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South Africa is highly susceptible to climate variability and long-term climatic shifts, necessitating a comprehensive understanding of changing extreme precipitation patterns to guide effective mitigation and adaptation responses. This study examined variations in extreme precipitation indices from 1981 to 2023 across the eastern Free State Province using daily rainfall records derived from the Climate Hazards Group InfraRed Precipitation with Station data (CHIRPS). Ten extreme precipitation indices were evaluated, with trend detection conducted through the Innovative Trend Analysis (ITA) technique. Findings indicate that the majority of municipalities exhibited statistically significant declining trends (p < 0.05) in total wet-day precipitation (PRCPTOT), R99P, R95P, the Simple Daily Intensity Index (SDII), CDD, RX5day, R20mm, and R10mm, suggesting an overall reduction in both heavy and moderate rainfall occurrences. In contrast, significant upward trends (p < 0.05) were identified in CWD, and RX1day, reflecting a shift toward prolonged wet periods and more intense short-duration rainfall events. Taken together, these divergent patterns point to the simultaneous emergence of heightened drought vulnerability driven by reduced cumulative rainfall and increased flood risk linked to intensified precipitation extremes. These results underscore the importance of forward-looking, climate-resilient water resource management and context-specific adaptation strategies suited to the eastern Free State’s complex mountainous terrain.

Climate variability poses a significant threat to smallholder farmers in the Gwayi catchment, Zimbabwe. This study investigated the spatiotemporal dynamics of agrometeorological droughts from 1990 to 2020 using the Standardized Precipitation Index (SPI), Standardized Precipitation Evapotranspiration Index (SPEI), Vegetation Condition Index (VCI), and Vegetation Health Index (VHI). The triangulation of these indices provided a comprehensive understanding of drought dynamics. Severe to extreme drought events were identified in 1995, 1998, 2005, 2016, 2018, and 2020, while moderate droughts were consistently detected across all indices. Favourable conditions were observed in 2000 and 2006. A strong positive correlation (r = 0.88) between VHI and VCI suggests their similar effectiveness in reflecting vegetation health. In contrast, moderate correlations between VHI and SPI (r = 0.30), VHI and SPEI (r = 0.39), VCI and SPI (r = 0.28), and VCI and SPEI (r = 0.40) indicate that these indices capture complementary information, reflecting not only precipitation deficits but also the impacts of temperature, soil moisture, and land cover changes. The SPI and SPEI displayed a strong positive correlation (r = 0.78), aligning in their sensitivity to precipitation and evapotranspiration. Spatial analysis revealed a pronounced north-south drought gradient, with the southwestern region being particularly vulnerable, underscoring the need for targeted interventions.

Profiling eco-environmentally vulnerable (EV) areas can contribute to the development of mechanisms for environmental protection and sustainable management of ecological resources. Land cover change, population density, annual precipitation, mean temperature, remotely sensed indices, actual evapotranspiration, land surface temperature (LST), and runoff for the catchment for 1990, 2000, 2011, and 2020 were used to assess spatiotemporal ecological vulnerability. Spatial principal component analysis (SPCA) was used to assess thematic vulnerability for each year. The analytical hierarchical process (AHP) was then used to determine the weighting of the thematic maps to produce the final ecological vulnerability maps. Our results showed that most of the sub-basin had low and moderate vulnerability in 1990, 2000, 2011, and 2020, with the combined proportion of these areas being 80.6%, 55.45%, 83.92%, and 85.1%, respectively. The areas classified as high vulnerability decreased steadily over the investigated years, except in 2000, where an increase was observed. Most areas in the southern parts of the sub-basin were classified as moderately vulnerable, while high vulnerability values were recorded in the northern areas. The southern parts of the Upper Mzingwane basin are drier and less populated than the northern parts. The spatial architecture of vulnerability presented will help inform decision makers in mitigation planning and overall disaster risk management initiatives in the basin.

The marula tree can play a vital role to enhance the livelihoods within marginalised communities and aid forest management efforts. This research aimed to explore the utilisation and management of the marula tree (Sclerocarya birrea) in ward 3 of Beitbridge district, Southern Zimbabwe. A representative sample of 300 randomly selected households from five villages of ward 3 were interviewed telephonically and through the WhatsApp social media platform using a semi-structured questionnaire. The study observed that 95% of the sampled households harvested and utilised marula fruits to produce several products including jam, marula wine, nuts for consumption, and soda. In addition, marula makes a significant contribution to family income at (35%) when in season compared to other livelihood options such as livestock rearing and cropping. An average of 443 kg of marula fruits were harvested per season per village and there were significant differences (p < 0.05) in quantities harvested across villages. Households involved in marula fruit trading increased by 27% in 20 years due t\\o an improvement in the marula tree value chain in the district. Therefore, there is a distinct possibility for overutilisation of the marula tree products, which necessitates the need for the development of effective marula forest management plans.

Climate variability and land-use changes are critical challenges impacting agriculture globally, with Zimbabwe’s Gwayi catchment area experiencing noticeable effects. This study investigated how smallholder farmers in the region perceive these changes and their influence on agricultural productivity and livelihoods. The research addresses the gap in understanding local farmer experiences with climate change and land-use modifications in the context of food security. A cross-sectional survey (n = 483) was conducted using self-administered questionnaires to capture demographic information, perceptions of climate variability, land-use changes, and their impacts on agriculture. The results indicate a trend of increasing droughts, dry spells, and heatwaves, alongside altered rainfall patterns and rising temperatures, corroborating the observed climate data. Environmental degradation, including deforestation, gully formation, and land expansion, exacerbates these changes. Consequently, farmers reported substantial reductions in crop yields, with 84.05% experiencing significant-to-very negative impacts, alongside declining livestock health (32.51% reporting very negative impacts), increased water scarcity (43.3% reporting drying water sources), and more frequent disease outbreaks. These challenges collectively contributed to heightened food insecurity, with 74.12% of households reporting negative impacts on their food supply. The study underscores the synergistic impacts of climate variability and land-use changes, highlighting the urgent need for climate-smart agricultural practices and sustainable land management to enhance resilience and ensure long-term food security for smallholder farmers in the Gwayi catchment.

This paper investigates the impacts of policy and governance institutions on rangeland management practices in southern Africa. A scoping review was conducted, using literature from Web of Science, JSTOR, Scopus and Africa-wide bibliographic databases in the past three decades. The results revealed that several initiatives have been implemented in southern Africa to improve the condition of rangelands, including livestock destocking policies, grazing schemes, improved forage grasses, veld legume reinforcement, high-market beef value chains and agroforestry technology. However, the success of these initiatives has been limited due to a lack of meaningful participation in rangeland management. Moreover, the absence of responsive policies to support communal rangeland management in southern Africa has led to their transformation into unsustainable systems. Additionally, commercial interests often drive national-level policies and tend to disempower traditional institutions, causing conflicts and discord in rangeland management. Therefore, unrolling participatory bottom-up approaches will be essential for inclusive and sustainable rangeland management.

Despite extensive research on climate change impacts and adaptation strategies in Zimbabwe, their effectiveness from the perspective of smallholder farmers, particularly in the Gwayi catchment remains insufficiently understood. This study evaluated adaptation strategies in response to land use change and climate variability using a mixed-methods approach. Data were collected through a survey of 483 smallholder farmers, 10 focus group discussions (8–12 participants), and interviews with 25 key informants. Results show that despite farmers' awareness of improved practices, adaptation remains constrained by limited access to water, quality seeds, and technology (64%), financial constraints (46%), and knowledge gaps (19%). The most common adaptation strategies include soil water conservation (85%), drought-resistant crops (80%), early planting (55%), and diversification (49%), with soil water conservation and drought-tolerant crops being the most widely practiced and perceived as most effective. Regression analysis indicates that livestock ownership, participation in community climate-resilient programs, and recent drought experiences significantly (p < 0.05) influence both the choice and number of adaptation strategies adopted. These findings highlight the need for context-specific interventions to mitigate the impacts of climate and land use changes on food security. Strengthening resilience among smallholder farmers requires improved resource access, livestock support, community-based resilience programs, capacity building, financial aid, and enhanced drought preparedness. Implementing these measures will bolster adaptive capacity and promote sustainable agricultural practices in the face of climate uncertainty.

Ecosystem services in the South African grassland biome are being impacted by the presence of invasive alien plants (IAPs), particularly from the Australian genus Acacia. IAPs have elevated landscape water use and determining water fluxes is crucial to defining suitable interventions. This study evaluates three models of water flux over IAP-invaded grassland against evapotranspiration (ET) measured by a large-aperture scintillometer (LAS). ET was modelled using an energy balance model (MEDRUSH), a biophysical model (Penman-Monteith-Leuning (PML)) and a remotely sensed product (MOD16), and their results compared with ET measured by the LAS. ETLAS was measured during an abbreviated field campaign in November 2019 over a dense silver wattle (A. dealbata) stand associated with hillslope seeps. Of the three models tested against the LAS campaign, MEDRUSH performed well-enough to be used to model ET over the continuous scientific-grade micro-meteorological record (315 days). We used MEDRUSH to model ET over the invaded hillslope seeps and compared this with the expected ET that would occur over the adjacent, un-invaded grassland. Total ET over the IAP-invaded area was approximately 536 mm (60% of reference ET) as compared with the grassland (202 mm), showing that woody encroachment significantly increases landscape water use. To estimate the local impact of this, we used earth observation to determine the area of woody invasion in a 2 664 km2 regional window. Approximately 10% (274 km2) of this window was invaded by IAPs and, assuming the geographic window was representative of all the areas invaded by wattle, this represents ~ 89 000 ML of water used annually by the IAPs. Removal of wattle, followed by suitable restoration of landscape functionality, would greatly enhance rangeland productivity and water production from hillslope seeps.

The six major mountain ranges in South Africa support critically important ecosystem services—notably water production—and are rich in biodiversity and endemism. These mountains are threatened by detrimental land uses, unsustainable use of natural resources, climate change, and invasive alien plants. Invasive alien plants pose substantial and rapidly increasing problems in mountainous areas worldwide. However, little is known about the extent of plant invasions in the mountains of South Africa. This study assessed the status of alien plants in South African mountains by determining sampling efforts, species compositions and abundances across the six ranges in lower-and higher-elevation areas. Species occurrence records were obtained from three databases that used various approaches (roadside surveys, citizen science observations, focused botanical surveys). Most mountain ranges were found to be undersampled, and species composition assessments were only possible for two ranges. The majority of abundant alien plants in both the lower- and higher-elevation areas were species with broad ecological tolerances and characterised by long distance seed dispersal. These prevalent species were mostly woody plants—particularly tree species in the genera Acacia, Pinus, and Prosopis—that are contributing to the trend of woody plant encroachment across South African mountains. We suggest improved mountain-specific surveys to create a database which could be used to develop management strategies appropriate for each mountain range.

Accurately measuring evapotranspiration (ET) is important in the context of global atmospheric changes and for use with climate models. Direct ET measurement is costly to apply widely and local calibration and validation of ET models developed elsewhere improves confidence in ET derived from such models. This study sought to compare the performance of the Penman-Monteith-Leuning (PML) and Penman-Monteith-Palmer (PMP) ET models, over mesic grasslands in two study sites in South Africa. The study used routine meteorological data from a scientific-grade automatic weather station (AWS) to apply the PML and PMP models. The PML model was calibrated at one site and validated in both sites. On the other hand, the PMP model does not require calibration and hence it was validated in both sites. The models were validated using ET derived from a large aperture scintillometer (LAS). The PML model performed well at both sites with root mean square error (RMSE) within 20% of the mean daily observed ET (R2 of 0.83 to 0.91). Routine meteorological data were able to reproduce fluxes calculated using micrometeorological techniques and this increased the confidence in the use of data from sparsely distributed AWSs to derive reasonable ET values. The PML model was better able to simulate observed ET compared to the PMP model, since the former models both transpiration and soil evaporation (ES), while the latter only models transpiration. Hence, the PMP model systematically underestimated ET in a context where the leaf area index (LAI) was < 2.5. Model predictions in the grasslands could be improved by incorporating the ES component in the PMP model while the PML model could be improved by careful choice of the number of days to be used in the determination of the fraction of ES.