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Soil erosion is a global environmental problem and a pervasive form of land degradation that threatens land productivity and food and water security. Some of the biggest sources of sediment in catchments are cultivated and abandoned lands. However, the abandonment of cultivated fields is not well-researched. Our study assesses the level of degradation in cultivated and abandoned lands using a case study in South Africa. We answer three main questions: (1) What is the extent of crop field degradation on used, partly used, and abandoned fields? (2) What are the drivers of field abandonment in relation to land degradation? (3) Can proposed sustainable land management interventions tackle the dynamics of land abandonment and associated degradation? To answer these questions, cultivated and abandoned lands were mapped in a pilot catchment with ArcGIS tools and assigned severity codes and classified according to status, degradation, and encroachment. Systems diagrams were developed to show the interactions between agricultural land use and the level of degradation and leverage points in the system, with interventions assessed via a multi-criteria analysis. The results revealed that 37% of the total mapped area of croplands in the pilot site was abandoned and 20% of those lands were highly degraded. We argue that the innovative application of systems thinking through causal loop diagrams (CLDs) and leverage point analysis, combined with spatial and multi-criteria analyses, can assist with planning SLM interventions in similar contexts in the developing world. [ABSTRACT FROM AUTHOR]

The need to effectively govern and manage communal rangeland resources has become more important over the past two decades, given the extent of biodiversity loss caused by a myriad of drivers interacting at different scales.Using in‐depth interviews, participant observations and historical information from organisational records, we analysed the application of governance objectives between 1947 and 2017 and their corresponding rangeland condition outcome in Machubeni (South Africa) communal lands.The results show that while the application of governance objectives varied through time, there has been a steady degradation of local rangeland resources since apartheid, due to internal and external drivers of change. This reveals a disconnection between management and resource conditions, suggesting that a return to effective governance alone will not necessarily result in improved rangeland condition in Machubeni, but that more radical steps such as prolonged periods of resting, reseeding and building individual and group agency, are needed. These findings can help practitioners working in post‐colonial territories to design effective rangeland management models. Read the free Plain Language Summary for this article on the Journal blog. Read the free Plain Language Summary can be found within the Supporting Information of this article. [ABSTRACT FROM AUTHOR]

Understanding people's practices, knowledge and perceptions of the use of fire and fire regimes can inform fire management plans that could contribute to savanna conservation and sustainable management. We investigated the frequency of fire use, control and perceptions of fire regimes for selected livelihood and socio-cultural activities in six districts in the Guinea savanna of Ghana. The six districts were selected to have a good representation of fire prone areas in the region based on fire frequency data obtained from the CSIR Meraka Institute, South Africa. A multiple regression analysis showed that people's use of fire for the selected socio-cultural activities from district, occupation, gender, age and ethnic group significantly predicted fire use for the activities R2 = 0.043, F (5,498) = 5.43, p < 0.000. Age and occupation added significantly to the use of fire. The study revealed that the majority of respondents (83%) across the study districts used fire once a year for at least one of the following activities: land preparation, weed/pest control, burning postharvest stubble, bush clearing around homesteads, firebreaks, charcoal burning and hunting. The study also showed a higher frequency of fire use for land preparation for cropping than for the other activities. Less than a fifth of the respondents (17%) indicated that they do not use fire for any of the selected activities. The majority of respondents (65%) mentioned that they controlled their use of fire to prevent destruction to property or injuring humans. The study revealed a higher frequency of fire use in the dry season for land preparation for cropping. However, respondents rated season of burning as the most important attribute, with little attention to the other attributes of a fire regime, contrary to what is theoretically recognized. Understanding traditional fire use practices in terms of how to regulate the mix of frequency, intensity/severity, season, size and type of fire for these and other socio-cultural purposes could help to mitigate and/or manage bushfires in West African savannas and enhance savanna conservation and management. Hence, the need to better understand people's knowledge and perceptions of fire regimes in fire assisted socio-cultural practices in West Africa. [ABSTRACT FROM AUTHOR]

Summary: Throughout southern Africa, there have been growing concerns about the rates of ecosystem degradation. This issue and natural resource governance concerns in general remain key challenges. We conducted a scoping review of 135 articles to inductively assess how governance challenges have manifested in natural resource management during 2010–2020 in southern Africa. The paper's findings show that governance challenges in southern Africa are 'hydra-headed'. The results suggest that governance challenges related to the maintenance of system integrity and functioning – specifically lack of coordination, accountability, capacity, skills and resources to define effective natural resource management – were the most reported in literature. Challenges related to achieving socially equitable governance were the second most mentioned, followed by those related to institutional robustness. Challenges related to the adaptability and flexibility of institutions, specifically learning, monitoring capacity and innovation, were the least identified, showing that these areas are poorly studied or that these attributes are considered less problematic for achieving sustainable outcomes. Furthermore, the review highlights critical gaps – the limited engagement with governance-related frameworks, specifically polycentricity, adaptive governance and social-ecological stewardship. In concluding, we highlight governance reforms and future research needs on the topic of natural resources in southern Africa. [ABSTRACT FROM AUTHOR]

Relationships between protected area managers and adjacent communities, as well as communities' attitudes, views and perceptions of these areas, are critical for the success of conservation efforts. It is important for protected area managers and administrators to understand how local communities view these areas and their management, so that they can build sustainable working rel ationships. This paper is based on a survey of 375 semi-structured questionnaires administered to household heads, living at distances ranging from the edge of the reserves to 50 km away from the reserve boundary across the Great Fish River, Mkambati, Hluleka, and Tsolwana nature reserves in the Eastern Cape Province, South Africa. The paper provides a longitudinal assessment of households' knowledge about the role of reserves and the reserves' impacts on livelihood assets. In addition to households' knowledge about the role of reserves, the paper also provides an assessment of people's attitudes towards their location and management, as well as views on the best way to manage the reserves. For 79% of community members, reserves were important as they were seen to conserve biodiversity and valuable ecological systems necessary for sustaining life. Most (75%) respondents indicated that closely located reserves gave them opportunities to learn about nature conservation and to subsidize their incomes through tourism ventures. However, 58% had a problem with reserves' staff, due to restrictions on resource use, which negatively impacted their livelihoods. Over half (51%) of the households argued that sustainable conservation can only be achieved through an integrated approach where conservation and local communities' needs are given equal weight. We concluded that reserve managers should look at communities as active partners in the management of protected areas if sustainable conservation objectives are to be realised. [ABSTRACT FROM AUTHOR]

Biodiversity is the foundation of life-support systems on earth and underpins the delivery of ecosystem services (ES) important for human well-being. The loss of biodiversity worldwide, however, remains one of the most daunting challenges. Among the major causes of biodiversity loss is habitat loss due to transformation of land to agricultural, mining and urban areas. We applied the Integrated Valuation of Ecosystem Services and Trade-offs (InVEST) biodiversity modelling tool to assess the condition of habitats to support the delivery of ES in a biosphere reserve (BR) in South Africa. Results indicated that 72% of the surveyed habitats were of high quality to provide the necessary services. However, some of the habitats were found to be affected by threats as follows: low (0–20%) to moderate (20–32%) habitat loss was recorded in habitats adjacent to mining and plantation areas, and high (32–56%) to severe (56–95%) habitat loss was recorded in habitats in close proximity to urban and cultivated areas. At least 56% of the vegetation types found in the study area were threatened by transformation to agriculture, mining and urban areas. We strongly recommend that existing biodiversity policies and legislation should be enforced to avoid habitat loss and degradation. [ABSTRACT FROM AUTHOR]

Aim We examined differences in the architecture of African and Australian savanna trees. We sought to attribute variation in tree architecture to current environments, wood density and phylogeny, and thereby elucidate the relative importance of biogeographic idiosyncrasies versus current factors in underpinning architectural differences. Location Africa and Australia. Methods We compiled canopy diameters and stem diameters from 4867 trees of 97 species and heights and stem diameters from 10,786 trees of 155 species from a range of African and Australian savanna ecosystems and climates. Using Bayesian methods we first estimated continental-scale savanna tree allometries, ignoring species differences. We then examined continental differences in species-specific allometries accounting for trait covariation using a phylogeny of our study species. Environmental variables and wood density data were included as covariates, allowing us to assess the potential underpinning of regional differences in tree allometries by differences in current environments and traits. Results Substantial allometric differences exist between Australian and African savanna trees. Australian trees are on average 6 m taller at 20 cm diameter, with a 53% smaller canopy area than African trees. However, this extreme continental-scale variation is driven by the architecture of only a few taxa in this study - Vachellia and Senegalia versus Eucalyptus and Corymbia - rather than systematic differences between species, wood density and environment. These same genera often dominate the woody strata of South African and Australian savannas, respectively. Main conclusions Stark differences in the architecture of African and Australian savanna tree taxa are not a product of environmental differences and are not consistent across species. Rather, the most likely explanation is the different evolutionary histories of African and Australian savannas, which share no woody species. We consider that these architectural differences are likely to impact regional patterns of woody biomass accumulation. [ABSTRACT FROM AUTHOR]

Using an analysis of aerial photographs from 1942, 1985 and 2004 we assessed the impact of changing land tenure and land-use regimes on the cover of thicket vegetation on the Grahamstown commonage. Land-use impacts were examined by comparing plant species composition within three vegetation types between sites incorporated into commonage for different lengths of time and sites outside the commonage. Results showed that thicket cover increased by 87% between 1942 and 1985 but declined by 11% between 1985 and 2004. The increase in thicket cover was highest on land where goat browsing and wood harvesting was excluded. There was a decline in thicket cover when uncontrolled goat browsing and wood harvesting were introduced. An analysis of plant species composition suggests an increase in the impact of livestock in areas closest to the urban area and with time since inclusion into commonage. Such areas exhibited greater cover of Increaser II grasses and dwarf shrubs in the herbaceous layer and lower cover of succulents within subtropical thicket. We interpret the decline in thicket cover and shift to a less palatable and less productive vegetation as resulting from the open-access land use system that has prevailed on the commonage since 1994. [ABSTRACT FROM AUTHOR]

We examined the effect of changes in land use and land tenure on bush encroachment and vegetation condition. An analysis of aerial photographs from three time steps (1949, 1985 and 2004) was used to document changes in woody plant density in different vegetation types on commonage and an adjacent commercial farm in Fort Beaufort, South Africa. Rangeland condition was assessed in different vegetation units of the area and woody plant density was related to distance from urban settlement. Results showed that there has been an increase in woody plant cover in both commonage and commercial farming areas, particularly between 1949 and 1985. However, since 1985, increased rates of urbanisation have stabilised, and in some areas reduced, woody plant thickening, especially at locations closest to urban settlements. Bush encroachment is being controlled to some extent by fuelwood harvesting and goat browsing, resulting in a reduction in height of favoured woody species such asAcacia karroo(Vachellia karroo). There has been a shift to less palatable browse species on the commonage areas and the condition of the grass sward is poor. Change in woody plant cover is significantly influenced by changing patterns of land use and land tenure over time which, in turn, affect rangeland condition. [ABSTRACT FROM AUTHOR]

Environmental systems are in constant flux, with feedbacks and non-linearities catalysed by natural trends and shocks as well as human actions. This poses challenges for sustainable management to promote human well-being. It requires environmental understanding and application that can accommodate such fluxes and pressures, as well as knowledge production systems and institutions that produce graduates with appropriate skills. In this article we consider these challenges in the South African context. Firstly, we summarise six significant environmental realisations from the last decade of environmental science internationally and question what they mean for the teaching of environmental science and research into environmental systems in South Africa in the near future. We then consider these lessons within the context of a horizon scan of near-term pressing environmental issues in South Africa. These include water-use efficiency, poverty, food security, inequities in land and resource access, urbanisation, agrochemicals and water quality, promoting human well-being and economic adaptability in the face of climate change, and imbuing stronger environmental elements and stewardship into the integrated development planning processes and outcomes. Lastly, we consider the knowledge areas and skills that environmental graduates will require to be able to confront these problems in South Africa and simultaneously contribute to international debates and understandings around the complexity of environmental systems and how to manage them. [ABSTRACT FROM AUTHOR]

The negative impacts of invasive alien species on the environment are well documented. However, despite the predominantly negative perceptions associated with invasive species, it is evident that a number of these plants have been part of the landscape for generations and have numerous commercial and non-market uses. Consequently, there is a need for research that considers the impact of invasive species on the livelihoods and well-being of local communities. The authors investigated the contribution that the trade in prickly pear (Opuntia ficus-indica), an invasive alien species, makes to the household income streams of poor trading households. The research highlights the apparent conflict of interests and trade-offs that exists between local traders, for whom the sale of the prickly pear provides a livelihood source, and the South African Government, who are actively seeking to remove the plant from the landscape. [ABSTRACT FROM AUTHOR]

Copyright of African Journal of Ecology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of African Journal of Ecology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Human-induced fires are a major disturbance in Baikiaea plurijuga woodland savannas that are economically important for timber production. Most fires occur during the late dry season, when they may severely damage woody plants. Prescribed burning during the early dry season is a management strategy to reduce fuel loads and thus the incidence of intense fires during the late dry season. There is, however, little information on fire behaviour characteristics of early dry season fires. We studied the relationship between experimental fuel conditions and fire behaviour by lighting 15 fires during the early dry season in a Baikiaea woodland. Fire intensity ranged from 25 to 1341 kW m-1, while rate of spread of fire varied between 0.01 and 0.35 m s-1. Fire intensity and rate of spread were positively related to flame height, leaf-scorch height and proportion of the area burnt. The relationships suggest that fire characteristics can be retrospectively determined using a variable such as scorch height. The grass fuel load, wind speed, relative humidity and to a lesser extent fuel moisture were important predictors of rate of spread, flame height, leaf-scorch height and proportion of the area burnt, with no impact due to the lifter fuel load. The grass fuel load and wind speed had a positive effect on rate of spread, whereas relative humidity and fuel moisture had a negative effect. These findings indicate that managers can predict the likely damage to woody plants during an early dry season burn by assessing the grass fuel load and weather conditions at the time of burning. [ABSTRACT FROM AUTHOR]

Feeding a growing global population using conventional agricultural practices is leading to adverse environmental impacts. There is a call for alternative forms of agriculture that address social, economic, and environmental aspects of sustainability. Permaculture is a holistic design framework that incorporates sustainable agricultural practices, potentially improving livelihoods. This study looked at the challenges and benefits of permaculture in improving rural livelihoods in Zimbabwe and South Africa. We used semi-structured interviews to collect data. Permaculture contributed over 40% to total income for participants in both countries. However, permaculture was not the dominant source of income and periodically straddled multiple livelihood strategies. The main benefits of permaculture were identified as improved human health, increased resilience to environmental changes, and reduction of input costs. The key challenges included high labour input, infestation of pests and diseases, and lack of knowledge on permaculture practices. Although permaculture presents significant challenges, its integration with other forms of sustainable agricultural practices can contribute to improved rural livelihoods. [ABSTRACT FROM AUTHOR]

Deagraianisation is a worldwide phenomenon with widespread social, ecological and economic effects yet with little consensus on the local or higher level causes. There have been contested views on the causes and consequences of deagrarianisation on South Africa’s Wild Coast, which is an international biodiversity hotspot. Using GIS, household interviews and ecological sampling, we compared the perspectives of current and former cultivators as to why some have abandoned farming, whilst also tracking the uses and woody plant cover and composition of fields abandoned at different periods. The GIS analysis showed that field abandonment had been ongoing over several decades, with a decline from 12.5 % field cover in 1961 to 2.7 % in 2009. The area of forests and woodlands almost doubled in the corresponding period. There was a distinct peak in field abandonment during the time of political transition at the national level in the early 1990s. This political change led to a decrease in government support for livestock farming, which in turn resulted in reduced animal draught power at the household and community level, and hence reduced cropping. The study showed it is largely the wealthier households that have remained in arable agriculture and that the poorer households have abandoned farming. The abandoned fields show a distinct trend of increasing woody biomass and species richness with length of time since abandonment, with approximately three woody plant species added per decade. Most local respondents dislike the increases in forest and woodland extent and density because of anxiety about wild animals causing harm to crops and even humans, and the loss of an agricultural identity to livelihoods and the landscape. [ABSTRACT FROM AUTHOR]