Mopane Research Articles

Local extirpation of woody species in Colophospermum mopane woodland under chronic utilisation by elephants

AbstractThe hypothesis that certain woody species may be prone to local extirpation under chronic elephant utilisation was examined for Colophospermum mopane open woodland, for an area within the foraging range of elephants from permanent water. Elephant density increased from nearly absent in the 1970s to >3 elephants km−2, with 0.62 adult bulls km−2, by 2022. Study components of vegetation impact included a long‐term elephant exclosure, a fence‐line contrast with an adjacent communal area, comparison with an adjacent wildlife reserve carrying a fifth of the elephant density and the use of historical studies of the vegetation. A history of elephant utilisation resulted in woodland becoming hedged through pollarding of tree stems by elephants. Impacted woodland was characterised by a slightly lower tree density, reduced average height of trees, altered shrub composition and lower species richness. The dominant C. mopane and sub‐dominant species had persisted. However, about 14 species were potentially trending towards local extirpation on account of very high levels of adult mortality, but had persisted because of a low level of seedling recruitment. Fleshy fruits were a shared attribute among most extirpation‐trending species, which, together with a reduction in woody species richness that affects browsers, has ramifications for trophic flows.

Impacts of Wildlife Artificial Water Provisioning in an African Savannah Ecosystem: A Spatiotemporal Analysis

The use of artificial water points for wildlife in African savannah ecosystems has been widely criticised for affecting the distribution of wildlife and initiating changes in the heterogeneity of natural landscapes. We examined the spatiotemporal variations in the landscape before and after the installation of an artificial water point by integrating the analysis of vegetation and soil spectral response patterns with a supervised learning random forest model between 2002 and 2022 in Chobe Enclave, Northern Botswana. Our results revealed that the study area is characterised by animal species such as Equus quagga, Aepyceros melampus, and Loxodonta africana. The findings also showed that the main vegetation species in the study area landscape include Combretum elaeagnoides, Vachellia luederitzii, and Combretum hereroense. The artificial water point induced disturbances on a drought-vulnerable landscape which affected vegetation heterogeneity by degrading the historically dominant vegetation cover types such as Colophospermum mopane, Dichrostachys cinerea, and Cynodon dactylon. The immediate years following the artificial water point installation demonstrated the highest spectral response patterns by vegetation and soil features attributed to intense landscape disturbances due to abrupt high-density aggregation of wildlife around the water point. Landscapes were strongly homogenised in later years (2022), as shown by overly overlapping spectral patterns owing to an increase in dead plant-based material and senescent foliage due to vegetation toppling and trampling. The landscape disturbances disproportionately affected mopane-dominated woodlands compared to other vegetation species as indicated by statistically significant land cover change obtained from a random forest classification. The woodlands declined significantly (p < 0.05) within 0–0.5 km, 0.5–1 km, 1–5 km, and 5–10 km distances after the installation of the water point. The results of this study indicate that continuous nonstrategic and uninformed use of artificial water points for wildlife will trigger ecological alterations in savannah ecosystems.

Repeated clearing as a mechanism for savanna recovery following bush encroachment

Abstract Many savannas are experiencing increased cover of trees and shrubs, resulting in reduced herbaceous productivity, shifts in savanna functional structure and potential reductions in ecotourism. Clearing woody plants has been suggested as an effective management strategy to mitigate these effects and restore these systems to an open state with higher rates of grass production and herbivory. This study investigated the effectiveness of repeated shrub clearing as a tool to mitigate bush encroachment in a semi‐arid savanna in southern Africa. We present data from a 7‐year experiment in the Mthimkhulu Game Reserve bordering Kruger National Park, South Africa. Colophospermum mopane stems and resprouting shoots were basally cut 2–3 times per year (2015–2022) in three pairs of treatment and control plots of 60 × 60 m. We monitored changes in soil moisture, grass biomass and herbivore activity via dung counts. We assessed C. mopane physiological responses to repeated cutting using non‐structural carbohydrates and stable water isotopes to infer changes to energy storage and functional rooting depth, respectively. The cleared treatment had higher soil moisture and grass biomass than the control treatment. Dung counts showed impala and buffalo visited the cleared treatment more frequently than the control treatment. Repeated cutting had limited effects on C. mopane survival in the first 2–3 years after initial clearing, but 80% of individuals were dead after 7 years. Repeatedly cut C. mopane had lower belowground starch concentrations and used water from shallower soil depths than C. mopane in control plots. Synthesis and applications. Repeated cutting increased soil moisture availability and grass biomass, and attracted charismatic grazing herbivores. While more costly than once‐off clearing methods, this practice created more employment opportunities for a neighbouring rural community. Transforming portions of the ecosystem to a grass‐dominated state may increase ecotourism potential through improved game viewing in open systems.

Host tree-based scenario modelling for predicting a key edible insect, mopane worm Gonimbrasia belina (Westwood, 1894) distribution in Southern Africa

Abstract Gonimbrasia belina, known as the mopane worm, is a large edible caterpillar in tropical and subtropical regions. However, little is known about the bioecology of this species as influenced by its host trees. This study evaluated the importance of different potential host trees in understanding mopane worms’ behaviour and spatial distribution. To assess their relative importance, the study compared models incorporating various mopane worm host trees and predictor variables. Using the species distribution modelling (SDM) package in R, an ensemble of random forest (RF), support vector machine (SVM), and boosted regression tree (BRT) algorithms were used to assess the spatial extent of mopane worm distribution in Southern Africa. Four host tree-based scenarios were developed to assess their contribution to the relative distribution of the mopane worm i.e. (1) by excluding all the potential host trees as explanatory variables and considering only the environmental variables, (2) focusing on the primary host tree, Colophospermum mopane as an explanatory variable together with the other environmental variables, (3) incorporating all the host trees, including C. mopane and (4) examining all other host trees excluding C. mopane. Results demonstrated that incorporating all host trees enhanced the models’ predictive abilities (mean AUC = 0.87) underscoring the significant impact of the alternative host trees on the mopane worm distribution patterns beyond just the C. mopane. This study highlights the significance of host trees in predicting the behaviour and distribution of mopane worm populations, providing valuable insights and decision-making for mopane worm use as an alternative protein source, conservation efforts, and land management practices.

Emergent trees in Colophospermum mopane woodland: influence of elephant density on persistence versus attrition.

Colophospermum mopane (mopane) forms mono-dominant woodlands covering extensive areas of southern Africa. Mopane provides a staple foodstuff for elephants, who hedge woodland by reducing trees to small trees or shrubs, leaving emergent trees which are too large to be pollarded. Emergent trees are important for supporting faunal biodiversity, but they can be killed by ringbarking. This study first examined the influence of elephant density on woodland transformation and the height distribution of canopy volume, and, second, whether canopy volume is maintained, and tall emergent trees too large to be broken can persist, under chronic elephant utilisation. Three regimes of 0.23, 0.59 and 2.75 elephants km-2 differed in vegetation structure and the height structure of trees. Areas under the highest elephant density supported the lowest total canopy volume owing to less canopy for plants >3 m in height, shorter trees, loss of most trees 6-10 m in height, but trees >10 m in height (>45 cm stem diameter) persisted. Under eight years of chronic utilisation by elephants, transformed mopane woodland maintained its plant density and canopy volume. Plant density was greatest for the 0-1 m height class, whereas the 3.1-6 m height class provided the bulk of canopy volume, and the 1.1-3 m height layer contained the most canopy volume. Emergent trees (>10 m in height) suffered a loss of 1.4% per annum as a result of debarking. Canopy dieback of emergent trees increased conspicuously when more than 50% of a stem was debarked, and such trees could be toppled by windthrow before being ringbarked. Thus relict emergent trees will slowly be eliminated but will not be replaced whilst smaller trees are being maintained in a pollarded state. Woodland transformation has not markedly reduced canopy volume available to elephants, but the slow attrition of emergent trees may affect supported biota, especially cavity-dependent vertebrate species, making use of these trees.

Hungry herbivores and thirsty plants: Browsing wildlife shape savanna tree transpiration independently of water use strategies

Abstract Plant transpiration is a key component of the hydrological cycle that moves water from the soil through plants to the atmosphere and is largely determined by environmental conditions. The challenges of highly variable climatic conditions and water scarcity in the semi‐arid savannas of southern Africa drive trees to exhibit different water use strategies. An additional challenge for savanna trees arises from the browsing of large mammals, and its potential impact on transpiration has largely been overlooked. To assess water use strategies and the impact of browsing on transpiration in three common savanna woody species (Colophospermum mopane, Catophractes alexandri, Senegalia mellifera), we conducted an extensive field experiment in a wildlife reserve in Namibia. We established a browsing gradient ranging from 0% to 100% leaf removal to disentangle complex relationships, and we measured sap flow representing whole‐tree transpiration, stomatal conductance as a proxy for leaf level transpiration, and environmental factors including soil moisture, solar radiation, air temperature and air humidity. We discovered a unimodal relationship between browsing intensity and sap flow, consistent across all species, and peaking at low to moderate browsing levels equivalent to approximately 30% leaf removal. This universal pattern is remarkable since we found water use strategies to differ among species: Colophospermum mopane and C. alexandri exhibit a water‐saving behaviour to reduce water loss under unfavourable conditions while S. mellifera demonstrates water‐spending characteristics. The deviation from a negative linear effect of browsing does not meet the functional expectation when browsing is translated into a simple leaf area reduction. Instead, it can be attributed to stomatal adjustments that partially compensate for transpiratory surface loss. We propose that this conceptual mechanism can be generalised to other woody species and various ecosystems. In addition, common transpiration models relying solely on leaf area indices and abiotic factors can be improved by including a non‐linear relationship to reproduce the effect of browsing accurately. Our findings highlight the role of herbivores in shaping the connection between the Earth's spheres and improve our understanding of ecohydrological and vegetation dynamics in Southern African savannas. Read the free Plain Language Summary for this article on the Journal blog.

Are Mopani Worms a Mechanism for Mopane Tree (Colophospermum mopane) Conservation? An Evaluation of the Villages Around Giyani, Limpopo Province, South Africa

Background and Background Aims Colophospermum mopane provides many benefits including mopani worms, firewood, timber for construction, and medicine. Despite C. mopane playing a significant role in the lives and livelihoods of communities within their range, they are destroyed because of unsustainable harvesting practices coupled with lack of management practices. Assessment of people’s attitudes has become significant in studies dealing with the conservation of biodiversity. This study aims to assess the attitudes of local communities in and surrounding Giyani in Limpopo Province in South Africa towards the mopane tree and to determine if their attitudes relate to obedience to traditional rules and regulations. Methods Interview-administered questionnaires were used to systematically select 161 households in Muyexe village and 82 households in Nsavulani village. The questionnaire evaluated the biographical data of respondents, knowledge of mopane woodlands, importance of mopane trees and mopani worms, and their attitudes towards mopane tree conservation. Results The overwhelming majority of respondents in both villages had positive attitudes towards mopane trees for ethical reasons. Respondents were also positive that mopane trees should be protected for future generations. The positive attitude of most respondents relates to obedience to rules and regulations that do not allow cutting of wet C. mopane. Respondents only cut dead or dry mopane woodlands for fuelwood. Cutting or harvesting was done on a subsistence and sustainable basis. Conclusion The communities have shown that they are guardians of C. mopane. The study concluded that mopani worms serve a mechanism for C. mopane conservation in Muyexe and Nsavulani villages in South Africa. Implications for conservation The positive attitudes of local communities, and obedience to the customary rules and regulations is a positive sign not only for ethical reasons, but also for long-term mopane woodlands conservation. This approach encourages the long sustainability of mopane woodlands in the study area.

Spatio-temporal usage of water sources by Black-cheeked Lovebirds Agapornis nigrigenis: implications for conservation planning

Summary The Black-cheeked Lovebird Agapornis nigrigenis has a highly restricted range in dry south-western Zambia, where its distribution is clumped and localised in association with mopane Colophospermum mopane woodland and permanent water pools. Fieldwork and monitoring over 30 months between December 2018 and October 2021 established that the lovebirds’ usage of pools for drinking was higher towards the centre of the bird’s distribution and influenced by the pools’ proximity to mopane woodlands, surrounding tree cover, and level of human activity. Of the four pool types available for use by lovebirds (i.e. mopane, grassland, river, and artificial), mopane and grassland pools were disproportionally susceptible to drying out in the dry season, hence showed greater variation in numbers of visiting birds compared with the other two types. Lovebirds showed a preference for pools with a perimeter of <50 m and tended to avoid those with a perimeter >100 m, consistent with a positive association between pool size and human activity. Convergence between humans and lovebirds in dependence on water resources and mopane woodland points to the need to find ways to overcome potential conflicts. Such ways include creating small, shallow-sided, undisturbed pools in or near mopane woodland, extending water retention in existing mopane pools, and enhancing the capacity of artificial pools to meet the needs of the lovebirds.

Allometric relationships between sapwood area and shrub dimensions for six common Southern African savanna bush encroacher species: Universal or species‐specific?

AbstractSouthern African savanna rangelands are facing a widespread degradation pattern called bush encroachment. This is associated with implications for various aspects of the water cycle and in particular canopy transpiration. At the individual‐tree scale, it is estimated by scaling sap‐flux density by sapwood area. However, the direct measurement of sapwood area is impracticable at landscape scale and general allometric equations of the West‐Brown‐Enquist (WBE) model relating sapwood area to primary size measures seem to fail for some species and climates. Therefore, we conducted intensive field measurements to establish species‐specific allometric relationships between sapwood area and sizes (stem diameter, crown area) in six dominant shrub species involved in bush encroachment in Namibia (Colophospermum mopane, Senegalia mellifera, Vachellia reficiens, Dichrostachys cinerea, Vachellia nebrownii, Catophractes alexandri). We found strong allometric relationships between sapwood area and stem diameter as well as between sapwood area and crown area for all six species. These relations are largely in line with the WBE theory but still provide estimates that are more accurate. Only in D. cinerea, the sapwood area was significantly smaller than predicted by the WBE theory, which might be caused by a larger need for stabilizing heartwood. Our results are useful to estimate water loss via transpiration at a large scale using remote sensing techniques and can promote our understanding of the ecohydrological conditions that drive species‐specific bush encroachment in savannas. This is particularly important in the light of climate change, which is considered to have major implications on ecohydrological processes in savannas.

An outbreak of Gynanisa maja (Lepidoptera: Saturniidae) larvae in the south-eastern lowveld of Zimbabwe.

The larvae of speckled emperor moths (Gynanisa maja) are important plant defoliators in savanna ecosystems of southern Africa and a valuable food resource for indigenous communities. Population explosions of G. maja larvae can negatively impact an area's primary productivity thereby altering herbivory patterns and associated ecosystem processes. Harvests of the larvae enhance socio-economic livelihoods of local people by providing a source of protein and improving household incomes. We report on a population outbreak of G. maja larvae that occurred in south-eastern Zimbabwe between December 2022 and January 2023 and discuss the ecological and social significance of the event. A total biomass weight of 5811 tons of G. maja larvae was estimated over the area of the outbreak and extensive defoliation was recorded in Colophospermum mopane trees. We could not associate the outbreak with any obvious environmental conditions and speculate that it may have been caused by subtle triggers that are not easily identified.

Mopane (Colophospermum mopane): A potential winner under climate change in southern Africa

AbstractDistribution and abundance under climate change of particularly non‐timber forest product tree species is vital since they sustain many livelihoods, especially in rural sub‐Saharan Africa. The aim of the study was to determine the current and future natural range of mopane (Colophospermum mopane (J. Kirk ex Benth.) J. Léonard, Fabaceae), a dominant tree species in mopane woodlands of southern Africa. An ensemble model was built in ‘biomod2’ from eight algorithms and used to estimate the current and future distribution. Seven bioclimatic variables and 269 occurrence records were used to calibrate individual models that were later combined into an ensemble model. The ensemble model was projected to two time periods, 2041–2060 and 2081–2100, under two shared socio‐economic pathways (SSPs), SSP2‐4.5 and SSP5‐8.5, and three general circulation models (GCMs). The ensemble model showed high performance (KAPPA = 0.770, ROC = 0.961, TSS = 0.792, ACCURACY = 0.900). A map of the current distribution shows occurrence predominantly in low‐lying areas, including the Zambezi, Save and Limpopo valleys, Okavango and Cuvelai basins, and in southern and central Mozambique. Projection maps show expansion under all SSPs, GCMs and time periods. Averaged across GCMs in 2041–2060, the range expanded by 22.37% under SSP2‐4.5, and by 19.94% under SSP5‐8.5. In 2081–2100, the range expanded by 20.43% under SSP2‐4.5, and by 27.62% under SSP5‐8.5. Notably, the range expansion was highest under SSP5‐8.5, an SSP that envisages unmitigated greenhouse gas release and the largest mean global temperature increase. It is highly likely that mopane is not directly threatened by climate change. Indirect climate change threats, however, remain uncertain.

Prevalence, molecular and phenotypic profiles of arboreal associated Cryptococcus neoformans in Botswana

Mopane tree (Colophospermum mopane) is one of the main ecological niches of Cryptococcus neoformans, an opportunistic fungal pathogen that causes cryptococcosis primarily on immunocompromised hosts after inhalation of basidiospores from the environment. Hence, we investigated the prevalence, and phenotypically (antifungal resistance and biofilm formation capacity) and genotypically (mating type and genetic structure) characterized C. neoformans isolated from C. mopane, Acacia tortilis, Adansonia digitata and Ziziphus mucronata in Botswana. We report 7.1% and 2.9% prevalence of C. neoformans in C. mopane and other trees, respectively. All tested C. neoformans isolates were determined to be non-WT to fluconazole. Most isolates (65%) of C. neoformans isolates were biofilm producers. Mating type determination revealed a higher proportion of the globally rare MATa allele (53%) and a single MATα/MATa hybrid. The observed genotypeswere VNI (71%), VNB (23%) and VNB/VNB hybrids (6%). Native trees other than C. mopane are alternative ecological niches of antifungal resistant C. neoformans, and this represents a serious public health concern,and this represents a serious public health concern, especially for high-risk populations. Prevalence of C. neoformans on native trees and the observed emergence of hybrids (evidence of sexual recombination) highlight the need for increased surveillance and risk assessment within a One Health paradigm.

Role of Indigenous and local knowledge in seasonal forecasts and climate adaptation: A case study of smallholder farmers in Chiredzi, Zimbabwe

Accessible, reliable and diverse sources of climate information are needed to inform climate change adaptation at all levels of society, particularly for vulnerable sectors such as smallholder farming. Globally, many smallholder farmers use Indigenous knowledge (IK) and local knowledge (LK) to forecast weather and climate; however, less is known about how the use of these forecasts connects to decisions and actions for reducing climate risks. We examined the role of IK and LK in seasonal forecasting and the broader climate adaptation decision-making of smallholder farmers in Chiredzi, Zimbabwe. The data were collected from a sample of 100 smallholder farmers. Seventy-three of the 100 interviewed farmers used IK and LK weather and climate forecasts, and 32% relied solely on IK and LK forecasts for climate adaptation decision-making. Observations of cuckoo birds, leaf-sprouting of Mopane trees, high summer temperatures, and Nimbus clouds are the main indicators used for IK and LK forecasts. The use of IK and LK climate forecasts was significantly positively associated with increasing farmer age and farmland size. Farmers using IK and LK forecasts implemented, on average, triple the number of adaptation measures compared with farmers not using IK and LK. These findings demonstrate the widespread reliance of farmers on IK and LK for seasonal forecasts, and the strong positive link between the use of IK and LK and the implementation of climate adaptation actions. This positive association between IK and LK usage and the implementation of adaptation actions may be widespread in smallholder farming communities throughout Africa and globally. Recognition and inclusion of IK and LK in climate services is important to ensure their continued potential for enhancing climate change adaptation.

Socio-Economic Benefits of Colophospermum mopane in a Changing Climate in Northern Namibia

Millions of local communities in southern Africa depend on forest ecosystems and the goods and services they provide for their livelihoods. This paper aims to assess the socio-economic benefits of forest goods and services in a changing climate by focusing on the forest products of Colophospermum mopane (C. mopane) in the Kunene and Omusati regions in northern Namibia. We used C. mopane product data from 2011 to 2021. Our analyses showed that local communities harvested five main products from C. mopane, namely firewood, poles, droppers, rafters, and roots. Firewood and poles were the primary C. mopane products harvested by local communities, mainly for subsistence use. Our results suggest that C. mopane potentially continues to the provision of goods and services for the livelihood of local communities, despite the changing climate in northern Namibia. We propose future studies in predictive analysis focus on extreme weather events, such as forest fires, droughts, floods, and other climate-related hazards that affect goods and services provided by forest ecosystems in the northern regions and the entire country.

Impact of artisanal gold mining on woody vegetation in Chewore South Safari Area, northern Zimbabwe

The study assessed the impact of artisanal gold mining on the composition and structure of woody vegetation in Chewore South Safari Area (CSSA), northern Zimbabwe. The study area was stratified into two strata, namely, the mined area and the unmined area. Using random computer-generated points, 20 plots were sampled in the mined area and 20 plots were sampled in the unmined area. Each plot size measured 20 m × 30 m and the following were measured or recorded: the status of trees, tree species, species occurrences, stem circumference and tree height. Data were collected between January and February 2018. No significance differences (P > 0.05) were recorded in woody tree species diversity and tree height between the mined and unmined areas. In contrast, woody tree density (P = 0.049), basal area (P = 0.050), the occurrences of dead trees (P = 0.011) and damaged woody trees (P = 0.002) were significantly different between the mined and unmined areas. The TWINSPAN analysis divided the woody vegetation of CSSA into two groups of woody tree species assemblages, namely Colophospermum - Combretum closed woodlands on the unmined area and Colophospermum mopane - Brachystegia open woodlands on the unmined area. The study highlights that artisanal gold mining in CSSA contributes to damage and mortality of woody trees and will likely cause long term environmental disturbances and related consequences. The study recommends the need of appropriate authorities to work towards enhancing environmental awareness and enforcing policies and laws to prohibit mining in protected areas.

The Effect of Woody Encroachment on Evapotranspiration in a Semi-Arid Savanna

Over the past century, increases in indigenous woody plant species, also known as woody encroachment (WE), has occurred in grasslands and savannas across the globe. While the impact on grassland and savanna composition and productivity has been well studied, little is known of the impacts on the hydrological cycle. WE may increase evapotranspiration (ET) losses, leading to reduced infiltration and ultimately reduced freshwater availability, which is of particular concern in arid and semi-arid areas. The aim of this study was to determine the effect of Colophospermum mopane (mopane) encroachment on ET in a semi-arid savanna located in South Africa. Mopane is widely distributed across southern Africa, and is one of the main encroaching species of the region. Following an assessment of the validity of two surface renewal approaches, SR1 and SRDT, against short eddy covariance campaigns for sensible heat flux estimation, the SR1 approach was used to estimate ET at an experimental woody plant clearing trial from November 2019 to July 2022. For the two drier years of the study, the removal of mopane trees had little effect on ET. However, for the wettest year of the study, the removal of mopane trees decreased ET by 12%, supporting the hypothesis that the conversion from grass dominance to woody dominance can increase ET. Annual ET exceeded annual rainfall in all 3 years, indicating that the vegetation supplements its water use with soil water that has accumulated during previous wet seasons, or that tree roots facilitate hydraulic lift of deep soil water, or groundwater, to depths within the rooting depth of both trees and grasses. Further research is needed to confirm the exact mechanism involved, and the consequences of this for groundwater and streamflow at landscape scales.

Phenolic composition of ten plants species used as ethnoveterinary medicines in Omusati and Kunene regions of Namibia.

The therapeutic benefits of phenolic compounds found in plants are well known. The purpose of this study was to determine the phenolic content of ten plant species used as ethnoveterinary treatments in Namibia's Omusati and Kunene regions. The plants of concern were Aloe esculenta, Fockea angustifolia, Boscia albitrunca, Combretum imberbe, Acacia nilotica, Colophospermum mopane, Acacia erioloba, Ziziphus mucronata, Ximenia americana, and Salvadora persica. An LC-MS approach was used to identify the compounds. To analyse high-resolution UPLC-UV/MS, a Waters Acquity ultra-performance liquid chromatograph (UPLC) with a photodiode array detector was connected to a Waters Synapt G2 quadrupole time-of-flight mass spectrometer (MS). The current study identified a total of 29 phenolic compounds. Flavonoids (epicatechin, (-)-Epigallocatechin, and rutin,) were the most abundant, followed by 2R, 3S-Piscidic acid. Methylisocitric acid was found in all species investigated, with the highest quantities in A. esculenta and X. americana leaf extracts. There were differences in composition and quantity of phenolic compounds in aerial and ground sections between species. The overall findings of the present study would act as a standard for subsequent investigations into the pharmacological potentials of plants species utilized as ethnoveterinary remedies. Priority should be given to isolating, purifying, and defining the active compounds responsible for these plants' activity.

Restoration of diversity and regeneration of woody species through area exclosure: the case of Maun International Airport in northern Botswana

Background and objectives: Deforested and degraded areas can be cheaply and conveniently restored through establishment of exclosures. An area exclosure excludes animals and humans from accessing an area to promote natural regeneration of plants and rehabilitate ecological condition of the area. The study was aimed at: (1) determining the diversity (species richness, diversity and evenness); (2) assessing the stand structure (densities); and (3) assessing regeneration status of woody species inside and outside exclosed Maun International Airport, northern Botswana. Methods: Vegetation sampling was conducted from April to May 2018. A total of 48 and 37 quadrats of 20 × 20 m were laid down at 50 m intervals along transect lines inside and outside Maun International Airport, respectively. Identity, number of all live individuals and height of all woody species were recorded in all the quadrats. The diversity of all woody species was analysed by using the Shannon Diversity Index (H’) and regeneration status of each woody species was assessed using frequency distribution of height class. Results: The diversity, evenness and species richness were significantly higher inside than outside Maun International Airport. Colophospermum mopane was the most abundant species both inside (75% of all woody species) and outside (96% of all woody species) Maun International Airport. More species showed more regeneration inside than outside Maun International Airport. The inside of Maun International Airport recorded more alien invasive woody species compared with the outside, owing to its original use as a residential area. The local communities might have introduced these species as ornamental trees. Conclusion: This study, while limited in scale, contributes to understanding of the role of exclosures in enhancing woody species richness, diversity and evenness as well as facilitating regeneration of woody species. Degraded woodlands and other similar ecosystems could be cheaply and conveniently restored through establishment of exclosures, but more research and monitoring are required to fully understand the processes and impacts.

Implementing Local Climate Change Adaptation Actions: The Role of Various Policy Instruments in Mopane (Colophospermum mopane) Woodlands, Northern Namibia

The impacts of climate change are severe in rural communities because of their proximity to forest ecosystems. Colophospermum mopane woodlands are vital in supporting the livelihood of the rural communities in the mopane woodlands while contributing to biodiversity conservation. There is limited research regarding implementing policy instruments for climate change adaptation in rural areas of the mopane woodlands in northern Namibia. This study aims to investigate this subject from the mopane woodlands’ point of view to understand the implementation of policy instruments for climate change adaptation in the mopane woodlands. We conducted an online survey focusing on multiple stakeholders, experts in different sectors, and local communities. Major challenges such as a limited general understanding of climate change, its impacts, dry conditions of Namibia, and lack of funds for adaptation measures hamper the implementation of policy instruments for climate change adaptation in mopane woodlands. Policymakers and relevant stakeholders should emphasize altering rural communities’ reliance on forest resources for their livelihood by improving their awareness of the impacts of climate change. Future research should evaluate climate change policy instruments’ framework and strategies in the context of forest ecosystems at the rural area level of Namibia.

Trends in elephant poaching in the Mid‐Zambezi Valley, Zimbabwe: Lessons learnt and future outlook

Trends in elephant poaching in the <scp>Mid‐Zambezi</scp> Valley, Zimbabwe: Lessons learnt and future outlook