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Newly germinated seedlings are vulnerable to biomass removal but usually have at least six months to grow before they are exposed to dry-season fires, a major disturbance in savannas. In contrast, plants are exposed to browsers from the time they germinate, making browsing potentially a very powerful bottleneck for establishing seedlings. Here we assess the resilience of seedlings of 10 savanna tree species to top-kill during the first 6 months of growth. Newly-germinated seeds from four dominant African genera from across the rainfall gradient were planted in a common garden experiment at the Wits Rural Facility and clipped at 1 cm when they were ~2, 3, 4, and 5 months old. Survival, growth, and key plant traits were monitored for the following 2.5 years. Seedlings from environments with high herbivory pressure survived top-kill at a younger age than those from low-herbivore environments, and more palatable genera had higher herbivore-tolerance. Most individuals that survived were able to recover lost biomass within 12 months, but the clipping treatment affected root mass fraction and branching patterns. Synthesis: The impact of early browsing as a demographic bottleneck can be predicted by integrating information on the probability of being browsed and the probability of surviving a browse event. Establishment limitation through early-browsing is an under-recognised constraint on savanna tree species distributions.

Linking people and places is essential for population-health-environment research. Yet, this data integration requires geographic coding such that information reflecting individuals or households can appropriately be connected with characteristics of their proximate environments. However, offering access to such geocoding greatly increases the risk of respondent identification and, therefore, holds the potential to breach confidentiality. In response, a variety of “geographic masking” techniques have been developed to introduce error into geographic coding and thereby reduce the likelihood of identification. We report findings from analyses of the error introduced by several masking techniques applied to data from the Agincourt Health and Socio-Demographic Surveillance System in rural South Africa. Using a vegetation index (Normalized Difference Vegetation Index (NDVI)) at the household scale, comparisons are made between the “true” NDVI values and those calculated after masking. We also examine the tradeoffs between accuracy and protecting respondent privacy. The exploration suggests that in this study setting and for NDVI, geomasking approaches that use buffers and account for population density produce the most accurate results. However, the exploration also clearly demonstrates the tradeoff between accuracy and privacy, with more accuracy resulting in a higher level of potential respondent identification. It is important to note that these analyses illustrate a process that should characterize spatially informed research but within which particular decisions must be shaped by the research setting and objectives. In the long run, we aim to provide insight into masking’s potential and perils to facilitate population-environment-health research.

Over the past decade, trophy hunting in Africa has seen increased public and scientific interest. Much of that attention has come from outside of Africa, with little emphasis on local views. We circulated an online survey through international networks to explore demographic and regional differences in opinion regards support for African trophy hunting, trophy import bans, and outside funding of conservation estates supported by hunting. We received ∼5700 responses and found that location, demography, and conservation background influenced opinion. African and North American respondents showed (significantly) more support for trophy hunting than respondents from Europe or other areas, as did respondents with conservation backgrounds. Unlike North Americans, Africans supported external subsidies of wildlife areas presently funded by hunting. Many factors affected opinions on African hunting, but respondent location played a major role. Realistic policy on African trophy hunting should thus integrate African perspectives, in particular those of rural communities.

Southern Africa is particularly sensitive to climate change, due to both ecological and socio-economic factors, with rural land users among the most vulnerable groups. The provision of information to support climate-relevant decision-making requires an understanding of the projected impacts of change and complex feedbacks within the local ecosystems, as well as local demands on ecosystem services. In this paper, we address the limitation of current approaches for developing management relevant socio-ecological information on the projected impacts of climate change and human activities. We emphasise the need for linking disciplines and approaches by expounding the methodology followed in our two consecutive projects. These projects combine disciplines and levels of measurements from the leaf level (ecophysiology) to the local landscape level (flux measurements) and from the local household level (socio-economic surveys) to the regional level (remote sensing), feeding into a variety of models at multiple scales. Interdisciplinary, multi-scaled, and integrated socio-ecological approaches, as proposed here, are needed to compliment reductionist and linear, scale-specific approaches. Decision support systems are used to integrate and communicate the data and models to the local decision-makers.

Savanna rangelands provide essential ecosystem services to people. Intense land-use and climate change may degrade ecosystems and influence the provision of ecosystem services. Complex dynamic vegetation models can simulate future vegetation and how vegetation may interact with land-use. Yet, identification of best-practice management directives in the face of climate change is challenging and requires consideration of socio-economic aspects. Here, we developed an economic model to describe the value of key ecosystem services, namely fuelwood harvesting and livestock, and coupled it with aDGVM, a vegetation model for tropical ecosystems. We used simulation optimization to identify land-use strategies that maximize economic value to stakeholders in the planning horizon until 2050, and compared it to realistic land-use intensities. We found that realistic intensities exceed optimal intensities, indicating the tragedy of the commons and external stress factors, prevalent in many rural savanna rangelands. We show that a reduction in fuelwood harvesting until 2050 allows vegetation to recover but that recovery is slow. We conclude that strong governance is important in rural savanna rangelands to ensure sustainable use of resources under future climate conditions. The coupled ecological-economic model can serve as tool to develop sustainable land-use strategies in complex socio-ecological systems globally.

Rural livelihoods in developing countries are disproportionately vulnerable to multiple shocks and stresses that exacerbate vulnerability, which can result in increased dependence on natural resources. Several studies have been conducted on the safety net role of natural resources, which lower the impact of negative shocks on rural livelihoods. However, the role of social capital as a safety net that can potentially lower natural resource use when households experience negative shocks has been less studied. We examined the role of natural resources and social capital as buffers against negative shocks to reduce vulnerability in rural livelihoods. Using five years of panel data from a rural population in South Africa, multilevel models were constructed to quantify the influence of shocks, social capital and household socio-demographic characterization on three dimensions of natural resource use, namely the number of types of natural resources used, the frequency of natural resource use, and the quantities of natural resources used. Results show that household experience of negative shocks was consistently associated with a significant increase in all dimensions of natural resource use. However, and unexpectedly, social capital did not significantly reduce natural resource use when households experienced shocks. This in no way discounts the role social capital plays in cushioning households post experience of shocks, but rather indicates that reliance on social and natural capital could be complementary rather than substitutable coping strategies post experience of shocks. Efforts to secure rural livelihoods and achieve sustainability should thus focus on building household physical capital to reduce dependency on natural resources in rural households.

Quantifying how multiple ecosystem services and functions are affected by different drivers of Global Change is challenging. Particularly in African savanna regions, highly integrated land-use activities created a landscape mosaic with flows of multiple resources between land use types. A framework is needed that quantifies the effects of climate change, management and policy interventions on ecosystem services that are most relevant for rural communities, such as provision of food, feed, carbon sequestration, nutrient cycling and natural pest control. In spite of progress made in ecosystem modelling, data availability and stakeholder interactions, these elements have neither been brought together in an integrated framework, nor evaluated in the context of real-world problems. Here, we propose and outline such framework as developed by a multi-disciplinary research network, the Southern African Limpopo Landscapes network (SALLnet). Components of the framework such as the crop model APSIM and the vegetation model aDGVM2 had already been parameterized and evaluated using data sets from savanna regions of eastern, western and southern Africa, and were fine-tuned using novel data sets from Limpopo. A prototype of an agent-based farm household model was developed using comprehensive farm survey information from the Limpopo Province of South Africa. A first test of the functionality of the integrated framework has been performed for alternative policy interventions on smallholder crop-livestock systems. We discuss the versatile applicability of the framework, with a focus on smallholder landscapes in the savanna regions of southern Africa that are considered hotspots of global change impacts.

Land-based income streams, which include the consumption and selling of crops, livestock and environmental products, are inherent in rural households’ livelihoods. However, the off-farm cash income stream – primarily composed of migrant labour remittances, social grants, and savings and loans – is increasing in importance in many regions. This case study of 590 households from Bushbuckridge, South Africa, analyses the economic value of each of these income streams at three points: what enters the household, what is used and what is sold. Two important findings emerge. First, dependence on offfarm cash incomes is far higher than previously suggested by case studies in the area and the benefits of employment accrue to those already better educated and wealthier. This suggests that shifts in offfarm opportunities will exacerbate already deep inequalities. Second, while environmental products and crops are important for direct use, they generate insignificant cash incomes from sales. This suggests a weakening of the direct links between the local ecosystem and this society, challenging traditional notions of African rurality being intrinsically land based. Significance: Off-farm incomes such as wage labour, remittances and social grants are almost the sole source of cash for households in the study area. Even when including non-monetary incomes such as harvested produce, foraged goods and livestock products, off-farm incomes still represent the overwhelmingly largest proportion of overall household income value. This highlights the fact that South African rural economies are not consistently or primarily land based, and indicates the necessity of rural development strategies that facilitate participation in local cash economies. Otherwise, such efforts will be unable to yield broad benefits and will, instead, simply enrich those who are already better off.

This Commentary is a response to a Commentary published in the May/June 2020 issue: Nattrass N. Why are black South African students less likely to consider studying biological sciences? S Afr J Sci. 2020;116(5/6), Art. #7864, 2 pages. https://doi.org/10.17159/sajs.2020/7864 Responses to the Commentary in the May/June 2020 issue have been published collectively in a special issue of Volume 116.

On the background of increasing welfare and continued population growth, there is an ever-increasing pressure on land and other natural resources in many parts of the world. The situation is, however, particularly severe in the drylands of Sub-Saharan Africa. Southern African landscapes, composed of arable lands, tree orchards and rangelands, provide a range of important ecosystem functions. These functions are increasingly threatened by land use changes through competing claims on land by agriculture, tourism, mining and other sectors, and by environmental change, namely climate change and soil degradation. Among others, climate models project that drought risk in the region will increase considerably. Based on comprehensive data sets originating from previous groundwork by several collaborative projects on the functioning of these ecosystems, a number of biophysical and bio-economic models have been developed and evaluated. In the framework of the South African Limpopo Landscapes network (SALLnet) we have now refined and tailored these models for combined use for the assessment of changes in multiple functions of the prevailing agroecosystems when affected by alternative climate and land management scenarios - from field to regional scale. We apply vegetation models (such as aDGVM), crop models (such as APSIM) and integrative farm level models (e.g. agent-based) for different farming systems in conjunction with geo-referenced databases. Model outputs are combined to assess the impact of management x environment interactions on various ecosystem functions. Of special interest in our study are the ecosystem services related to the provision of food, feed and fuel, soil and water conservation, as well as recycling and restoring carbon and nutrients in soil. To illustrate how the combination of various modelling components can work in assessing management intervention effects under different environmental conditions on landscape level ecosystem services, a case study was defined in Limpopo province, South Africa. We investigated effects of current management practices and an intensification scenario over a longer period of years on soil organic carbon change under rangeland and arable land, potential erosion, productive water use, biomass production, monthly feed gaps, and rangeland habitat quality. Tentative results showed that sustainable intensification closed the livestock feed gap, but further reduced soil organic carbon. More generally, coupling the output of vegetation and crop models regionally calibrated with sound ground/ experimental data appears promising to provide meaningful insights into the highly complex interconnections of different ecosystem services at a landscape level.

Objectives: (1) To evaluate how ecosystem services may be utilized to either reinforce or fracture the planning and development practices that emerged from segregation and economic exclusion; (2) To survey the current state of ecosystem service assessments and synthesize a growing number of recommendations from the literature for renovating ecosystem service analyses. Methods: Utilizing current maps of ecosystem service distribution in Bushbuckridge Local Municipality, South Africa, we considered how a democratized process of assessing ecosystem services will produce a more nuanced representation of diverse values in society and capture heterogeneity in ecosystem structure and function. Results: We propose interventions for assessing ecosystem services that are inclusive of a broad range of stakeholders’ values and result in actual quantification of social and ecological processes. We demonstrate how to operationalize a pluralistic framework for ecosystem service assessments. Conclusion: A democratized approach to ecosystem service assessments is a reimagined path to rescuing a poorly implemented concept and designing and managing future social-ecological systems that benefit people and support ecosystem integrity. It is the responsibility of scientists who do ecosystem services research to embrace more complex, pluralistic frameworks so that sound and inclusive scientific information is utilized in decision-making.

The sustainability of protected areas is dependent on societal support. Protected area relevance (meaning and value) to society is based on vested interest grown through conservation related benefit accrual that outweighs costs. Protected areas generally don’t report on their total societal impact in part due to a lack of an appropriate framework that accounts simultaneously for positive and negative, tangible and intangible components. We develop a framework and pathway that (1) includes ecosystem dis-services provided by protected areas, and (2) provides a tool for protected area managers to report on benefit sharing as a whole towards managing cost-benefit trade-offs. Ecosystem services and products from Kruger National Park were classified into themes, followed by a quantitative inventory of cost/benefit processes for the KNP. We demonstrate the skewed nature of costs versus benefits, with most beneficiaries living far from the park. Most local residents receive few benefits and are often recipients of costs. The framework highlights the need to understand the impact of benefit sharing on human well-being; the lack of an understanding of the outputs and outcomes from direct ecosystem service flows from parks; and the need for an understanding of the links between benefit accrual and conservation-related outcomes.

A range of social and economic factors impact tree species, such as Sclerocarya birrea subsp. caffra (marula), which provide livelihood sustenance for local communities in the savanna woodlands of southern Africa. As an ecologically important savanna species, valued both culturally and economically, it is imperative to understand if resource use is sustainable. Population stability can be understood by comparing tree density and size-class distribution (SCD) profiles across land-use types (homestead yards, fields and rangelands) in non-conservation savanna social-ecological systems. Marula tree population data were gathered in rangeland transects and randomly selected fields and yards from four human settlements in the Bushbuckridge municipality of north-eastern South Africa. Total density was lowest in fields (mean ± SE = 7.4 ± 0.7 trees/ha) and highest in homestead yards (mean ± SE = 25.7 ± 4.1 trees/ha). Social data revealed that elevated seedling and sapling population densities in yards is linked to discarded kernels from marula beer making. Total densities increased in yards over a 15-year period but declined in rangelands, with female densities remaining almost constant across land-use types over this period. This is an important finding as it is a strong indication of socially-mediated population structure changes, confirming that combined cultural and economic value can lead to examples of species conservation. In this case, the prioritization of female trees as the distinguished fruit producers. SCD revealed weak recruitment in fields and rangelands. Diminished regeneration, combined with overharvesting for fuelwood in rangelands and felling trees in yards, is likely to negatively impact population stability in the long-term. Understanding resource conservation and degradation in the context of important non-timber forest products (NTFPs) is a key knowledge challenge, with this study serving as an updated inventory benchmark for marula populations in the area. Important lessons learned here can be applied to other social-ecological contexts where a key natural resource is responsible for sustaining livelihoods.

Smallholder production is a significant contributor to rural livelihoods and rural economies in much of the developing world. Yet, there is evidence of increasing disengagement in some regions, including southern Africa. However, there has been little consideration of the rates and the livelihood, ecological and policy implications of such. In this paper we examine previous studies on rates of deactivation of crop fields by smallholders in the communal areas of South Africa, supported by repeat photo images and case study material. Together these various methods show that it is a widespread phenomenon occurring at variable rates. Over short periods deactivation of crop fields can be balanced through some reactivation or intensification of homegardens. But over longer periods there is a net decline in the area of fields cultivated in many areas, with corresponding increases in the area of fallow land which, through time, may undergo changes towards more natural vegetation. We review the drivers of this deactivation of field cropping, and then contemplate the possible socio-economic and ecological implications at local and national scales. We show that there are numerous and profound implications that require greater understanding and policy responses.

A mopane worm (Imbrasia belina) harvesting project in the Kruger National Park (KNP) was used as a case study to test whether conservation related benefit sharing has a net positive impact on multiple dimensions of human well-being. Furthermore, the study assessed whether and to what degree, sharing such benefits influenced local perceptions of conservation, a requirement for the sustainability of protected areas across the globe. The project involved 263 people from 16 villages, adjacent to the KNP, harvesting 4,688 L worms contributing the equivalent of over half of the average household income during the months of harvest. Despite paying for transport, the participants gained from the experience; instilling the feeling that the park is opening up to them, and as a result seeing the park differently. For most participants the project provided them their first opportunity to visit the park, and participants perceived this to have further contributed positively to their wellbeing as a result of the associated learning experiences. Furthermore, participants enjoyed meeting and getting to know the park staff, with these new social connections contributing positively to social wellbeing. Respondents perceived their relationship with the park to be positive and expressed hope for building on this in the future. We conclude that measuring the multiple dimensions of human wellbeing in impact assessments is beneficial, and that the social connections that are built between neighbours, protected area staff and the natural and cultural resources within protected areas as a result of such projects can have mutually beneficial outcomes both for people and conservation.

Drivers of soil organic carbon (SOC) dynamics involve a combination of edaphic, human, and climatic factors that influence and determine SOC distribution across the landscape. High-resolution maps of key indicators of ecosystem health can enable assessments of these drivers and aid in critical management decisions. This study used a systematic field-based approach coupled with statistical modeling and remote sensing to develop accurate, high-resolution maps of key indicators of ecosystem health across savanna ecosystems in South Africa. Two 100-km landscapes in Bushbuckridge Local Municipality were surveyed, and 320 composite topsoil samples were collected. Mid-infrared spectroscopy was used to predict soil properties, with good performance for all models and root mean squared error of prediction (RMSEP) values of 1.3, 0.2, 5, and 3.6 for SOC, pH, sand, and clay, respectively. Validation results for the mapping of soil erosion prevalence and herbaceous cover using RapidEye imagery at 5-m spatial resolution showed good model performance with area under the curve values of 0.80 and 0.86, respectively. The overall (out-of-bag) random forest model performance for mapping of soil properties, reported using , was 0.8, 0.77, and 0.82 for SOC, pH, and sand, respectively. Calibration model performance was good, with RMSEP values of 2.6 g kg for SOC, 0.2 for pH, and 6% for sand content. Strong gradients of increasing SOC and pH corresponded with decreasing sand content between the study sites. Although both sites had low SOC overall, important driving factors of SOC dynamics included soil texture, soil erosion prevalence, and climate. These data will inform strategic land management decisions focused particularly on improving ecosystem conditions.

Much of the international commons literature reveals a decreased functioning of local traditional institutions that regulate natural resource harvesting. In South Africa, it is believed that the creation of new democratic structures at the end of Apartheid has contributed significantly to the deterioration in traditional resource regulation and this in turn has led to the extensive resource degradation seen in parts of the country. Many of these assertions, though, remain anecdotal in nature. Given the high reliance by rural households on natural resources, and the serious negative implications that over-use has on livelihood security, understanding how well or poorly such commons are regulated is key to ensuring the sustainability of such resource-dependent populations. The aim of this study was therefore to examine systems of resource governance, focusing specifically on firewood, and to determine the roles of traditional and democratically elected community leaders in six rural villages spanning two chieftaincies in Bushbuckridge, South Africa. In each study village, five local leaders were interviewed and five community focus groups were conducted. Results indicate that most parties still regard the Chief as the ultimate authority for regulating firewood harvesting. However, overall firewood management appears weak, at best, across the region. Although some authors attribute this to community confusion over the roles of local leaders in a new democracy, we provide evidence that other socio-political factors, including political expediency, may be driving the increasingly relaxed implementation of these firewood management systems. With resource dependence remaining a vital contributor to livelihood security across the developing world and with many rural communities facing increasing strain under local resource depletion, these findings shed new light on the complex social dynamics underlying the widely reported weakening of traditional institutions in South Africa. In so doing, it offers insights into local firewood governance that can be used to combat these challenges and thereby reduce regional social and ecological vulnerability being experienced in communal landscapes across the region.

Questions related to how we practice sustainability science remain salient in the face of the failure to achieve broad-scale sustainability objectives. Transdisciplinarity is an essential part of sustainability science. Transdisciplinary conceptual scholarship has been more prevalent than empirical scholarship or applications, especially in developing world contexts. In a single case study of a multiyear project addressing water security issues in HaMakuya, South Africa, we used a framework for assessing transdisciplinary objectives to facilitate more systematic learning for those who practice sustainability science. We found that defining the problem and assembling our team were easier than the co-creation of solution-oriented knowledge and the reintegration and application of this new knowledge. Our singular case study speaks to the potential challenges related to building relationships and co-creating knowledge in an epistemologically diverse setting. Other case studies appear to have negotiated these issues in developing country contexts, and this leaves room further investigation for how to practice transdisciplinarity under these conditions.

This paper examines the impact of agriculture-related shocks on consumption patterns of rural farming households using 3 years of data from South Africa. We make two key observations. First, agriculture-related shocks reduce households’ consumption. Second, natural resources and informal social capital somewhat counteract this reduction and sustain dietary requirements. In general, our findings suggest the promotion of informal social capital and natural resources as they are cheaper and more accessible coping strategies, in comparison to, for example, insurance, which remains unaffordable in most rural parts of sub-Saharan Africa. However, a lingering concern centres on the sustainability of these less conventional adaptation strategies.

Ungulate herbivory, interacting with human activities such as tree cutting, can change vegetation structure by reducing tree growth or even increasing tree mortality. There is limited information about how browsing that occurs subsequent to coppicing affects regrowth of resprouting trees, with available data focusing on mature trees and seedlings. To address this knowledge gap, we studied the effect of browsing on the coppice response of resprouting Terminalia sericea trees in a semi-arid savanna in South Africa. The coppice response of browsed trees was compared with that of unbrowsed trees for 12 months after excluding all browsing from study trees. Shoot production was initially higher for browsed coppiced trees, but this effect diminished with time. Resprout shoot diameter and shoot length remained higher throughout the study for unbrowsed coppiced trees. Leaf stomatal conductance and leaf expansion were initially higher for browsed coppiced trees, with no significant differences observed as the wet season progressed. Foliar nitrogen and phosphorus levels were higher in browsed coppiced trees. These tree responses suggest that exposing resprouting trees to browsing initially induces a quick response in terms of shoot production, in order to recover lost biomass, but this growth declines as the growing season progresses.

There is limited information about the factors that affect phenology of coppicing trees. This study examined the effects of water and nutrient additions on the phenology of coppicing Terminalia sericea trees in a semi-arid savanna in South Africa. Cut trees were exposed to different levels of water and nutrient (nitrogen and phosphorus) supplementations over a period of two years. Phenological stages monitored fortnightly included leaf bud presence, leaf presence and fruit production. Leaf presence followed a similar distribution to bud presence, peaking during the wet season (November–April), with the low water and high nutrient additions having the highest significant effect. Change in leaf color from the typical silvery green to yellow was delayed to later in the wet season, while higher leaf numbers were recorded during the wet seasons for trees supplemented with water and nutrients. Results indicate that the increase in water and nutrient availability has direct consequences for extending the growing season of resprouting trees. This extension has positive effects on increasing the photosynthetically active period, thus potentially increasing the carbon gain and growth of trees. Although generally low throughout the study in all treatments, fruit presence was mainly in supplemented trees.

Scholarly understanding of human migration’s environmental dimensions has greatly advanced in the past several years, motivated in large part by public and policy dialogue around “climate migrants”. The research presented here advances current demographic scholarship both through its substantive interpretations and conclusions, as well as its methodological approach. We examine temporary rural South African outmigration as related to household-level availability of proximate natural resources. Such “natural capital” is central to livelihoods in the region, both for sustenance and as materials for market-bound products. The results demonstrate that the association between local environmental resource availability and outmigration is, in general, positive: households with higher levels of proximate natural capital are more likely to engage in temporary migration. In this way, the general findings support the “environmental surplus” hypothesis that resource security provides a foundation from which households can invest in migration as a livelihood strategy. Such insight stands in contrast to popular dialogue, which tends to view migration as a last resort undertaken only by the most vulnerable households. As another important insight, our findings demonstrate important spatial variation, complicating attempts to generalize migration-environment findings across spatial scales. In our rural South African study site, the positive association between migration and proximate resources is actually highly localized, varying from strongly positive in some villages to strongly negative in others. We explore the socio-demographic factors underlying this “operational scale sensitivity”. The cross-scale methodologies applied here offer nuance unavailable within more commonly used global regression models, although also introducing complexity that complicates story-telling and inhibits generalizability., Comparative Population Studies, Vol 42 (2017)

BackgroundMalaria elimination is on global agendas following successful transmission reductions. Nevertheless moving from low to zero transmission is challenging. South Africa has an elimination target of 2018, which may or may not be realised in its hypoendemic areas.MethodsThe Agincourt Health and Demographic Surveillance System has monitored population health in north-eastern South Africa since 1992. Malaria deaths were analysed against individual factors, socioeconomic status, labour migration and weather over a 21-year period, eliciting trends over time and associations with covariates.ResultsOf 13 251 registered deaths over 1.58 million person-years, 1.2% were attributed to malaria. Malaria mortality rates increased from 1992 to 2013, while mean daily maximum temperature rose by 1.5 °C. Travel to endemic Mozambique became easier, and malaria mortality increased in higher socioeconomic groups. Overall, malaria mortality was significantly associated with age, socioeconomic status, labour migration and employment, yearly rainfall and higher rainfall/temperature shortly before death.ConclusionsMalaria persists as a small but important cause of death in this semi-rural South African population. Detailed longitudinal population data were crucial for these analyses. The findings highlight practical political, socioeconomic and environmental difficulties that may also be encountered elsewhere in moving from low-transmission scenarios to malaria elimination.

Although exposure to multiple cutting cycles reduces stored reserves, shoot diameter and shoot length, it, however, increases shoot production per resprouting stump and foliar nitrogen. In disturbance-prone environments with fluctuating seasonal rainfall such as savannas, the repeated cutting of the same trees eventually results in a possible decline in tree abundance. The effects of subjecting Terminalia sericea trees to one, two and multiple (eight) cutting events over a period of 2 years on coppice response were investigated in a savanna woodland in South Africa. Resprout shoot diameter, shoot length and the total cumulative diameter were lower in trees exposed to a high number of cutting events compared to trees exposed to one cutting event. Increasing the number of cutting events significantly reduced stem total non-structural carbohydrate levels in trees indicating a depletion of stored reserves. Foliar carbon content remained largely the same, while leaf nitrogen and phosphorus concentrations significantly increased with each cutting event, relative to uncut trees. Results indicate that trees cut once had not replenished depleted carbohydrate reserves even after a period of 18 months during which no cutting took place. Sustainable utilization of this tree species must allow for at least more than 18 months of undisturbed growth between harvests to allow for the replenishing of reserves.

Socioecological theory, developed through the study of urban environments, has recently led to a proliferation of research focusing on comparative analyses of cities. This research emphasis has been concentrated in the more developed countries of the Northern Hemisphere (often referred to as the “Global North”), yet urbanization is now occurring mostly in the developing world, with the fastest rates of growth in sub-Saharan Africa. Countries like South Africa are experiencing a variety of land-cover changes that may challenge current assumptions about the differences between urban and rural environments and about the connectivity of these dynamic socioecological systems. Furthermore, questions concerning ecosystem services, landscape preferences, and conservation – when analyzed through rural livelihood frameworks – may provide insights into the social and ecological resilience of human settlements. Increasing research on urban development processes occurring in Africa, and on patterns of kinship and migration in the less developed countries of the “Global South”, will advance a more comprehensive worldview of how future urbanization will influence the progress of sustainable societies.

Rural households across the globe engage in both migration and natural resource use as components of livelihood strategies designed to meet household needs. Yet, migration scholars have only recently begun to regularly integrate environmental factors into empirical modelling efforts. To examine the migration-environment association in rural South Africa, we use vegetation measures derived from satellite imagery combined with detailed demographic data from over 9000 households at the Agincourt Health and Demographic Surveillance Site. Results reveal that household-level temporary migration is associated with higher levels of local natural capital, although no such association exists for permanent migration. Further, more advantaged households exhibit a stronger association between migration-environment, in-line with the 'environmental capital' hypothesis, suggesting that natural resource availability can facilitate household income diversification. We argue that a focus on migration's environmental aspects is especially timely in the contemporary era of climate change and that natural capital availability and variability represent critical pieces of the empirical migration puzzle, especially regarding cyclical livelihood migration.

Accurate measurement of household food security is essential to generate adequate information on the proportion of households experiencing food insecurity, especially in areas or regions vulnerable to food shortages and famine. This manuscript offers a methodological examination of three commonly used indicators of household food security – experience of hunger, dietary diversity, and coping strategies. Making use of data from the Agincourt Health and Demographic Surveillance Site in rural South Africa, we examine the association between the indicators themselves to improve understanding of the different insight offered by each food security “lens.” We also examine how the choice of indicator shapes the profile of vulnerable households, with results suggesting that dietary diversity scores may not adequately capture broader food insecurity. Concluding discussion explores programmatic and policy implications as related to methodological choices.

Energy security is central to achieving sustainable development and reducing poverty worldwide. Over 70% of the population of Sub-Saharan Africa, mostly in the rural areas, depend on wood fuel, as firewood or charcoal, to meet their primary domestic energy requirements. This dependence is projected to increase with population growth in the intermediate future, regardless of the implementation of rural electrification programmes.. Fuelwood shortages occur at the localised village level and are a chronic landscape syndrome, becoming more severe over time, with increasing population pressures and competing land-uses. In the South African context, the provision of electricity to rural households at subsidised rates would be expected to provide a viable alternative to fuelwood under conditions of scarcity. This paper compares the fuelwood consumption strategies of households in a fuelwood-scarce environment against those in fuelwood-abundant environment in order to illustrate the inelastic nature of the demand for fuelwood in rural communities, even in the face of severely depleted wood stocks. We seek to understand the mechanisms that households implement to ensure household fuelwood/energy security and how these responses aggregate at the landscape level to shape landscape dynamics. This will aid better planning of intervention policies in the future.

The ability of a woody plant to coppice and remain vigorous largely depends on the severity of disturbances, resource availability and the mobilisation of stored reserves. There is limited information about the role played by resource limitation on the recovery of cut trees. This study investigated the effects of water and nutrient supplementation on coppice growth responses of resprouting cut trees in a semi-arid savannah in South Africa. Cut trees were exposed to different levels of water and nutrient (nitrogen and phosphorus) supplementation over a period of 2 years in a factorial experimental design. We hypothesised that adding water and nutrients would result in an increased coppice growth response and replenishment of stored structural reserves. Adding water and nutrients significantly increased shoot diameter, shoot length and resprouting ratio for the initial 12 months after cutting but not stored structural reserves. Such a response pattern suggests that the initial growth of resprouting shoots may be strongly resource-limited, while resources are concentrated on supporting fewer resprouting shoots compared to a higher number.Conservation implications: If practicing rotational tree harvesting, trees resprouting in resource-poor locations need a longer resting period to recover stored reserves and to also recover lost height after cutting.

SUMMARYFuelwood is the dominant source of energy used by most rural households in southern Africa to meet daily domestic energy requirements. Due to limited financial resources, most rural households are unable to make the transition to electricity thus they remain dependant on the woodlands surrounding their settlements as a source of cheap energy. Unsustainable fuelwood harvesting due to increasing demand as a result of growing human populations may result in environmental degradation particularly in the high-density, communal savannah woodlands of South Africa. Evaluating the sustainability of current fuelwood harvesting patterns requires an understanding of the environmental impacts of past logging practices to establish patterns of woodland degradation. This study evaluates impacts of fuelwood harvesting from 1992–2009 on the woodland structure and species composition surrounding two rural villages located within the Kruger to Canyons Biosphere Reserve (Mpumalanga Province, South Africa). Both villages (Welverdiend and Athol) were of similar spatial extent and exhibited similar socioeconomic characteristics. The total wood stock in the communal woodlands of both villages declined overall (with greater losses seen in Welverdiend) and, in Welverdiend, there were also changes in the woodland structure and species diversity of the species commonly harvested for fuelwood over this period. The woodlands in Welverdiend have become degraded and no longer produce fuelwood of preferred species and stem size in sufficient quantity or quality. The absence of similar negative impacts in Athol suggests more sustainable harvesting regimes exist there because of the lower human population and lower fuelwood extraction pressure. The Welverdiend community has annexed neighbouring unoccupied private land in a social response to fuelwood scarcity. Athol residents behaved similarly during drought periods. The potential for future conflict with neighbouring conservation areas within the Kruger to Canyons Biosphere is high if current land uses and fuelwood extraction patterns are maintained.