14 research outputs found
The self-reported human health effects associated with heat exposure in Agincourt sub-district of South Africa
DATA AVAILABILITY : Qualitative data sets are restricted and not publicly available. Due to confidentiality agreements, supporting data can only be made available to bona fide researchers subject to a non-disclosure agreement. Details of the data and how to request access are available from A.E. Manyuchi at Global Change Institute of The University of the Witwatersrand.Exposure to heat and heatwaves are associated with mortality and may amplify morbidities. In a climate change context, projections suggest temperatures will likely rise in the foreseeable future. Our paper assesses the current knowledge on human health effects of heat exposure and gathered local knowledge of heat-health effects in a rural area of the Agincourt sub-district of South Africa. Existing, peer-reviewed published literature on heat effects on human health as well as heat-health indicators was reviewed. Interviews and structured observations to collect data on heat effects on human health in Agincourt sub-district were conducted. The Lancet Countdown heat-related indicators were applied as a framework against which to discuss our findings. A total of 93 participants who lived in Agincourt sub-district for 5 years and more were interviewed. Participants reported that temperatures, especially summertime temperatures, had been rising over the past years. Health effects of heat were deemed more apparent in relation to morbidity. Heatwaves were not easily comprehensible as singular âeventsâ, and their effects were poorly understood. The population groups disproportionately affected by heat included infants, the elderly, those living with disability and outdoor workers. High ambient temperatures were deemed to be associated with reduced labour productivity of outdoor workers. Community-level perceptions of heat impacts on health were mainly related to illnesses and diseases, with no understanding of mortality risk. Future health awareness campaigns that encompass the full range of heat-health impacts are essential to reduce vulnerability, morbidity, and mortality. Our study provided location-specific, qualitative, and indicator-aligned data for a geographic area expected to undergo significant heat stress in the future. The study findings have significant research, policy, and practice implications in similar resource-limited settings.The Global Change Institute (GCI) of the University of the Witwatersrand.https://www.nature.com/palcommshj2023Geography, Geoinformatics and Meteorolog
Systems approach to climate services for health
Climate change and variability remain a pressing global challenge directly and indirectly affecting human health. This has increased the demand for usable climate information for adaptation to climate related health challenges and for building effective response strategies. Climate services for health can help to enhance human well-being and in extreme cases can save human lives by reducing morbidity and mortality. Very little has been done and understood about how we can enhance climate services for health. The main aim of this perspective article is to bring empirical evidence, conceptual clarity and interdisciplinary approaches to policy makers and practitioners dealing with this crucial issue. The article explores the application of a holistic, broadly termed âsystemsâ approach to climate services for health in the context of adaptation and resilience. It uses illustrative examples from Ethiopia, Bhutan and Germany to demonstrate and elaborate the application and merits of the systems approach to emerging climate services for health. The systems approach improves conceptual thinking about climate services for health. In addition, it is a valuable analytical framework that unifies the diverse stakeholders involved in health adaptation and resilience planning, interventions and policy making. This perspective article fills in the existing gaps in scientific literature on the subject and enhances conceptualisation of climate services for health. It makes suggestions to improve understanding of climate services for health.https://www.elsevier.com/locate/cliserhj2022Geography, Geoinformatics and Meteorolog
Contrasting capabilities of two ungulate species to cope with extremes of aridity
Southern Africa is expected to experience increased frequency and intensity of droughts through
climate change, which will adversely affect mammalian herbivores. Using bio-loggers, we tested
the expectation that wildebeest (Connochaetes taurinus), a grazer with high water-dependence,
would be more sensitive to drought conditions than the arid-adapted gemsbok (Oryx gazella
gazella). The study, conducted in the Kalahari, encompassed two hot-dry seasons with similar
ambient temperatures but differing rainfall patterns during the preceding wet season. In the drier
year both ungulates selected similar cooler microclimates, but wildebeest travelled larger distances
than gemsbok, presumably in search of water. Body temperatures in both species reached lower
daily minimums and higher daily maximums in the drier season but daily fluctuations were wider
in wildebeest than in gemsbok. Lower daily minimum body temperatures displayed by wildebeest
suggest that wildebeest were under greater nutritional stress than gemsbok. Moving large distances
when water is scarce may have compromised the energy balance of the water dependent wildebeest,
a trade-off likely to be exacerbated with future climate change.DATA AVAILABILITY : The data that support the findings of this study are available in AfriMove repository, www.afrimove.org.The National Research Foundation of South Africa, the Centre for African Ecology; and University of the Witwatersrand Faculty of Science Research Committee.https://www.nature.com/srepam2022Zoology and Entomolog
Impacts of climate change on health and wellbeing in South Africa
Supplementary Materials: File S1, Protocol for systematic review of Climate Change research in South Africa.Given its associated burden of disease, climate change in South Africa could be reframed as
predominately a health issue, one necessitating an urgent health-sector response. The growing impact
of climate change has major implications for South Africa, especially for the numerous vulnerable
groups in the country. We systematically reviewed the literature by searching PubMed and Web
of Science. Of the 820 papers screened, 34 were identified that assessed the impacts of climate
change on health in the country. Most papers covered effects of heat on health or on infectious
diseases (20/34; 59%). We found that extreme weather events are the most noticeable effects to date,
especially droughts in theWestern Cape, but rises in vector-borne diseases are gaining prominence.
Climate aberration is also linked in myriad ways with outbreaks of food and waterborne diseases,
and possibly with the recent Listeria epidemic. The potential impacts of climate change on mental
health may compound the multiple social stressors that already beset the populace. Climate change
heightens the pre-existing vulnerabilities of women, fishing communities, rural subsistence farmers
and those living in informal settlements. Further gender disparities, eco-migration and social
disruptions may undermine the preventionâbut also treatmentâof HIV. Our findings suggest that
focused research and effective use of surveillance data are required to monitor climate changeâs
impacts; traditional strengths of the countryâs health sector. The health sector, hitherto a fringe
player, should assume a greater leadership role in promoting policies that protect the publicâs health,
address inequities and advance the countryâs commitments to climate change accords.http://www.mdpi.com/journal/ijerpham2018Geography, Geoinformatics and Meteorolog
Extreme heat events, high ambient temperatures and human morbidity and mortality in Africa : a systematic review
Temperature extremes vary across Africa. A continent-wide examination of the impacts of heat on
health in Africa, and a synthesis of Africa-informed evidence is, however, lacking. A systematic review
of articles published in peer-reviewed journals between January 1992 and April 2019 was conducted.
To be eligible, articles had to be Africa-specific, in English, and focused on how heatwaves and high
ambient temperatures affect morbidity and mortality. A secondary systematic analysis on policies and
interventions comprising 17 studies was also conducted, and the findings synthesised together with those
of the 20 primary studies. Eleven studies showed that high ambient temperatures and heat waves are
linked with increased mortality rates in Africa. These linkages are characterised by complex, linear and
non-linear (J or U) relationships. Eight of the nine primary studies of morbidity outcome reported that an
increase in temperature was accompanied by raised disease incidence. Children and the elderly were the
population groups most vulnerable to extreme heat exposure. Location-specific interventions and policy
suggestions include developing early warning systems, creating heat-health plans, changing housing
conditions and implementing heat-health awareness campaigns. In summary, this review demonstrates
that, while heat-health relationships in Africa are complex, extreme temperatures are associated with high
mortality and morbidity, especially amongst vulnerable populations. As temperatures increase across
Africa, there is an urgent need to develop heat-health plans and implement interventions. Future studies
must document intervention effectiveness and quantify the costs of action and inaction on extreme heatrelated mortality and morbidity.
SIGNIFICANCE :
⢠Empirical evidence shows that the relationship between heat and human health is complex in the African
context. This complexity has implications for the development of interventions and policies for heathealth on the continent.
⢠This review is important for African policymakers, practitioners and others who support Africaâs
adaptation to climate change. Through this review, a compendium of Africa-specific and relevant empirical
information is aggregated and made readily available to various interested and affected parties.http://www.sajs.co.zahj2022Geography, Geoinformatics and Meteorolog
Synergistic effects of climate and land-use change on representation of African bats in priority conservation areas
Bats are considered important bioindicators and deliver key ecosystem services to humans. However, it is not clear how the individual and combined effects of climate change and land-use change will affect their conservation in the future. We used a spatial conservation prioritization framework to determine future shifts in the priority areas for the conservation of 169 bat species under projected climate and land-use change scenarios across Africa. Specifically, we modelled species distribution models under four different climate change scenarios at the 2050 horizon. We used land-use change scenarios within the spatial conservation prioritization framework to assess habitat quality in areas where bats may shift their distributions. Overall, batsâ representation within already existing protected areas in Africa was low (âź5% of their suitable habitat in protected areas which cover âź7% of Africa). Accounting for future land-use change resulted in the largest shift in spatial priority areas for conservation actions, and species representation within priority areas for conservation actions decreased by âź9%. A large proportion of spatial conservation priorities will shift from forested areas with little disturbance under present conditions to agricultural areas in the future. Planning land use to reduce impacts on bats in priority areas outside protected areas where bats will be shifting their ranges in the future is crucial to enhance their conservation and maintain the important ecosystem services they provide to humans.http://www.elsevier.com/locate/ecolind2017-10-31hb2016Centre for Wildlife ManagementMammal Research InstituteZoology and Entomolog
Fuelwood extraction intensity drives compensatory regrowth in African savanna communal lands
Woody biomass remains the primary energy source for domestic use in the developing world, raising concerns about woodland sustainability. Yet woodland regenerative capacity and the adaptive response of harvesters to localised fuelwood shortages are often underestimated or unaccounted for in fuelwood supplyâdemand models. Here, we explore the rates and patterns of heightâspecific woody vegetation structural dynamics in three communal lands in a semiarid savanna in South Africa. Using repeat, airborne light detection and ranging, we measured heightâspecific change in woody vegetation structure, and the relative influence of geology, fire, and ease of access to fuelwood. Monitoring 634,284 trees canopies over 4 years revealed high compensatory growth, particularly in the high wood extraction communal land: 34.1% of trees increased in height >1 m. Vegetation structural patterns were associated with ease of access to the communal land but were mediated by wood extraction intensity. In these communal lands, vegetation structural dynamics show rapid woody thickening as a response to repeat harvesting. However, loss of height in vegetation structure did not follow a gradient of wood extraction intensity. We propose a conceptual framework to better understand change in vegetation structural metrics and the paradoxical phenomenon of high growth in high wood extraction scenarios. We also show coadaptive responses of humans and woody vegetation to fuelwood harvesting in humanâenvironment systems through patterns of regrowth response relative to ease of access to fuelwood resources.LiDAR data collection was funded by the Andrew Mellon Foundation, the Council for Scientific and Industrial Research (CSIR) Strategic Research Panel and the Department of Science and Technology (DST). The CAO has been made possible by grants and donations from the Avatar Alliance Foundation, Margaret A. Cargill Foundation, David and Lucile Packard Foundation, Gordon and Betty Moore Foundation, Grantham Foundation for the Protection of the Environment, W. M. Keck Foundation, John D. and Catherine T. MacArthur Foundation, Andrew Mellon Foundation, Mary Anne Nyburg Baker and G. Leonard Baker Jr, and William R. Hearst III. B. F. N. E. is supported by the Exxaro Chairman's Fund. P. J. M. is funded by the DST/NRF Centre of Excellence in Tree Health Biotechnology and an NRF Innovation Scholarship (grant UID: 95030).http://onlinelibrary.wiley.com/journal/10.1002/(ISSN)1099-145X2020-01-30hj2018Geography, Geoinformatics and Meteorolog
Humans and elephants as treefall drivers in African savannas
Humans have played a major role in altering savanna structure and function, and growing land-use pressure will only increase their influence on woody cover. Yet humans are often overlooked as ecological components. Both humans and the African elephant Loxodonta africana alter woody vegetation in savannas through removal of large trees and activities that may increase shrub cover. Interactive effects of both humans and elephants with fire may also alter vegetation structure and composition. Here we capitalize on a macroscale experimental opportunity â brought about by the juxtaposition of an elephant-mediated landscape, human-utilized communal harvesting lands and a nature reserve fenced off from both humans and elephants â to investigate the influence of humans and elephants on height-specific treefall dynamics. We surveyed 6812 ha using repeat, airborne high resolution Light Detection and Ranging (LiDAR) to track the fate of 453 685 tree canopies over two years. Human-mediated biennial treefall rates were 2â3.5 fold higher than the background treefall rate of 1.5% treefall haâ1, while elephant-mediated treefall rates were 5 times higher at 7.6% treefall haâ1 than the control site. Model predictors of treefall revealed that human or elephant presence was the most important variable, followed by the interaction between geology and fire frequency. Treefall patterns were spatially heterogeneous with elephant-driven treefall associated with geology and surface water, while human patterns were related to perceived ease of access to wood harvesting areas and settlement expansion. Our results show humans and elephants utilize all height classes of woody vegetation, and that large tree shortages in a heavily utilized communal land has transferred treefall occurrence to shorter vegetation. Elephant- and human-dominated landscapes are tied to interactive effects that may hinder tree seedling survival which, combined with tree loss in the landscape, may compromise woodland sustainability.Andrew Mellon Foundation; Council for Scientific and Industrial Research (CSIR) Strategic Research Panel; Dept of Science and Technology (DST); Avatar Alliance Foundation; Margaret A. Cargill Foundation; David and Lucile Packard Foundation; Gordon and Betty Moore Foundation; Grantham Foundation for the Protection of the Environment; W. M. Keck Foundation; John D. and Catherine T. MacArthur Foundation; Exxaro Chairman's Fund; Applied Centre for Climate and Earth System Science; DST/NRF Centre of Excellence in Tree Health Biotechnology; NRF Innovation Scholarship [UID: 95030].http://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1600-05872018-11-30hj2017Geography, Geoinformatics and Meteorolog
What lies beneath : detecting sub-canopy changes in savanna woodlands using a three-dimensional classification method
QUESTION : Increasing population pressure, socio-economic development and
associated natural resource use in savannas are resulting in large-scale land
cover changes, which can be mapped using remote sensing. Is a three-dimensional
(3D) woody vegetation structural classification applied to LiDAR (Light
Detection and Ranging) data better than a 2D analysis to investigate change in
fine-scale woody vegetation structure over 2 yrs in a protected area (PA) and a
communal rangeland (CR)?
LOCATION : Bushbuckridge Municipality and Sabi Sand Wildtuin, NE South Africa.
METHODS : Airborne LiDAR data were collected over 3 300 ha in April 2008 and
2010. Individual tree canopies were identified using object-based image analysis
and classified into four height classes: 1â3, 3â6, 6â10 and >10 m. Four structural
metrics were calculated for 0.25-ha grid cells: canopy cover, number of canopy
layers present, cohesion and number of height classes present. The relationship
between top-of-canopy cover and sub-canopy cover was investigated using
regression. Gains, losses and persistence (GLP) of cover at each height class and
the four structural metrics were calculated. GLP of clusters of each structural
metric (calculated using LISA â Local Indicators of Spatial Association â statistics)
were used to assess the changes in clusters of eachmetric over time.
RESULTS : Top-of-canopy cover was not a good predictor of sub-canopy cover.
The number of canopy layers present and cohesion showed gains and losseswith
persistence in canopy cover over time, necessitating the use of a 3D classification
to detect fine-scale changes, especially in structurally heterogeneous savannas.
Trees >3 min height showed recruitment and gains up to 2.2 times higher in the
CR where they are likely to be protected for cultural reasons, but losses of up to
3.2-foldmore in the PA, possibly due to treefall caused by elephant and/or fire.
CONCLUSION : Land use has affected sub-canopy structure in the adjacent sites,
with the low intensity use CR showing higher structural diversity. A 3D classification
approach was successful in detecting fine-scale, short-term changes
between land uses, and can thus be used as amonitoring tool for savannawoody
vegetation structure.
Remove selectedThe Carnegie Airborne Observatory is made possible by the Avatar Alliance Foundation, Margaret A. Cargill Foundation, John D. and Catherine T. MacArthur Foundation,
Grantham Foundation for the Protection of the Environment, W.M. Keck Foundation, Gordon and Betty Moore Foundation, Mary Anne Nyburg Baker and G. Leonard
Baker Jr. and William R. Hearst III. Application of the CAO data in South Africa is made possible by the Andrew Mellon Foundation and the endowment of the Carnegie
Institution for Science.http://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1654-109X2016-07-31hb201
Unsustainable fuelwood extraction from South African savannas
Wood and charcoal supply the majority of sub-Saharan Africaâs rural energy needs. The
long-term supply of fuelwood is in jeopardy given high consumption rates. Using airborne
light detection and ranging (LiDAR), we mapped and investigated savanna aboveground
biomass across contrasting land uses, ranging from densely populated communal areas to
highly protected areas in the Lowveld savannas of South Africa. We combined the LiDAR
observations with socio-economic data, biomass production rates and fuelwood consumption
rates in a supplyâdemand model to predict future fuelwood availability. LiDAR-based biomass
maps revealed disturbance gradients around settlements up to 1.5 km, corresponding to the
maximum distance walked to collect fuelwood. At current levels of fuelwood consumption
(67% of households use fuelwood exclusively, with a 2% annual reduction), we calculate that
biomass in the study area will be exhausted within thirteen years. We also show that it will
require a 15% annual reduction in consumption for eight years to a level of 20% of households
using fuelwood before the reduction in biomass appears to stabilize to sustainable levels. The
severity of dwindling fuelwood reserves in African savannas underscores the importance of
providing affordable energy for rural economic development.The CSIR researchers were funded by the CSIR Strategic
Research Panel and the Department of Science and
Technologyâs Earth Observation Unit. SUCSES study (Sustainability in Communal Socio-Ecological Systems) which provided data on fuelwood use in
Justicia was funded by the South African National Research
Foundation.
The airborne campaign and analysis was funded by the
Andrew Mellon Foundation.http://iopscience.iop.org/1748-9326am201