High Drakensberg Research Articles

Past Niche Tourism: The First Chapter of Mountain Tourism in South Africa

Mountain tourism enjoys a long history in many countries, much of which is unrecorded. This paper addresses one dimension of the neglected past of recreation and tourism in the Global South. The focus is on the development of mountain tourism as a form of niche tourism in South Africa. The paper contributes to the limited international historical scholarship on niche tourism. In addition, it extends the literature in South African tourism scholarship on tourism’s past, tourism history and the historical geographies of tourism. Using the limited extant literature and with primary archival sources the early development of mountain tourism in South Africa is investigated. The time period covered is from the mid-19th century to the early 1950s. Arguably, the initial origins of mountain tourism in South Africa must be situated at Table Mountain in Cape Town. The focus shifts subsequently to the growth of mountain tourism in the high Drakensberg range. Although mountain tourism is dominated by domestic visitors it is argued that the South African Railways played a vital role in exposing South Africa — and especially the Drakensberg — as a potential destination for international mountain tourists.

Late glacial (17,060-13,400 cal yr BP) sedimentary and paleoenvironmental evolution of the Sekhokong Range (Drakensberg), southern Africa.

Southern Africa sits at the junction of tropical and temperate systems, leading to the formation of seasonal precipitation zones. Understanding late Quaternary paleoclimatic change in this vulnerable region is hampered by a lack of available, reliably-dated records. Here we present a sequence from a well-stratified sedimentary infill occupying a lower slope basin which covers 17,060 to 13,400 cal yr BP with the aim to reconstruct paleoclimatic variability in the high Drakensberg during the Late Glacial. We use a combination of pollen, total organic carbon and nitrogen, δ13C, Fourier transform infrared spectroscopy attenuated total reflectance (FTIR-ATR) spectral and elemental data on contiguous samples with high temporal resolution (10 to 80 years per sample). Our data support a relatively humid environment with considerable cold season precipitation during what might have been the final stage of niche-glaciation on the adjoining southern aspects around 17,000 cal yr BP. Then, after an initial warmer and drier period starting ~15,600 cal yr BP, we identify a return to colder and drier conditions with more winter precipitation starting ~14,380 cal yr BP, which represents the first local evidence for the Antarctic Cold Reversal (ACR) in this region. On decadal to centennial timescales, the Late Glacial period was one marked by considerable climatic fluctuation and bi-directional environmental change, which has not been identified in previous studies for this region. Our study shows complex changes in both moisture and thermal conditions providing a more nuanced picture of the Late Glacial for the high Drakensburg.

Periglacial landforms in the high Drakensberg, Southern Africa: morphogenetic associations with rock weathering rinds and shrub growth patterns

ABSTRACT Here, we aim to establish possible morphogenetic associations between periglacial phenomena (sorted circles and turf-/stone-banked lobes) by examining (a) rock surface weathering rinds by thin section microscopy and SEM-EDX analysis, and (b) alpine shrub growth patterns of Helichrysum trilineatum supported by AMS 14C age determination. The study area is the Mafadi–Njesuthi summit zone, one of the highest alpine regions of southern Africa. Rock weathering results indicate that clasts in large sorted circle centres experience high chemical weathering rates on both exposed (upper) and non-exposed (lower) surfaces, whereas clasts in lobes and very large apparently ‘relict’ sorted circles have been inactive for a prolonged period of time, based on strongly contrasting weathering rates on both exposed and non-exposed clast surfaces. Large sorted circles originating from a previous (possibly Last Glacial Maximum or late-glacial) colder period are still marginally or episodically active, thus restricting plant succession on these landforms. Even where very large sorted circles and turf-/stone-banked lobes are inactive, their legacy continues, as expressed in today’s surface morphology, and still influence ground abiotic conditions through the generation of microrelief and microclimate which in turn have impacts on ecosystem patterns including the distribution of H. trilineatum. Such shrub growth patterns are influenced by microscale site morphology, associated abiotic controls, and ongoing seasonal cryogenic activity. Both active and inactive periglacial landforms on highest summits of the Drakensberg represent microscale environments with distinct fine-scale abiotic and geomorphic settings, which in turn are manifested through differences in plant ecology and rock surface weathering, respectively.

Fine-Scale Variations of Near-Surface-Temperature Lapse Rates in the High Drakensberg Escarpment, South Africa: Environmental Implications

The objective of this study is to determine fine-scale spatial and temporal trends in screen temperature, lapse rates, and inversions associated with the Great African Escarpment wall. Particular attention is focused on the characteristics of near-surface-temperature lapse rates, their variability associated with particular synoptic conditions, and environmental implications such as for modeling climate projections in topographic- and climatic-specific high mountain regions. Hourly temperature data were logged on northeast- and southeast-facing slopes over 12 months in 2001, in the high Drakensberg Escarpment of southern Africa, at a range of elevations including: 2650, 2900, and 3200 m a.s.l. High spatial and temporal variations in lapse rates are recorded and illustrated. A relatively low mean annual lapse rate of -0.42 °C 100 m-1 between 2650 and 2900 m a.s.l. doubles to - 0.84 °C 100 m-1 between 2900 and 3200 m a.s.l. The frequent westerlies and tropical temperate troughs provide for high lapse rates (-0.91 °C 100 m-1), which are likely responsible for the relatively high annual average lapse rate of -0.63 °C 100 m-1. Quantifying the fine-scale temperature trends has important implications for better understanding site-specific paleoenvironmental signatures and for projecting future climate scenarios and associated bio- and geosystem responses.

Lightning as a geomorphic agent on mountain summits: Evidence from southern Africa

The presence of angular bedrock-derived debris on mountain summits worldwide has usually been associated with present or past periglacial frost shattering, thermal fracturing and other climatically-mediated weathering processes. Climatic inferences are commonly made based on such geomorphological evidence, even if frost shattering and other processes are unlikely under present climatic conditions. This paper questions this assumed genetic link between present/past climate and production of angular bedrock-derived debris by describing the geomorphological impacts of lightning strikes on exposed mountain summits. Using examples from the high Drakensberg of eastern Lesotho, southern Africa, the impacts of lightning strikes are described, which include the generation of angular, fractured bedrock-derived debris. These impacts are identified in the field based on clear and unambiguous criteria that can be used to distinguish between lightning-induced weathering processes and those processes associated with ‘more typical’ alpine weathering. This paper argues that lightning strikes are an important geomorphic agent of, in particular, low-latitude mountain summits, and that to make uncritical climatic inferences based on the presence of ‘frost shattered debris’ on mountain summits is wholly erroneous.

Sand ramps in the Golden Gate Highlands National Park, South Africa: Evidence of periglacial aeolian activity during the last glacial

Sand ramps have been identified in a side-valley on the southern side of the Little Caledon River in the Golden Gate Highlands National Park, Free State, South Africa. The site lies in the foothills of the northern Drakensberg (Maluti) Mountains, and this study aims to explore the potential of such deposits to add to the sparse palaeoenvironmental record of the region. Up to 11 m of aeolian sand, banked against north-facing slopes, is exposed by fluvial incision through the deposits, revealing interbedded fluvial lenses and palaeosols. The region is currently devoid of significant aeolian sediment transport or deposition, and supports well-developed grassland vegetation; these deposits testify to former conditions different from those of today, which would have been characterised by depleted vegetation and a different wind and/or climatic regime. Biogenic proxies are absent from the deposits, but Optically-Stimulated Luminescence (OSL) dating of the sediments reveals that they accumulated at intervals throughout much of the last glacial event, from around 45 to 16 ka. These dates are consistent with those of vegetation changes from palaeoecological sites elsewhere in the region, and also with dated evidence for niche glaciation further south in the high Drakensberg. Evidence from this study supports significant landscape changes in the Drakensberg during the last glacial, with the foothills in the region of Golden Gate Highlands National Park subject to aeolian processes under a periglacial environment.

Alpine turf exfoliation pans in Lesotho, southern Africa: Climate–process–morphological linkages

Although alpine pans have been reported from a variety of mountain regions, these have received limited research attention and are thus amongst the least known of ‘closed basins’. This study investigates macro- and fine-scale morphological attributes and the process dynamics of alpine turf exfoliation pans in the high Drakensberg of Lesotho, southern Africa. Climate data (temperature, precipitation and wind) are used to better ascertain climate–surface process linkages and how these may be associated with the observed morphological phenomena. Thirty pans were assessed for both macro- and fine-scale aspect-controlled morphological attributes. During 2005, Tinytag™ temperature loggers recorded ground temperatures on various pan riser aspects to establish the potential for cryogenic activity. Similarly, wind speed and direction data from 2001 were used to identify the potential role of wind as an erosion and transportation mechanism. The number and total weight of detached turf clumps accumulated at the base of various pan riser aspects were determined in July 1999, September 2001 and September 2004. It is suggested that the pans originated through initial turf disruption by animal trampling and turf burning, followed by the cryogenic up-heave of sediments. The pans typically elongate towards the southeast as they enlarge, demonstrate most active erosion on eastern and southeastern riser aspects, and host seasonal micro-echo and micro-climbing dunes along such riser aspects. It is concluded that an annual cyclic (seasonal) pattern of contemporary climate-driven geomorphic processes, dominated by strong northwesterly winds, control the fine-scale morphological evolution of alpine turf exfoliation pans in the Lesotho highlands.

Spatial associations between longest‐lasting winter snow cover and cold region landforms in the high drakensberg, southern africa

.Although snow is known to influence landform genesis and distribution, the spatial associations between snow and landforms within particular cold regions has received limited research attention. We present a case study from the high Drakensberg of southern Africa, comparing the contemporary spatial pattern of longest‐lasting cold‐season snow patches with the distribution patterns of active and relic cold region landforms. Two 30 m resolution sets of TM images dated 3 and 19 August 1990 and a DEM were used to demonstrate the geographic trends of snow patch depletion during late winter. Geomorphological phenomena with known coordinates were then incorporated into the GIS. The spatial distribution of several periglacial land‐forms (earth hummocks, stone‐/turf‐banked lobes, block deposits, large sorted patterned ground) coincides with topographic positions that limit snow accumulation. However, the strong spatial association between longest‐lasting snow patches and palaeo‐moraines implies substantial snow accumulation at some high altitude south‐facing sites during the last glacial cycle.

Late quaternary moraines along the sekhokong range, eastern lesotho: contrasting the geomorphic history of north‐ and south‐facing slopes

.Considerable Quaternary environmental reconstruction for the high Drakensberg is based on geomorphological and sedimentological work undertaken along the northern aspects of the Sekhokong mountain range of eastern Lesotho. Given that no previous investigations have focused on the southern aspects, this paper documents the observed geomorphology and provides a more complete palaeo‐environmental picture for this range. Data on the morphology, sedimentology and micromorphology for two linear debris ridges are presented. It is demonstrated that the two ridges are most likely moraines originating from a small niche glacier. The combined use of macro‐ and micro‐scale sedimentology is proven to be an essential tool in ascribing a glacial process origin for the landforms, given the complex depositional history they have undergone. AMS ages obtained from the deposits (14 700 cal. yrs bp and 19 350 cal. yrs bp) places these in the time‐scale of the Last Glacial Maximum. The study demonstrates rather contrasting aspect‐controlled palaegeomorphological environments along the Sekhokong range, which is also reflected in the dissimilar contemporary biophysical micro‐environments. It is suggested that the south‐facing slopes were dominated by glacial processes during the Last Glacial Maximum (LGM), as is evident from the moraines, while the proposition for previously described north‐facing glacial cirques is rejected based on the absence of erosional/depositional evidence and greater insolation received on these warmerequator‐facing slopes. Rather, we propose that the observed north‐facing hollows are a product of a multitude of geomorphic processes spanning several tens to hundreds of thousands of years.

Recognition and palaeoclimatic implications of late Quaternary niche glaciation in eastern Lesotho

AbstractGeomorphic evidence of former glaciation in the high Drakensberg of southern Africa has proven controversial, with conflicting glacial and non‐glacial interpretations suggested for many landforms. This paper presents new geomorphological, sedimentological and micromorphological data, and glacier mass‐balance modelling for a site in the Leqooa Valley, eastern Lesotho, preserving what are considered to be moraines of a former niche glacier that existed during the Last Glacial Maximum (LGM). The geomorphology and macro‐sedimentology of the deposits display characteristics of both active and passive transport by glacial processes. However, micromorphological analyses indicate a more complex history of glacial deposition and subsequent reworking by mass movement processes. The application of a glacier reconstruction technique to determine whether this site could have supported a glacier indicates a reconstructed glacier equilibrium line altitude (ELA) of 3136 m a.s.l. and palaeoglacier mass balance characteristics comparable with modern analogues, reflecting viable, if marginal glaciation. Radiocarbon dates obtained from organic sediment within the moraines indicate that these are of LGM age. The reconstructed palaeoclimatic conditions during the LGM suggest that snow accumulation in the Drakensberg was significantly higher than considered by other studies, and has substantial relevance for tuning regional climate models for southern Africa during the last glacial cycle. Copyright © 2009 John Wiley & Sons, Ltd.

Rock‐surface temperatures of basalt in the drakensberg alpine environment, lesotho

.Rock temperature data are presented for a variety of topographic localities at a high Drakensberg site. The objective is to investigate the spatiotemporal variations of surface rock temperatures in high Drakensberg basalt. The temperature results are then used to discuss possible implications for thermal stress fatigue and frost‐induced weathering. Tinytalk™ data loggers and probes were used for rock‐surface temperature recording. Long‐term measurements were recorded over 12 months from May 2002 to April 2003, at a 1‐hour logging interval and rock depth of 1 cm for a highaltitude (3300 m a.s.l.) interfluve and fracture site. Whilst the north‐facing rock surface experiences negligible hours below −3°C, the south‐facing rock surface and interfluve sites are subjected to considerable periods below −3°C, which falls within the ‘frost cracking window’. It is concluded that the substantial contrasts of recorded rock thermal parameters over small spatial scales between various topographic settings, highlight that site‐specific measurements across the broader scale are required for an adequate evaluation of regional weathering and its associated landform development.

A Synoptic Review of the African Genus Hesperantha (Iridaceae: Crocoideae)

Although revised in the past 20 years for the two major centers of its range, the southern African winter-rainfall zone and the eastern southern African Drakensberg, the sub-Saharan African genus Hesperantha remains inadequately understood. Continuing botanical exploration in southern Africa has resulted in the discovery of several new species and of populations of species known only from the type or very few collections. Species are listed here in a revised taxonomic order together with keys for the genus in the southern African winter-rainfall zone and in eastern southern Africa and tropical Africa that have a summer-rainfall climate. Included here are 11 new species, a shift in the application of the name H. candida to plants called H. vernalis, recognition of H. leucantha for plants previously called H. candida, and a series of novel observations relating to species delimitation, biology, geography, and taxonomy. Important range extensions are also noted for poorly known species, among them H. ciliolata, H. flava, H. quadrangula, and H. teretifolia. Including the novelties described in this account, 79 species of Hesperantha are now recognized, 4 in tropical Africa, 37 in summer-rainfall southern Africa, mostly of the Drakensberg, and 42 in winter-rainfall southern Africa. Hesperantha longicollis and H. coccinea are shared between tropical and eastern southern Africa, and H. rediote and H. bachmannii between the winter- and summer-rainfall zones of southern Africa. The new species from the southern African winter-rainfall zone are: H. decipiens, from Narnaqualand, allied to H. radiata; H. glabrescens, from the Roggeveld Escarpment, closely related to H. pilosa; H. malvina, also related to H. pilosa, from cliffs on the Anysberg in the Little Karoo; H. rupicola, a lithophyle from western Bushmanland, possibly most closely related to H. acuta; and H. sufflava, a member of section Hesperantha from Malmesbury in Western Cape Province. New species from the southern African summer-rainfall zone are: H. altimontana, a spring-blooming, white-flowered species of the high Drakensberg of Lesotho and KwaZulu-Natal; H. brevistyla, a dwarf plant from Free State and adjacent KwaZulu-Natal; H. debilis, evidently allied to the widespread H. bachmannii, from the Albany Distriet of Eastern Cape Province; H. exiliflora, from Lesotho, which has small, purple flowers; H. saxicola, of rocky outcrops in Mpumalanga, South Africa, which has large white flowers with short anthers; and H. stenosiphon, a long-tubed, pink-flowered species with blackish anthers from Eastern Cape, South Africa.

A note on needle‐ice mound formation in the High Drakensberg, Southern Africa

AbstractSmall needle‐ice mounds are described from the High Drakensberg. They develop infrequently during periods of several days of uninterrupted cold conditions. Ice growth incorporates sediment and stones. An accumulated segregated ice length of >41 cm was measured, with clasts heaved ∼14 cm. During subsequent thaw phases, the ice ablates from the top downwards, forming sediment veneers and cappings. These mounds contribute towards turf exfoliation, thereby exposing sediment to deflation. Copyright © 2002 John Wiley & Sons, Ltd.

Turf exfoliation in the high drakensberg, southern africa

Limited research attention has focussed on turf exfoliation as a denudation process in mountain environments. This paper examines some characteristics of turf exfoliation forms identified within particular valley zones in the Drakensberg alpine belt. Morphological and sedimentological data are presented for turf exfoliated sites investigated in the Mashai Valley of eastern Lesotho. It is found that a variety of processes, including needle ice action, biological activity, fluvial processes and deflation, operating synergistically, are responsible for contemporary turf exfoliation in the high Drakensberg. It is apparent that the strong seasonality from mild, wet summers to cold, dry winters has helped induce the annual cycle of dominating processes.

Needle ice observations from the high Drakensberg, Lesotho

AbstractNear‐surface ground thermal conditions are a delayed response to changing air temperature and may result in needle ice development when air temperatures are above 0 °C and ground temperatures below 0 °C. It is difficult, therefore, to predict needle ice development based only on climatological data. Observations indicate that temporally restricted growth phases produce shorter needle ice lengths than longer growth phases. Copyright © 2001 John Wiley & Sons, Ltd.RÉSUMÉLes conditions thermiques proches de la surface du sol évoluent avec retard après un changement de la température de l'air, aussi des pipkrakes peuvent se développer quand la température de l'air est supérieure à 0 °C et que la température du sol est inférieure à 0 °C. Il est difficile, en conséquence, de prédire le développement des pipkrakes d'après les seules données climatologiques. Des observations indiquent que de courtes phases de croissance produisent des pipkrakes de longueur plus réduite que des phases de croissance de plus grande durée. Copyright © 2001 John Wiley & Sons, Ltd.

Stone-banked lobes and environmental implications, high Drakensberg, southern Africa

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Block and debris deposits in the high drakensberg, lesotho, southern africa: implications for high altitude slope processes

Past evaluation of high altitude slope development in Lesotho, southern Africa, is largely based on hypothetical or macro‐scale geomorphic approaches. Consequently, the information pertaining to high altitude southern African Quaternary slope environments has remained rather rudimentary. The present study describes the morphology and discusses the likely palaeogeomorphic processes of blockstreams and debris deposits on the Popple Peak and Njesuthi‐Mafadi south‐facing‐slopes in the Drakensberg. The geomorphic evidence provides much needed information to help improve the understanding of south‐facing slope processes during past colder periods. A model for high altitude Drakensberg south facing slopes is presented and used to challenge and expand on recent models and ideas on southern African valley asymmetry. It is found that solifluction and debris flows/avalanches were operative on south‐facing slopes during past cold periods and thereby contributed to past slope development at some high altitude sites in Lesotho. However, the geomorphological observations do not support the valley asymmetry hypothesis and it is suggested that greater caution be exercised in valley‐form interpretations, particularly where geomorphological ground‐truthing has been absent.

Non-Sorted Patterned Ground in the High Drakensberg, Southern Africa: Some New Data

This paper presents empirical data on non-sorted patterned ground in the high Drakensberg. Some morphological and sedimentary characteristics for thufur and nonsorted steps are provided. The study also examines process data on ground heave activity at a thufur site. Contemporary cryogenic activity at the non-sorted steps is indicative that the patterns are at least seasonally active. Soil heave measurements at the Mashai Valley thufur site support the contention that some thufur are active in the high Drakensberg.

Annually re-forming miniature sorted patterned ground in the high Drakensberg, southern Africa

An analysis of miniature sorted circles and polygons provides the first detailed assessment of sorted patterned ground from a southern African alpine region. Pattern dimensions and particle sorting were determined from two sites in the high Drakensberg. Although the sorted patterns in the high Drakensberg are somewhat polygenetic in developmental origin, they are primarily frost-induced. Miniature sorted patterned ground below 3200 m a.s.l. on the Drakensberg plateau develops annually during the winter months and disintegrates towards summer. The development of miniature sorted patterns within five to six weeks demonstrates the effect of regular freeze–thaw cycles at higher altitudes in the Drakensberg. © 1997 by John Wiley & Sons, Ltd.

A NOTE ON THE MORPHOLOGY OF MINIATURE SORTED STRIPES AT MAFADI SUMMIT, HIGH DRAKENSBERG

ABSTRACT The dimensions and sorting characteristics of miniature sorted stripes at Mafadi summit in the high Drakensberg are determined. Water induced mechanisms, wind action, anthropogenic factors, frost heave and thermal creep are considered as possible contributing factors responsible for contemporary particle movement and stripe formation on the Mafadi slopes. The sorted stripes are frost-induced landforms which are degrading under present environmental conditions. It is suggested that the pronounced altitudinal climatic cooling at higher Lesotho summits has prevented vegetation establishment but enabled the preservation of cold-region landforms.