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Item Open Access 3D Cranial Morphometry, Sensory Ecology and Climate Change in African Rodents(2019-05-15) Nengovhela, Aluwani; Taylor,, Peter; Braga, JoseThe order Rodentia is the most speciose group of mammals with muroids being the most diverse superfamily. Since they are represented in arboreal, semiaquatic, subterranean and terrestrial niches, rodents may exhibit morphological traits reflecting their adaptations to such diverse environments. This thesis focuses on the morphology of the endocranium, auditory bulla and cochlea in three tribes (Otomyini, Taterillini and Gerbillini) representing 10 species of African rodents, concentrating on their variability, function and adaptability, using micro-CT imaging and 3D shape comparative methods. Additionally, variations in cranial size were also studied in respective of global warming and climatic variables. Morphological changes/variations are a result of environmental change, therefore each chapter in this study details the effect of environmental change (in space and time) on different morphological traits i.e. general cranial size (chapter 2), cochlea and auditory bulla (chapter 3) and endocranial size and shape (chapter 4). With chapter 2 dealing specifically with climate change in its strict sense and the remaining two chapters looking at different environmental gradients. Chapter 2 tests the applicability of the “third universal response to warming” (i.e. declining body size) and the Resource Rule in two murid subfamilies, Murinae and Gerbillinae. The study shows that the third response is not as universal as only one species conformed to this response. Further, food availability (Resource Rule) was shown to be the more important factor correlated with body size variations in rodent species than Bergmann’s Rule. Chapter 3 looks at the auditory bulla and cochlea, the morphological traits that play a role in hearing capabilities of rodents. I found, with some exceptions, that bulla and cochlea modifications between species could be explained by environment, phylogeny and/or allometry. In addition, I concluded that true desert adapted laminate-toothed rats and gerbils use both bulla and associated cochlea hypertrophy. Chapter 4 shows larger brain size in Taterillini and two species of Otomyini, with life histories and environment being the most probably factors responsible for xiv this. Using a novel method of diffeomorphism (deformation models), there was more variation in endocranial morphology between the gerbils and laminate-toothed rats than within them with olfactory bulb, paraflocculi, and posterior ventral cortex showing the most variability. Overall, this thesis shows that variations in the morphological traits studied are strongly influenced by the environment and function.Item Embargo An analysis of exposure and slope gradient impact on tree layer profile of Maroelakop vegetation in Nylsvley Nature Reserve, Limpopo Province, South Africa(2024-09-06) Mavhila, Tendani; Tshisikhawe, M. P.; Magwede, K.Since the 1850s, plant ecologists have been eager to investigate challenges in vegetation communities that are related to slope. The aspect of the slope is crucial in terms of the diversity and distribution of plants. This research was conducted on Maroelakop Mountain within Nylsvley Nature Reserve located in Mookgopong, Limpopo Province. The investigation aimed to assess and contrast the vegetation composition on the north-facing slope with that of the south-facing slope. The specific goals included ascertaining the density and frequency of dominant tree species on each slope, calculating the importance value indices of trees on both slope gradients and analyzing the population structure of the slope gradient. Point Centred Quarter (PCQ) was used in data collection. Shannon-Weiner diversity index, Simpson diversity index, and Evenness index were used to measure plant species diversity. In this study, a total of 600 trees were discovered and identified by their botanical names. The data represented 21 plant species in 17 genera and 12 families. The tree layer of the north-facing slope was dominated by Diplorhynchus condylocarpon, whereas that on the south-facing slope was dominated by Burkea africana. Both tree species had high-importance value indices. Shannon diversity index of 2.20 was obtained for the North-facing downslope, whereas the South-facing downslope had 1.74. The average Simpson diversity index for the North-facing slope was 0.82 and South-facing slope 0.77. The average Evenness index for the North-facing slope was 0.93 and, on the South-facing slope 0.81. This study concluded that Diplorhynchus condylocarpon is the most prevalent species within Maroelakop Mountain in the Nylsvley Nature Reserve.Item Open Access Ant and spider diversity in a rural landscape of the Vhembe Biosphere, South Africa(2017-09-18) Mauda, Evans Vusani; Foord, S. H.; Munyai, T. C.See the attached abstract belowItem Open Access Assessing species richness patterns and conservation threats (due to overharvesting and climate change) in South African Cycads, with emphasis on a population of Encephalartos tranvenosus Stapf and Burt Davy from the Soutpansberg Mountain, Limpopo Province(2018-05-18) Bamigboye, Samuel Oloruntoba; Tshisikhawe, Peter Milingoni; Taylor, Peter JohnCycads are regarded as the oldest living seed plants on earth and they have existed for about 300 million years. Ever since the awareness of the existence of this plant group, they have been facing high extinction risk. Currently they are referred to as the most threatened plant group in the world. Many ecological and anthropological forces are promoting extinction crisis of this taxonomic group. Africa is one of the centres of diversity of this plant group with 70% of the total number of the taxa in this group in Africa found in South Africa. Also South Africa is one of the global hotspots for cycads and it contains the third largest number of cycads after Australia and Mexico. Studies have revealed that there have been high threats and extinction risks among the cycad taxa in South Africa. The Soutpansberg Mountain is a major biodiversity hotspot in Limpopo Province in South Africa with high level of flora and fauna taxa. About 3000 vascular plants species are represented on this mountain. Biodiversity on this mountain has been under threat in recent times and there is need to investigate how cycads are facing risk on this mountain. The main focus of this study is to look at the extinction pattern in South African cycads and cycads endemic to Soupandberg Mountain in Limpopo Province in South Africa. v The first objective evaluated all African cycads over a decade using IUCN red list. Data from IUCN 2014 version was used to calculate the percentages of African cycads in each IUCN categories. The results were compared with those presented by Donaldson 2003. They showed that there have been significant decline and increase in extinction of African cycads over this period. It was also discovered that majority of this extinction crisis were trending in South Africa. The second objective used the IUCN red list to evaluate extinction pattern in South African cycads. The percentages of IUCN threat categories of South African cycads was calculated using IUCN red list. ArcGIS was used to construct distribution map for threatened and extinct South African cycads. The study revealed that the proportion of historically Extinct and Critically Endangered cycads is higher in Limpopo, KwaZulu-Natal and Mpumalanga than the rest of the provinces in South Africa. The third objective of this research investigated extinction pattern of Encephalartos transvenosus Stapf & Burtt Davy (Modjadji cycad) on Soutpansberg Mountain. Indigenous knowledge and population ecology approaches were used to determine current threats Modjadji cycads are facing on Soutpansberg Mountain. The results showed that anthropogenic activities have caused a substantial decline of one important unprotected population of this species on Soutpansberg Mountain.Item Open Access Assessment of androstachys johnsonii prain, stem utilization in Matshena Village, Mutale Local Municipality, Limpopo Province(2016-02-02) Bakali, Mulalo; Tshisikhawe, M. P.; Ligavha-Mbelengwa, M. H.Item Embargo Assessment of nutraceutical attributes of selected wild edible fruit plants used by Vhavenda people of the Thulamela Local Municipality(2024-09-06) Nephawe, Rinae Lucy; Mokganya, M. G.; Madala, N. E.Wild edible fruit plants are highly valued in many remote rural areas, where they play a significant role in fulfilling the sociocultural and livelihood needs of people. Many of these plants are harvested by local communities to augment and diversify their diets as well as to promote local food security. The decline in the use of wild edible fruit plants may be due to a lack of knowledge of their nutritional value, their potential for income generation, and medicinal and cultural uses. This study focused on the documentation of utilisation, conservation, and nutraceutical composition of the wild edible fruit plants of the Thulamela Local Municipality. Information on wild edible fruit plants was gathered through semistructured interviews, fieldwork, and a literature review. A total of 39 wild edible fruit plants of 22 botanical families recorded during the study were used as food, beverage, and additionally as medicine. The number of wild edible fruit plants with medicinal properties was 39 whereas those used to make beverages were 9. Wild edible fruit plants of Thulamela municipality were experiencing challenges due to human activities resulting in declining, endangered, or even extinct. Results of this study also showed the use of wild edible fruit plants as firewood because 10 out of 39 were mentioned for this use. In this study the UHPLC-qTOF-MS/MS-based in source collision induced dissociation method was utilized to generate fragmentation data to assist in the differentiation of closely related isomers. Wild edible fruit plants have been used for centuries in traditional medicine and for nutritional purposes. Strychnos species has not yet been fully decoded, and due to the inherent complexity of plant metabolomes, the characterization of Strychnos photochemistry remains challenging. Thus, in this study, we propose the use of molecular networking to unravel the families using the metabolome analysis of two Strychnos species (Strychnos pungens and Strychnos spinosa) and highlight the relevance of molecular networking in exploring the chemotaxonomy of plants. This allows visualization of chemical classes and the variety of substructures within the molecular families.Item Open Access Bioactivity and chromatographic profiles of the selected medicinal plants against candida albicans(2015-07-17) Mulaudzi, Takalani Millicent; Masevhe, N. A; Mojapelo, P. E. LItem Embargo Compatible components of the integrated pest management of Bathycoelia distincta (Hemiptera: Pentatomidae(2024-09-06) Manzini, Shaun; Foord, S. H.; Joubert, E.Two-spotted stink bug, Bathycoelia distincta Distant (Hemiptera: Pentatomidae), is a major pest of macadamia. It causes damage by directly feeding on macadamia kernel throughout the season and reducing nut quality by inducing nut abscission, premature nut abortion, necrotic lesions, deformed kernels, discoloration, or translucent blemishes on the kernel. Currently, growers rely on chemical insecticides to control stink bug populations. However, with overreliance and extensive use of chemical insecticides, the B. distincta has developed some resistance to certain active ingredients Furthermore, there is no doubt that agricultural intensification is the primary driver of the loss of biodiversity globally. Therefore, there is a need to develop Integrated Pest Management (IPM) strategies to effectively minimize the damage caused by B. distincta and the loss of biodiversity due to agricultural intensification. The goal of this study was to investigate the role of landscape context, elevation, flying vertebrates, and pesticide application in shaping arboreal arthropod assemblages and macadamia nut quality metrics and evaluate the efficacy of alternative pest control measures to control B. distincta, explicitly focusing on entomopathogenic fungi and egg parasitoids Trissolcus basalis (Wollaston, 1858) (Hymenoptera: Platygastridae). Landscape context and elevation were the principal factors that explained species richness and arthropod size. Species richness and insect size decreased with increasing pesticide application rate; however, it was not significant. Insect damage did not vary in response to pesticide application, but the proportion of sound kernels decreased significantly with increasing pesticide application. All entomopathogenic fungal treatments were effective against B. distincta, with chitinase enzyme leading to a 95% mortality rate. Under field conditions, EPFs and a chemical knock-down spray showed no significant difference between the treatments. All parasitoid treatments significantly affected B. distincta egg mortality, with two pairs reaching a 100% parasitism rate. The processes that increase sound kernel recovery seem to be related to an increase in invertebrate community diversity and arthropod size, and although the mechanisms related to this are not always clear, the results suggest that arthropod diversity could be a good proxy for these processes. On the other hand, the study results showed that EPFs and stink bug egg parasitoids, Trissolcus basalis, may be used as biological control agents against B. distincta. Overall, the thesis emphasizes the importance of reducing pesticide application and using biological control agents, promoting more sustainable agricultural practices, and supporting biodiversity to improve ecosystem service provided by pest natural enemies.Item Open Access Conservation Strategies of the Red Listed Brackenridgea zanguebarica Oliv. in Vhembe District Municipality, Limpopo Province, South Africa(2019-09-20) Tiawoun, Makuete Andre; Tshisikhawe, M. P.; Gwata, E. T.Brackenridgea zanguebarica Oliv. (Ochnaceae) commonly known as “Yellow Peeling Plane”, is an important medicinal plant species, and one of the most threatened tree species that is endemic to Thengwe village in Vhembe District, South Africa. It is widely harvested for traditional purposes and difficult to propagate sexually and asexually. Nowadays, it has become threatened and this unique plant population is believed to be declining in the Brackenridgea Nature Reserve (BNR). According to the Red List of South African plants, B. zanguebarica is considered a critically endangered medicinal plant. All these facts combined with a lack of knowledge on the conservation of this species prompted this study on its conservation. To ascertain the effective conservation and proper management of this multipurpose tree, this study was conducted with the aim to improve its conservation strategy by investigating current threats to the existence of B. zangueberica, the chemical constituents from the different plant parts, the propagation methods of the species, and the factors delaying the germination of its seeds. In this study, an assessment of the current population threats was important as a first step in conservation; this would update the status of the species in its natural habitat. The current status of Brackenridgea zanguebarica was conducted through an extensive field survey in the Brackenridgea Nature Reserve (BNR), where a belt transect method was deployed to record quantitative information, while the harvesting damage was estimated using a sliding scale from 0 to 5. The structure of the populations in terms of the stem diameter size classes showed a bell shape vi pattern. About 60% of individuals showed some signs of plant parts extraction as the stem bark was reported to be the main plant part harvested. The population structure, however, was dominated by juvenile plants due to the selective harvesting of mature individuals; this hinders fruit production leading to poor or slow seed production. The present study aimed to compare the chemical constituents and the antimicrobial activities of some parts of this plant species. The extracts were screened for phytochemicals using standard methods. Thin-layer chromatography (TLC) was carried out to compare the chemical constituents using various solvent systems of varying polarity. Agar well diffusion and broth microdilution methods were used to evaluate the antimicrobial activity and the minimum inhibitory concentrations (MIC) of plant extracts respectively, against three bacteria and four fungi. The phytochemical analysis revealed a close similarity of various phytoconstituents of the three plant parts (stem bark, twigs and leaves). TLC analysis showed a slight difference in the acetone extract of different plant parts with more bands on the leaves than the stem bark and twigs. Acetone extracts of the three plant parts exhibited varying degrees of antimicrobial activity against Staphylococcus aureus and Candida glabrata, while none of the extracts showed any activity against Escherichia coli, Klebsiella pneumonia, Candida albicans, C. krusei, and C. parapsilosis. However, analysis of the antibacterial activity of various extracts revealed that the best inhibitory activity was produced by the stem bark extract compared to the leaf and twig extract. vii The sustainable way to meet the growing demand of Brackenridgea zanguebarica is to increase its availability through propagation practices. Unfortunately, the conservation of B. zanguebarica is hampered by lack of information on how it can be propagated. Sexual and asexual propagations were conducted to determine an efficient method to increase the number of individuals of this plant species. Seed propagation was carried out to study the effect of various pre-treatments on germination, in order to understand the germination requirements; vegetative propagation was conducted to assess if B. zanguebarica could be successfully propagated via stem cuttings if the appropriate growth hormones and growing media were applied. Brackenridgea zanguebarica seed did not germinate at all under any of the conditions tested. However, the results, showed the potential of propagating this species from stem cutting despite the poor results obtained. Thus B. zanguebarica was found to be difficult to propagate sexually and asexually. Seeds serve as a means of reproduction and a vital element to ensure the survival of plant species. Seed germination is controlled by a number of factors. The propagation of B. zanguebarica via seed is very difficult and research has not been undertaken to understand possible factors that may delay its germination. This study was aimed to investigate and describe both the morphological and anatomical features of B. zanguebarica seed, in order to identify structural features implicated in its poor germination. To achieve this goal, a morphological and anatomical study was conducted based on the observation of seeds under a scanning electron microscope (SEM) and light microscopy (LM). Water uptake potential was assessed by the increase in seed mass. The morpho-anatomical analysis indicated that some structures of the seed, such as seed coat, and the presence of endosperm viii surrounding the embryo that consisted of two prominent cotyledons, seem to greatly hinder the germination of this species. The research findings provided information regarding the seed structure which is one important step in identifying useful techniques to improve seed germination for conservation purposes.Item Open Access The distribution patterns, utilisation and conservation of Sclerocarya birrea (A. RICH.) HOCHST, SUBSP. CAFFRA in two villages of the Limpopo Province, South Africa(2016-05) Mocheki, Tebogo Allison; Ligavha- Mbelengwa, M. H.; Tshisikhawe, M. P.See the attached abstract belowItem Open Access Distribution, population status and conservation of the samango monkey (Cercopithecus albogularis schwarzi) in the Limpopo Province, South Africa(2020-02) Linden, Birthe; Taylor, Peter J.; Dalton, Desire L.A general introduction about the need for studying forest dwelling primate populations in fragmented landscapes and more specifically in the Soutpansberg is given in Chapter 1. Forests affected by fragmentation are at risk of losing primate populations over the long term. In addition, although the impact of fragmentation on primate populations has been studied in many places in Africa, Asia and South America there is no consensus of how the different primate species react to forest disturbance and fragmentation. This study aims to investigate the impacts of natural and anthropogenic forest fragmentation on the Soutpansberg samango monkey population including their distribution, genetics, and phylogeography, identifying threats and mitigation measures. To date, no detailed population level research has been undertaken on samango monkey populations in the far north of their South African distribution. By collecting a diverse data set, in addition to existing ecological data, this study generates conservation and management recommendations suited specifically to the study area and the study species and provides baseline data for future monitoring. Chapter 2 details how through creating an accurate forest distribution map and collecting samango monkey distribution records through surveys we were able to investigate how both natural and anthropogenic forest fragmentation influences the distribution of samango monkeys in the Soutpansberg. We explored forest patch occupancy and connectivity, determined the degree and nature of matrix utilisation and identified possible threats to forests and samango monkeys between the contrasting landscapes of the eastern and western Soutpansberg. Here we found that samango monkeys largely occupied forest patches <100 ha in size and that the Soutpansberg has very few forest patches > 100 ha available. We showed that samango monkeys used all components of the surrounding matrix and that lone or bachelor group males used the matrix more extensively than groups. We found that paved roads pose a major threat, however not a barrier, to samango monkey populations when navigating the matrix. Forest connectivity was found to be influenced by the distance between patches and possible corridors or stepping stones of isolated forest patches connecting them. Patterns found in this chapter contrasted between the eastern and western landscapes requiring different adaptive strategies from the samango monkeys and different conservation approaches from practitioners. In this chapter we conclude that samango monkeys, having evolved in fragmented landscapes, are comparatively tolerant and adaptable to a human- transformed matrix. In Chapter 3 we focused on the effects that natural and anthropogenic habitat fragmentation in the Soutpansberg has on the genetic diversity and structure of the samango monkey population in the mountain range. Here we used microsatellite and mitochondrial DNA data from faecal and tissue samples collected from four local samango monkey populations across the Soutpansberg. We also included samples from an outlying population on the escarpment south of the mountain, the most likely historical migration route into the Soutpansberg. Our analyses showed that the Soutpansberg population is divided across the mountain and that genetic diversity within the Soutpansberg decreases with increasing distance to the escarpment population and from east to west. We found a lack of contemporary gene flow suggesting that the Soutpansberg population is completely isolated from the closest source population in the escarpment and that populations within the mountain range are isolated from each other. Based on our results we suggest that extensive anthropogenic changes to the landscape in the eastern Soutpansberg and distance between high canopy forest patches in the western Soutpansberg appear to have reduced the ability of samango monkeys to disperse between sampling areas. Overall, we found that natural and anthropogenic fragmentation and geographical distance are potential drivers for the observed population genetic differentiation and that the matrix surrounding forests and its suitability for samango utilisation plays a role at the local scale. In this chapter we conclude that the degree of samango monkey population subdivision and the apparent lack of contemporary migration between populations raises concerns about the long-term viability of populations across the mountain range. Having identified road fatalities as the main direct anthropogenic threat samango monkeys are exposed to when utilizing the matrix, we further investigated this issue in more detail in Chapter 4. Here we aimed to get a better understanding of where roadkills most likely occur and how to mitigate these through using suitable canopy overpasses. As road fatalities threaten primate populations globally, we used the samango monkey (Cercopithecus albogularis) as a model species to test the suitability of two different canopy bridge designs through field experimentation and behavioural data collection for arboreal guenon roadkill mitigation. Analysis of actual roadkill data collected in the study area provided insights into the nature of high-risk localities. We showed that canopy overpasses are a viable intervention for mitigating arboreal guenon road fatalities, reducing the probability that monkeys will cross a road on the ground. Samango monkeys clearly preferred a pole bridge over a rope ladder design and canopy bridges were preferred to trees and the ground when the tree canopy was open. Pole bridges were also used by other non-guenon primates and non-primate species. We showed that although samango road kills were not predictable in time (no seasonality), adult female and immature fatalities were predictable in space, restricted to bisected riparian zones and roads close to intact forests. We further found that adult male road fatalities can be expected in seemingly unsuitable habitat areas. This chapter highlights the importance of the correct interpretation of spatial, temporal and demographic data on road fatalities and how experimental research prior to installing crossing structures could increase mitigation impact. In Chapter 5 we investigate the regional phylogeography of samango monkeys, providing a deeper understanding into their evolutionary history in repeatedly fragmented forest habitat due to paleoclimatic fluctuations. Here we used mtDNA and microsatellite data obtained from tissue samples from a coastal population (Vamizi Island) in Mozambique and compared this to existing data from South Africa. The additional analysis of Mozambique animals allowed us to further test the number and timing of radiation events of Cercopithecus monkeys in southern Africa. In this chapter we propose the occurrence of a single, north-south radiation event during the midPleistocene along the Afromontane forest belt and that after the Last Glacial Maximum, samango populations re-radiated into (re)established coastal forests on a more local scale. Taking the findings from all chapters together we provide overall conclusions and conservation and management recommendations in Chapter 6. Here we also include interview data to give insights into public perceptions of samango monkeys and possible human-primate conflicts as we consider this an important aspect of conservation planning. In this final chapter we conclude that although samango monkeys appear comparatively adaptable to changes in the matrix surrounding their forest habitat, direct threats and forest patch isolation by distance may pose risks to populations in future. We advocate that conservation and management strategies aimed at the longterm persistence of the samango monkey populations and their forest habitat across the Soutpansberg should be formulated separately for the eastern and western parts of the mountain range as differing landscape variables pose different threats to forest and samango monkeys, thus requiring separate conservation and management approaches. We further recommend explicit mention of distinct management requirements for maternal groups and lone or bachelor group males to achieve a holistic conservation approach for samango monkey populations on the landscape scale. Findings of our study are not only relevant for samango monkey populations in the Soutpansberg but also for populations elsewhere in South Africa and southern Africa generally where forests and samango monkeys share the same paleohistory and current anthropogenic threats.Item Open Access Documentation and nutritional evaluation of some wild edible fruit plants and traditional vegetable of the Vhembe District Municipality, Limpopo Province, South Africa(2019) Mokganya, Mokgaetji Georginah; Tshisikhawe, Milingoni Peter; Mushaphi, Lindelani FhumudzaniWild plants have been used since time immemorial by native people all over the world. In many sections of the rural areas, people traditionally harvest wide range of leafy vegetables, roots tubers and fruits from the wild because of their taste, cultural practices, as food supplements or to tide over food shortage. It has been reported that wild plants have been recognized to have potential that satisfies the needs on household food and income security. Millions of people in many developing countries do not have adequate sources of food to meet their daily nutritional requirements and furthermore, many people are suffering from malnutrition due to lack of one or more micronutrients. Thus, in most situations, rural communities rely on wild resources including edible vegetables and fruits to meet their daily food requirements. Relatively little research projects conducted in the Vhembe District paid attention on wild edible plants and their nutrients. Therefore, the aim of this study was to further document wild edible plants and to evaluate nutritional status of some of these plants. To achieve this, an investigation was conducted in the four local municipalities of the Vhembe District municipality. Ten homesteads from four villages of each of the four local municipalities were randomly sampled to select respondents of this project. A total of 160 informants were interviewed through semi-structured questionnaires to firstly check the knowledge transfer from elderly members to youth members of Vhembe communities. This study demonstrated the major indigenous debility among the youth members who live in urban villages. Secondly, information concerning other different use categories was gathered through interviews with the 160 informants. Documented use categories mentioned during the interviews include food, medicine, beverages, construction, firewood, cosmetic, dye and artifacts. Sclerocayra birrea had eight use categories as compared to other edible fruit plant species. The list of documented wild edible plants includes trees, herbs, creepers, climbers and shrubs. Leaves of the mentioned growth forms were mostly used as compared to plants parts such as fruits, rhizomes, tubers, seeds and flowers. Some of the plants were mentioned to be available during certain seasons, therefore they were preserved using the sun drying method. Some edible parts can either be collected and sun dried or collected, cooked and then sun dried. Micronutrients are essential for the normal growth of children; however, there is disturbing reports of low intake of micronutrients rich foods eaten by children residing in poor rural areas. Some reports showed the low intake of Vitamin A in black children younger than 10 years of ages. Vitamin A deficiency continues to be a major public health problem in South Africa; therefore, this study also evaluated Vitamin A and C statuses from selected vegetables. Plants that received attentioned were selected based on their frequency of use and availability. Leaves of Amaranthus thunbergii and Amaranthus hybridus had outstanding Vitamin C concentration of 69.106 mg/100g and 43.299 mg/100g respectively. Majority of the wild edible vegetables (i.e. six out of eight) evaluated contain substantial quantities of β-carotene. Exceptionally, leaves of Solanum retroflexum contained high level of 10.905 β-carotene. The study therefore recommends an urgent need for the documentation and promotions or awareness campaigns as a way of dealing with the loss of indigenous knowledge. Moreover, researches related to cultivation of wild edible plants must be considered. Nevertheless, despite the rich indigenous knowledge on the medicinal use of the wild plants which is well documented; more research particularly to serve the concern on socio-economic, pharmacological and nutritional aspects still require satisfactory attention.Item Open Access Does observational methods affect the observed impacts of exotic plants on flower visitors in around Macadamia orchards(2020-02-20) Ramotjiki, Mancha Lorraine; Foord, S. H.; Schoeman, C. S.Pollination of flowering plants is mostly facilitated by insects. However, there is a global decline in the pollination services caused by invasive alien plants (IAPs), excessive use of pesticides, habitat loss, and fragmentation. IAPs affect native plants pollinators and integrate into their network interactions. Habitat loss leads to small remnant patches surrounded by a matrix of mainly agricultural activities, these remnant patches support native vegetation and provide forage to pollinators within and outside the flowering period of agricultural crops. However, these patches are also vulnerable to invasion by IAP’s. Macadamia nuts are one of the fastest growing markets in South Africa. Macadamia nut trees (Macadamia integrifolia) are mostly pollinated by wild and managed honey bees (Apis mellifera), but studies have shown that large densities not only impact negatively on pollination services but affect pollinator communities as a whole. Here we study plant flower visitation by potential pollinators in a remnant patch, invaded by exotic plants, adjacent to a macadamia orchard in a heavily transformed, commercial agricultural landscape. The impact of IAPs on flower visitor community composition (abundance and species richness) was assessed using two field methods of observation methods (camera trap and visual observation). Relative to visual observation, camera traps recorded smaller species and those that tend to avoid humans, while rarer species were more prevalent in visual observation. Therefore, camera traps observed more species at a sampling point, but less species overall. Observational methods are explained by the largest amounts of conditional variation. IAPs and native plants were visited by a larger and diverse set of flower visitors than macadamia although macadamia flower densities were twice as high and covered a much larger extent. IAPs were more generalist in the flower visitors they attracted. Native plants were more specialized in the flower visitors they attract with GLMM suggesting although not significantly were associated with more species richness. These plants were also associated with overall visitation of species. More visitation of Apis mellifera were on IAP’s and native plants which contrast with macadamia with less than 10%. However, this small amount account for 65% of all macadamia flower visitations, the remainder was largely (33%) made up by Eristalis tenax. Dominant flower visitors seemed to avoid A. mellifera by partitioning their activity in time or iii specializing on certain plant species. The importance of IAP’s in providing forage to A. mellifera before macadamia flowering periods are noted. However, this probably has negatively impacted on other potential native pollinators of macadamias (e.g. Eristalis tenax). The removal of IAPs around mass flowering native plants such as Gymnanthemum myrianthum, should support and facilitate the second most common flower visitor of macadamia, E. tenax and flower visitors in general.Item Open Access Ecology and management of bat communities to increase pest control in macadamia orchards, Limpopo , South Africa(2019-05-18) Weier, Sina Monika; Taylor, Peter J.; Tscharntke, Teja; Grass, IngoAn ever growing human population and accelerating land use change is associated with the loss of species and their ecosystem services. Agricultural intensification has led to a worldwide threat of extinction to about one quarter of all bat species, despite the valuable ecosystem service of pest control provided by bats. The decline in bat populations is mainly attributed to the loss or fragmentation of habitats, roost sites and feeding opportunities related to agricultural intensification and land use change. Therefore, proactive management of bat communities in agricultural landscapes is essential. South Africa is the world’s largest producer of macadamias and the industry continues to grow. This study gains insight into the habitat use and foraging behaviour of insectivorous bat species on a temporal and spatial scale, in and around macadamia orchards in order to advise management strategies on how to increase bat activity and, possibly, pest control. It also focuses on the preferences of artificial roost sites used by insectivorous bats in macadamia orchards. The diet of insectivorous bat species is especially difficult to study and the least invasive tool to gain information is the study of bat faecal pellets. In order to provide evidence for the consumption of pest insect species by bats and thus incentive to farmers for a more integrated pest management approach (IPM), this study explored molecular approach to insectivorous bat diet analyses using fragment analysis of bat faecal pellets with fluorescent-labelled species-specific primers (designed for the CO I gene). This study was conducted in the subtropical fruit growing area of Levubu, Limpopo province, South Africa between the towns Thohoyandou (22°59'03.7 S, 30°27'12.8 E) and Makhado/Louis Trichardt (23°03'03.6 S, 29°55'12.7 E). Levubu also accounts for the second highest production of macadamia in South Africa. An introduction to the order Chiroptera and into the relevance of insectivorous bat species to agriculture as well as the importance of a more integrated pest management approach (IPM) focusing on bats is provided in Chapter One. Bats were acoustically monitored and light traps were used to catch arthropods during one annual cycle. I sampled five macadamia orchards once a month from September 2015 to August 2016 and used GIS and R to analyse both the general bat activity and foraging bat activity of the two main foraging guilds (open-air/clutter edge guild) in different land use types as well as total bat activity with respect to arthropod abundances. As reported in Chapter Two, results show that the overall clutter edge guild activity (number of passes) decreased with macadamia and orchard (all other fruit) cover in the macadamia high season (December to end of May) and increased with bush cover and distance to settlements (potential roosts) in the macadamia low season (June to end of November). Open-air guild activity increased with fallow cover (uncultivated grassland with scattered trees and shrubs) in the high season. Foraging activity (feeding buzzes) of the clutter edge guild increased with bush cover over the whole year. Total activity (both guilds) increased with abundance of true bugs (Hemiptera), including the main macadamia pests, and bush cover. Macadamia cover has a negative effect on the activity of the clutter edge guild in the high season, with low activity in the orchard center (high cover), and activity increasing in a linear way with decreasing orchard cover at the orchard edge (low cover). These results suggest that the clutter edge guild prefers foraging close to the edges of the orchards rather than in the center, while the open-air guild prefers semi-natural habitats (fallow). When numbers of pest arthropods drop in the macadamia orchards, the natural land use type, bush, becomes a more important foraging habitat and thereby increased the activity of the clutter edge guild. From June 2016 to July 2017, I scanned 31 bat houses, mounted on poles on six macadamia orchards, for bats or any other occupants such as wasps, birds and bees. Twenty-one multichambered bat houses of three slightly different chamber designs were erected on poles, in sets of three. Additionally, five bat houses of the type ‘Rocket box’, four bat houses in sets of two (black and white) and one colony bat house were erected. Bats were counted and visually identified to family or species level. From December 2016 to end of March 2017, three IButtons were installed to record temperature variation between one set of three bat houses. As reported in Chapter Three, results show that the central bat house in the set of three and the black bat house in the set of two had a significantly positive effect on bat house occupancy. There was a significant difference in the mean temperature between the houses in the set of three, with a significant difference in temperature of 0.46°C between the central and the first bat house. The three bat houses erected in sets varied slightly in their chamber design, with the central bathouse having the most chambers (six), while the bat houses to either side had less chambers (four), set at an angle or straight. This and the insulation to either side by the other bat houses is assumingly what caused the central bat house to be on average warmer. The Yellow-bellied house bat (Scotophilus dinganii) was by far the most recorded and the only species observed to co-habitat a bat house with another animal species, in particular honeybees. The study might confirm assumptions in that the microclimate of bat houses, respectively their insulation, sun exposure and color appear to be important factors influencing bat house occupancy. The two preferred bat houses in our study were the black, in the set of black and white, as well as the central, and on average warmest bat house, in the set of three. I collected bat faecal pellets with two different methods between July 2015 and April 2017 to determine the prevalence of pest insects in faecal pellets. Eighteen of the bat houses (in sets of three) on three different farms and two Egyptian slit-faced bat (Nycteris thebaica) roosts were fitted with trays in order to collect pellets from those occupied by bats. I noted occupancy of bat houses to species or family level to keep disturbance minimal. Additionally, I collected pellets from individuals captured by means of mist nets and harp traps. Four of the main pest-insects; the two-spotted stinkbug (Pentatomidae: Bathycoelia distincta), the green vegetable bug (Pentatomidae: Nezara viridula), the macadamia nut borer (Tortricidae: Thaumatotibia batrachopa) and the litchi moth (Tortricidae: Cryptophlebia peltastica), were collected from pheromone traps or after scouting for primer development and optimisation. After extracting DNA from the bat faecal samples the target regions were amplified in a multiplex PCR and fluorescently labelled PCR amplicons were analysed and interpreted. In order to verify multiplex analyses results, all samples were amplified with all four sets of primers in plates and those that produced amplicons were purified and sequenced. As reported in Chapter Four, results show that fragment analyses yielded a total of 63 out of 103 samples tested positive for pest insect species (61%) with a total of 92 positive fragments. Primer specificity could be confirmed to 100% for the sequences obtained for Bathycoelia distincta (26/26) and Nezara viridula (12/12) primers but not for all sequences obtained fot Cryptophlebia peltastica (18/30) and Thaumatotibia batrachopa (1/14) primers. One sample showed no positive fragments but contained a positive sequence for N. viridula. Three samples tested positive for one pest-species fragment but contained a positive sequence for a second pest-species (B. distincta, T. batrachopa and C. peltastica). Adding four positive fragments and one additional positive sequence to the data. This means that sequences of pest insect species were obtained from 54 out of the 103 samples (55.6%) with a total of 73 pest insect sequences. For the high season (December to end of May) a total of 37 positive fragments for the four pest insect species and 24 negative samples were yielded and for the a low season (June to end of November) a total of 36 positive fragments and 15 negative samples. Looking at the pest consumption of the different bat species or families, our results show that all of them foraged on pest insect species. Whereas, all species and families except Myotis bocagii and Rhinolophus simulator (for which N<2) foraged on both the Lepidopteran and Hemipteran pest species. Therefore, all families of bats of which faecal pellets were analysed for this study (Molossidae, Nycteridae, Rhinolophidae and Vespertilionidae) foraged on one or more of the four pest insect species. In summary, Chapter Five concludes that natural and semi-natural vegetation promote bat activity in macadamia orchards, and potentially bats' provision of the ecosystem service of pest control. In times of accelerating land use change, remnants of natural vegetation are important refuges and need to be maintained or restored to conserve bat species and promote their ecosystem services. The study also shows that bat activity might be improved by adding roosting opportunities to orchards. Warm and well-insulated bat houses mounted freestanding on poles and in sets appeared to work best in northern South Africa. Further research on co-habitation of bat houses and displacement behaviour as well as the potential importance of altitude and distance to water is needed. All of the species or families of bats from which faecal pellets were collected have been confirmed to forage on at least one of the four pest insects and the bat species have shown to be much more generalist and presumably opportunistic feeders than previously assumed. Thus, this study provides incentive and advice to farmers for a more integrated pest management approach (IPM).Item Embargo Ecology and phenology of Melia Azedarach Linn.on and off the Riverine Areas(2024-09-06) Masia, Khathutshelo Victor; Ligavha-Mbelengwa, M. H.; Mokganya, M. G.Noteworthy, Melia azedarach Linn. is an indispensable tree species that is utilised in various forms. It can be used in craft industries as a substitute for teak wood when the supply is reduced. Simultaneously, its leaves, roots, bark, and flowers are used as medicines and natural pesticides. Melia azedarach Linn. is traditionally used as medicine to treat astringents and furthermore can be used against intestinal worms, skin diseases, stomachaches, uterine illnesses, and as a diuretic and febrifuge. In addition, it has been reported to possess anticancer, antimalarial, analgesic, and anti-inflammatory, antifungal, antibacterial and antioxidant activities. This tree can adapt to different environmental conditions so that it can grow well in extensive areas. Melia azedarach Linn. is a plant that grows both on and off the riparian zones. Communities in South Africa see less value attached to it to the extent that in many places where these trees are found growing, the majority are cut for no good reason. Sometimes, the plant species is cut for the construction of fences, kraals, or firewood. The main reason for this practice is that much is not known about the plant; it could be found de-vegetated anytime. The study was conducted at Ha-Tshikonelo, Thulamela Local Municipality, Limpopo Province, South Africa. Plant phenology and distribution have gained increased interest because climatic change is sensitive to phenological traits and their consequences for ecosystem function. It is made possible to gather information on spatial and ecological scales because of new technologies innovative technologies. Temperature, photoperiod, and winter chilling are examples of plant phenology drivers, and competition is included. A smartphone ( Huawei Nova Y60) camera was used to take pictures of phenological changes when visiting the on and off riparian zones from August 2019 to December 2021. The research aimed to determine the different phenophases and distribution patterns of Melia azedarach in riparian zones. The Nearest-neighbour method of sampling individuals within a population of plants was used for data collection. The collected data was then analysed using Analysis of Variance (ANOVA). It was found that Melia azedarach Linn. is regularly distributed for both on and off-riparian areas. Phenophase occurring off riparian zones was found to be occurring earlier than in riparian zones. It was found that Melia azedarach Linn. is surviving and flourishing in both off and on the riparian zones. On riparian zone individuals were growing bigger than those found off the riparian zones because of the abundant supply of resources such as water and nutrients.Item Open Access Ecosystem services and disservices of ants in subsistence farming (Limpopo Province) : an experimental approach in mango orchards.(2017-08-18) Maphote, Vongani Terrence; Foord, S. H.; Tscharntke, T.; Grass, I.; Lauer, F.; 632.796096825See the attached abstract belowItem Open Access The edge effects of mango farming on flower visitor insect communities and epigeal ant species in Northern-Eastern South Africa(2015-09-15) Simba, Lavhelani Dembe; Foord, S. H; Seymour, C. LItem Embargo Effects of anthropogenic factors on the population structure of Pterocarpus angolensis DC in a communal area of Khalavha Village in Vhembe Biosphere(2024-09-06) Ndou, Tshihumbudzo; Tshisikhawe, M. P.; Mashile, S. P.Pterocarpus angolensis DC. is an indigenous species of value across Africa. The species have been identified as having a high utilization rate for different purposes. The purpose of the study was to analyze the population structure of P. angolensis, a species in high demand. Ethnobotanical information was collected with an aid of a questionnaire from fifty-three informants. The informants identified two plant parts preferred by the community. The only preferred parts are stem (67%) and bark (33%). The study identified a lack of indigenous knowledge of the species amongst the youth. Some of the uses reported on P. angolensis were firewood (n=33), medicine (n=43), craftwork (n=35), protection (n=16), and timber (n=4). The transect sampling technique was used to document ecological data on the species to analyze its population structure. Fifty-three transects of 100m x 10m were constructed within the population. Ecological parameters recorded included stem diameter, height, and crown health status. Basal stem diameter data recorded on P. angolensis sampling were grouped into seven size classes and displayed an inverse J-shaped curve when analysed. The study showed that the population had more individuals (n=60) within the seedlings size class (0-5cm) when compared to the bigger size classes (20.1-25cm, 25.1-30cm, and >30.1cm). The majority (37%) of P. angolensis individuals had light crown damage which depicts on average an aspect of healthy crowns. Only 1% of sampled individuals had dead crowns. Monitoring of the P. angolensis population will assist in making sure that it stays healthy and viable.Item Open Access The effects of debarking and seasonal variations on physical structure; phenolic content and biological activities of Sclerocarya Birrea in the Nylsvley Nature Reserve(2016-05) Nndwammbi, Matodzi; Ligavha-Mbelengwa, M. H.; Ramaite, IDISee the attached abstract belowItem Open Access The effects of experimental drought, grazing, and seasonality on ant and spider diversity in an arid region of South Africa(2020-04) Ratshibvumo, Tshikambu; Foord, S. H.; Munyai, T. C.Coupled with irreversible shifts, climate-driven disturbance of ecosystems will probably be the largest impact of climate change on humans. With higher rainfall variability and more intense events, separated by extended dry periods, semi-arid rangelands will be severely altered. Adding to these climatic events, livestock grazing is one of the most common land use practices globally, which will increase as human populations grow. The magnitude of these synergies between drought and grazing could also vary with season. Our understanding of faunal response to the interaction of both drought and grazing is limited. This study investigated the response of ants and spiders, two dominant components of epigeal invertebrate assemblages, to a long-term drought and grazing experiment. The experiment consisted of four 40 x 40 m blocks, each with nine 10 x 10 m plots. Drought was simulated using rainout shelters, whilst grazing was manipulated by excluding livestock from the plots using ~ 1 m high fence around the plots. Ants and spiders were collected seasonally in a blocked and two-way crossed experiment using a total of 96 pitfall traps. Both ant and spider size were assessed using community weighted mean. Grazing treatment had the bigger impact on ants than drought, as they got smaller, functionally less diverse and less active with grazing. The interaction between grazing and drought encouraged the increase in activity of large ants. There was an interesting interaction between grazing and drought, plots with grazing had smaller ants than plots without grazing, but only in plots for which there had been drought. This could be attributed to antlion abundance and how they interact with grazing on the specific plots. Assemblage level analysis confirmed the importance of size in structuring these communities, with larger species of ants associated with open and dry habitats. In contrast, spiders were more responsive to drought than grazing treatments. The spider response to the treatments was in conjunction with seasonality, with spider richness decreasing with cold, dry season (winter) and hot, dry season (spring) respectively. Spiders also became less active during the dry seasons. Interestingly, smaller spider species were more active during cold, dry season, and larger species were more active during the hot, dry season where there is no grazing. At assembly level, grazing and no drought interaction encouraged mobile species that were more of active hunters, as open habitats are ideal hunting ground. Our findings clearly suggest that both long-term drought and grazing have an impact on ants and spiders. How these taxa respond to long-term effects on drought and livestock grazing in semi-arid rangelands in the face of climate change is likely to shed light also on how other invertebrates are likely to be affected, and what it could mean for the ecosystem as whole. Further studying is needed to uncover other underlying changes, how that affects and shapes the semi-arid rangeland ecosystems in the long-term.