC samples except for H. basalticum. • Sesquiterpenes had the highest percentage in seven EO samples. • Helichrysum incarnatum EO was characterised by high amount of monoterpenes. [ABSTRACT FROM AUTHOR]

Abstract Rubus L. is a highly diverse and taxonomically complex genus with a worldwide distribution. Although southern Africa is not a major centre of Rubus diversity, a number of indigenous and naturalised taxa have been recorded from the region, although their taxonomy, nomenclature and evolution are either confused or poorly studied at best. This paper represents the first results of a wider project focusing on the biosystematics of the southern African Rubus flora, and presents a taxonomic revision of the brambles of the Cape Floristic Region, including an estimation of ploidy levels. A total of eight taxa are recognised, including the two indigenous taxa R. pinnatus and R. rigidus agg., the four introduced species R. armeniacus , R. bergii , R. rosifolius and R. titanus , and two hybrids between indigenous and introduced taxa. Rubus rigidus agg. is an unresolved and variable species complex with at least two ploidy levels (5x, 6x). The hybrid taxon R. bergii × R. rigidus appears to be widespread and behaves as an independent apomictic complex. In addition, hybridization between R. bergii and R. pinnatus is relatively common in the contact zones between the two species. The two introductions Rubus armeniacus and R. titanus are recorded from South Africa for the first time. The invasive potential of the introduced species is regarded as low but the potential for hybridization by R. bergii seems to be high. An identification key, morphological descriptions, and notes on nomenclature, distribution and ecology are provided, and all taxa are illustrated. Highlights • Rubus is revised for the CFR. • Eight native and naturalised taxa are recognised. • Rubus armeniacus and R. titanus are recorded from South Africa for the first time. • All taxa are described and fully illustrated. [ABSTRACT FROM AUTHOR]

Abstract The purpose of this paper is to give an ecological description of the vegetation of the Jurisdam-Seekoegat section of the Mountain Zebra National Park in the Eastern Cape Province, South Africa. The effect of different land use practices on the vegetation composition was also investigated. Vegetation classifications and descriptions are of immense value to scientists and land managers and provide information on the composition, structure, diversity and effect of management on the different ecosystems present. The Braun-Blanquet approach was used to classify the different plant communities, while the veld condition was determined using the Ecological Index Method. Plant community data was analysed using the JUICE software package while diversity of the different plant communities was determined using the Shannon–Wiener and Gini–Simpson Indices. From a TWINSPAN analysis eight plant communities that can be grouped into six major communities were identified. Two plant communities not previously described for the Park were identified. The different plant communities can all be related to topography and effect of previous land use. Grasses and dwarf shrubs are the most prominent species. The plant communities of the rocky midslope areas achieved the highest species richness and diversity for the study area. The areas least affected by heavy grazing had a higher veld condition score than those heavily grazed by domestic animals in the past. The results of this study also emphasises the importance of resting overgrazed veld, while it seems that heavily grazed areas will not recover without further human intervention. A vegetation map of the different plant communities was produced using ArcGIS. Highlights • Vegetation classification improves our knowledge and understanding of complex ecosystems. • Rocky hilly areas act as refuge areas for vegetation with the highest diversity of plant species. • Resting of overgrazed veld in arid areas assists in veld condition recovery. • Wildlife has less of an impact on veld condition than domestic animals with continued grazing. • Overgrazing seems to alter nutrient structure of soil thereby altering vegetation composition. [ABSTRACT FROM AUTHOR]

The common wetland vegetation types categorized as temperate grassy wetlands have tall or medium tall graminoids that are found in the Highveld and other grassland areas in South Africa, but can extend into other biomes. The data on temperate grassy wetlands were extracted from a nationwide wetland vegetation database, consisting partly of historical vegetation data and partly newly collected data. A classification of these vegetation types took place using cluster analysis. Some of the vegetation data contained detailed soil parameters, which were used in canonical ordination to illustrate which environmental variables have the most impact on these vegetation types. Temperate grassy wetlands consist of twenty-five communities, which have been summarized in this paper into thirteen community groups. These wetlands occur over a wide altitudinal range as many of the species occurring in them have broad ecological amplitudes and are competitive even outside of their optimum range. The environmental variables that were the most important in explaining both the variation in the dataset and the vegetation types were wetness and altitude. [ABSTRACT FROM AUTHOR]

This paper presents the first detailed assessment of the invasive potential of Melaleuca hypericifolia Sm. in South Africa. This woody, fire-adapted shrub, native to Australia, is considered a high risk invader which could potentially occupy 4% of the country if allowed to spread. As such, it is a listed invader under South African legislation. Melaleuca hypericifolia is known to have naturalised at five sites in the Western and Eastern Cape of South Africa and several introduced but non-spreading populations represent a further risk of invasion. An integrated management approach involving mechanical and chemical control was tested on an invasive population (20.4 ha extent) on Chapman's Peak in Cape Town, Western Cape Province. Management interventions began in 2012 and were repeated annually. The number of reproducing individuals was reduced over the four year period reported on here. The treatment used was shown to be effective as no re-sprouting occurred although some plants were overlooked during clearing operations owing to the density of the surrounding native vegetation. Low detectability presents a major impediment to extirpation of the population despite the distinctive flowers and leaf arrangement of this species. We recommend the use of fire where feasible to increase visibility and stimulate seed germination. We estimate that extirpation of M. hypericifolia from the Chapman's Peak site will be possible with an annual investment of ZAR 10000 over the next 10 years. Uncertainty around the extent of plantings of Melaleuca hypericifolia around the country limits the suitability of the species as a national eradication target. However, based on the invasive risk it poses and given encouraging results from the extirpation effort as shown in this study, we conclude that site-specific extirpation is a feasible management goal for this species. [ABSTRACT FROM AUTHOR]

The South African rocky subtidal and intertidal habitats are rich in diversity and abundance of non-geniculate coralline red algae. Despite their ubiquity, they are still a comparatively poorly known group of marine organisms. Ongoing taxonomic changes have meant that the classification and characterisation of these algae have been in constant flux. In light of these ongoing changes, the aim of this paper was to reconcile the most recent publications with previous consolidated records to produce the most up-to-date keys to the non-geniculate coralline red algae of South Africa. As a consequence of ongoing taxonomic changes and additional, more focused collections, currently 45 species of non-geniculate coralline red algae, belonging to three orders (Corallinales, Hapalidiales, Sporolithales), three families (Corallinaceae, Hapalidiaceae, Sporolithaceae), seven subfamilies (Choreonematoideae, Hydrolithoideae, Lithophyloideae, Mastophoroideae, Melobesioideae, Metagoniolithoideae, Neogoniolithoideae) and 18 genera are now recognised to occur along the South African coast. South Africa has representative species from more than half of the currently recognised extant genera of non-geniculate coralline red algae, with the order Corallinales best represented. Nearly one in four species are endemic to the South African coastline and nearly one in three species are endemic to the region. Recent molecular evidence has pointed to a large number of cryptic species, suggesting that the true diversity for South Africa is substantially greater than what is currently recognised based solely on morphology and anatomy. [ABSTRACT FROM AUTHOR]

Knowledge and understanding of wetland vegetation is an important component of sound wetland ecosystem management as vegetation represents a link between biota and ecosystem processes. In this paper, the saline wetlands of the arid inland regions of South Africa are discussed. Even though these wetlands contain water only occasionally they are among the largest wetland ecosystems in the country and their ecosystem processes are mostly determined by hydrological processes and particularly clay and salt deposition. These wetlands are dominated by three different groups of plants: salt-tolerant lawn grasses, sedges (occasionally) or halophytic shrubs. A subset of data from the South African National Wetland Vegetation Database, representing these vegetation types was used for analysis by means of clustering and ordination techniques. Twenty-nine saline wetland communities are described and these are further summarized into 15 community groups. Of the environmental variables used to explain the variation in the vegetation patterns, wetness appears to have the most important effect as it is also negatively correlated with electrical conductivity. Among the cations, it is sodium that has the greatest influence on species composition. Most of the types of saline wetlands are restricted to the Northern Cape and Free State Provinces, but plots with salt-tolerant grasses are found in all provinces except Gauteng. [ABSTRACT FROM AUTHOR]

This paper describes grass lawn wetlands, which are wetlands subjected to dynamic conditions, particularly highly fluctuating water tables that regularly drop deep below the ground surface. This occurs mostly in floodplain wetlands, as well as in wetlands in semi-arid regions or coastal plains. These wetlands are often dominated by short lawn grasses, particularly Cynodon dactylon , while other life forms, from taller tufted sedges to trees and shrubs, occur less frequently. A subset of data from a nationwide survey of wetland vegetation representing these grass lawn wetlands was selected for analysis using clustering and ordination techniques. Thirty-seven wetland communities are described and are further summarized into 13 community groups. Wetland communities on the coastal plains were associated with sandy soils whereas most of the other communities had a high clay fraction. Grass lawn wetlands are commonly found in a zone along the central, semi-arid part of the country and for this reason will likely play an important role in wetland monitoring in the long term. [ABSTRACT FROM AUTHOR]

In this paper, the wetland vegetation types of subtropical wetlands occurring in South Africa are discussed. The South African National Wetland Vegetation Database targeted the collation of all available wetland vegetation data consisting of species composition, Braun-Blanquet cover-abundance data and the relevant environmental parameters. A subset of this database that represented subtropical wetlands, was used for analysis by means of clustering and ordination techniques. Forty-nine wetland communities are described and these are summarized into sixteen community groups. The most important factors that account for the variation among these wetlands are the soil clay percentage and associated soil electrical conductivity. Some communities are associated with peaty or sandy soils with a very low soil electrical conductivity on the coastal plain while others that occur more in loamy soils with a high soil electrical conductivity are associated with drainage channels, at the foothills of mountains or the escarpment. A specific group of wetlands is associated with nutrient-poor substrates of the Msikaba group Sandstones in Pondoland or on coastal sands of Maputaland. Subtropical wetlands are particularly vulnerable to degradation due to cultivation as they are found in some of the most densely inhabited rural areas of South Africa. [ABSTRACT FROM AUTHOR]

This paper aims to characterise and describe the species composition of serpentine sites of the Barberton Greenstone Belt as compared to surrounding non-serpentine areas. A floristic analysis of seven serpentine (serpentinite) outcrops of the Barberton Greenstone Belt, in the eastern part of South Africa, recorded 744 species and subspecies, 319 genera and 94 families. 18 taxa remain undescribed. The Barberton Greenstone Belt flora includes 32 taxa endemic to serpentine soils and six taxa considered to be hyperaccumulators of nickel. The taxa considered to be endemic to serpentine outcrops make up 39% of the number of endemics found within the Barberton Centre of Endemism. The serpentine vegetation is characterised by fewer trees than the surrounding vegetation and the dominance of grass species such as Themeda triandra , Heteropogon contortus and Loudetia simplex . The species composition of each outcrop is relatively unique with only about 30% of species shared between any pair of outcrops. The flora of the serpentine outcrops of the Barberton Greenstone Belt is found to be different to the surrounding non-serpentine vegetation in terms of number of species per family, the ratios of dicotyledons to monocotyledons and familial composition. [ABSTRACT FROM AUTHOR]