Browsing by Author "Seetal, Ashwin R"

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    Apportioning human-induced and climate-induced land degradation: A Case of the Greater Sekhukhune District Municipality
    (2023-03) Kgaphola, Motsoko J; Ramoelo, Abel; Odindi, J; Mwenge Kahinda, Jean-Marc; Seetal, Ashwin R
    Land degradation (LD) is a global issue that affects sustainability and livelihoods of approximately 1.5 billion people, especially in arid/semi-arid regions. Hence, identifying and assessing LD and its driving forces (natural and anthropogenic) is important in order to design and adopt appropriate sustainable land management interventions. Therefore, using vegetation as a proxy for LD, this study aimed to distinguish anthropogenic from rainfall-driven LD in the Greater Sekhukhune District Municipality from 1990 to 2019. It is widely established that rainfall highly correlates with vegetation productivity. A linear regression was performed between the Normalized Difference Vegetation Index (NDVI) and rainfall. The human-induced LD was then distinguished from that of rainfall using the spatial residual trend (RESTREND) method and the Mann–Kendall (MK) trend. RESTREND results showed that 11.59% of the district was degraded due to human activities such as overgrazing and injudicious rangeland management. While about 41.41% was degraded due to seasonal rainfall variability and an increasing frequency of droughts. Climate variability affected vegetation cover and contributed to different forms of soil erosion and gully formation. These findings provide relevant spatial information on rainfall or human-induced LD, which is useful for policy formulation and the design of LD mitigation measures in semi-arid regions.
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    The Circular Economy as Development Opportunity: Exploring Circular Economy Opportunities across South Africa’s Economic Sectors
    (CSIR, 2021-12) Godfrey, Linda K; Nahman, Anton; Oelofse, Suzanna HH; Trotter, Douglas; Khan, Sumaya; Nontso, Zintle; Magweregwede, Fleckson; Sereme, Busisiwe V; Okole, Blessed N; Gordon, Gregory ER; Brown, Bernadette; Pillay, Boyse; Schoeman, Chanel; Fazluddin, Shahed; Ojijo, Vincent O; Cooper, Antony K; Kruger, Daniel M; Napier, Mark; Mokoena, Refiloe; Steenkamp, Anton J; Msimanga, Xolile P; North, Brian C; Seetal, Ashwin R; Mathye, Salamina M; Godfrey, Linda K
    The intention of this book is to present the CSIR’s position and interpretation of the circular economy, and to use it to drive discussions on where immediate circular economy opportunities are achievable in South Africa. Opportunities that can be harnessed by business, government and civil society. These circular economy opportunities are framed in this book within the context of the current challenges facing various economic sectors. The CSIR has selected seven, resource intensive sectors – mining, agriculture, manufacturing, human settlements, mobility, energy and water – for further assessment. Many of these economic sectors have seen significant declines over the past years, with agriculture, manufacturing, transport and construction all showing negative growth pre-COVID. These are all sectors under economic stress and in need of regeneration. South Africa stands on the threshold of profound choices regarding its future development path. Transitioning to a more circular economy provides the country with the opportunity to address many national priorities including manufacturing competitiveness, food security; sustainable, resilient and liveable cities; efficient transport and logistics systems; and energy and water security, while at the same time decarbonising the economy. The transition to a circular economy provides the country with an opportunity for green and inclusive development to be the cornerstone of a post-COVID economic recovery. The titles of this book chapters are the following: Chapter 1: Driving economic growth in South Africa through a low carbon, sustainable and inclusive circular economy. Chapter 2: Placing the South African mining sector in the context of a circular economy transition. Chapter 3: Supporting food security and economic development through circular agriculture. Chapter 4: Supporting the development of a globally competitive manufacturing sector through a more circular economy. Chapter 5: Creating resilient, inclusive, thriving human settlements through a more circular economy. Chapter 6: Facilitating sustainable economic development through circular mobility. Chapter 7: Decoupling South Africa’s development from energy demand through a more circular economy. Chapter 8: Decoupling South Africa’s development from water demand through a circular economy.
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    Distinguishing between human-induced land degradation from effects of rainfall: Case of The Greater Sekhukhune District Municipality
    (2022-11) Kgaphola, Motsoko J; Ramoelo, Abel; Odindi, John; Mwenge Kahinda, Jean-Marc; Seetal, Ashwin R
    Land degradation (LD) is a global issue that affects the sustainability and livelihoods of approximately 1.5 billion people, especially in arid/semi-arid regions. Assessing and identifying LD, especially driven by anthropogenic activities, is important for proposal of suitable sustainable land management interventions. Therefore, the study aimed to distinguish anthropogenic LD from rainfall effects in The Greater Sekhukhune District Municipality from 1990 to 2019. Vegetation production, thus Normalized Difference Vegetation Index (NDVI) from Advanced Very High-Resolution Radiometer (AVHRR) was used as an indicator for LD. Rainfall data from Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks (PERSIANN) has been widely proven to be highly correlated with vegetation productivity, hence was a climatic factor for assessment of vegetation dynamics. Linear regression was performed between NDVI and rainfall. Human-induced LD was then distinguished from that of rainfall using residual trend (RESTREND) method and Mann-Kendall trend test. Spatial RESTREND revealed that 11.59% of the district is degrading due to human impacts such as overgrazing and lack of rangeland management while 41.41% is due to rainfall impacts such as severe droughts in 1992, 2002-2004 and 2015. Additionally, climate variability affected vegetation and contributed to soil erosion and gully formations. Increase in vegetation biomass (53.83%) in other areas was noted to be result of bush encroachment (sign of LD) caused by human activities i.e., overgrazing and abandoned agricultural fields. These findings are crucial as they provide spatial information on rainfall or human-induced LD useful for policy formulation and designing LD mitigation measures in semi-arid regions.
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    Impact of land use and land cover change on land degradation in rural semi-arid South Africa: Case of the Greater Sekhukhune District Municipality
    (2023-05) Kgaphola, Motsoko J; Ramoelo, A; Odindi, J; Mwenge Kahinda, Jean-Marc; Seetal, Ashwin R; Musvoto, Constansia D
    In semi-arid regions, interactions between biophysical and socio-economic variables are complex. Such interactions and their respective variables significantly alter land use and land cover, degrade landscape’s structure, and impede the efficacy of the adopted land management interventions. This scenario is particularly prevalent in communal land tenure system or areas managed by a hybrid of traditional and state led institutions. Hence, this study sought to investigate the impacts of land use and land cover changes (LULCCs) on land degradation (LD) under communal rural districts, and the key drivers of habitat fragmentation in the Greater Sekhukhune District Municipality (GSDM), South Africa. The study used the wet and dry season multi-temporal remotely sensed image data, key-informant interviews, and workshop with tribal council to determine the major drivers of LULCC and LD. Results revealed that mines and quarries, subsistence and commercial cultivation, and thicket/dense bush LULCs declined significantly during the study period. These LULCs mostly declined in wet season, with loss in vegetation cover highly prevalent. Specifically, the highest conversions were from shrub/grassland to bare soil, thicket/dense bush to shrub/grassland, and shrub/grassland to residential, respectively. Generally, LULCC affected vegetation productivity within the study area, with increased negative NDVI values observed during the dry season. The findings from key informants and the tribal council workshop emphasized that soil erosion, abandonment of cropland, and injudicious land use (i.e. overgrazing and consequent bush encroachment) have severely degraded the land. The study also established that the degrading land can be attributed to the weakening local communal land management system, particularly the weakening tribal councils. The study recommends an urgent need for collaborative (i.e. government, tribal authorities, and land users) land management through designing relevant multi-stakeholder LD mitigation measures.
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    Impacts of Land Use Land Cover Change on Land Degradation: Case of the Greater Sekhukhune District
    (2021-10) Kgaphola, Motsoko J; Ramoelo, A; Odindi, J; Mwenge Kahinda, Jean-Marc; Seetal, Ashwin R
    Interaction between biophysical variables and socioeconomic conditions are far more complex and affect land cover and quality. These are aggravated by global climate change and climate variability in semi-arid regions. Therefore, the study investigates impacts of land use and land cover changes (LULCC) on land degradation (LD) and further investigates the rates and predictors of habitat conversion in the semi-arid Sekhukhune district, South Africa. The study uses remote sensing by providing long-term spatio-temporal information to assess LULC and LD between 1990 to 2019 over a five-year interval. LULCC impacts on LD is analysed using change detection i.e., NDVI change, LULC conversion and key informant interviews (natural resource managers, crop and animal production, extension officers).
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    Social-ecological system understanding of land degradation in response to land use and cover changes in the Greater Sekhukhune District Municipality
    (2023-02) Kgaphola, Motsoko J; Ramoelo, Abel; John Odindi, J; Mwenge Kahinda, Jean-Marc; Seetal, Ashwin R; Musvoto, Constansia D
    Land degradation is a major risk to the sustainability and functioning of socioecological systems (SES), especially in arid/semiarid regions. By understanding a system and its interlinkages, the socioecological approach offers an innovative way to explore degradation. This is achieved through a synergistic analytical approach to improve the ability of identifying and understanding systems, predicting their behaviour, and modifying them to achieve the desired effects. This research provides a roadmap for an integrated interdisciplinary approach that is a critical factor in understanding the drivers of land degradation. It can be used to determine appropriate land management action. The aim of this study was, therefore, to apply an integrated SES approach to a degraded rural semiarid context to address the land degradation problem using the Greater Sekhukhune District Municipality in South Africa as a case study. The Drive Pressure State Condition and four Responses (DPSCR4) framework (modified from Drive Pressure State Impact and Response (DPSIR)) was used as the SES to assess land degradation. Key informant interviews, focus group discussions with local pastoralists and traditional authorities, and the scientific literature were triangulated to systemically analyse DPSCR4. Land degradation neutrality (LDN) was integrated into the framework to draw conclusions on sustainable land management (SLM). The results show that the main anthropogenic activities driving land degradation are overgrazing, land tenure, poverty and disenfranchisement, unsustainable land use, and cropland abandonment, which favour bush encroachment. Natural factors such as topography, dispersive duplex soils, and climate variability and change predispose the district to soil erosion and gully formation. In combination with human activities, this exacerbates land degradation. The study recommends measures to enable informed integrated land use planning and management using the DPSCR4 and LDN frameworks to improve landscape conditions in rural semiarid regions and provide sustainable livelihoods for the rural poor in developing countries who depend on natural resources.
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    Validation and verification of lawful water use in South Africa: An overview of the process in the KwaZulu-Natal Province
    (IEEE, 2016-10) Kapangaziwiri, Evison; Mwenge Kahinda, Jean-Marc; Dzikiti, Sebinasi; Ramoelo, Abel; Cho, Moses A; Mathieu, Renaud SA; Naidoo, Mogesh; Seetal, Ashwin R; Pienaar, Harrison H
    South Africa is a water-stressed country which has, over the years, strived to adopt a rational, just and equitable way to manage this limited resource. The National Water Act (Act No.36 of 1998) (NWA) provides the legal framework to achieve this objective. Since 2003, the government embarked on a national process to: validate (confirm the quantum of), and; verify (establish the lawfulness of) water uses that exceed domestic requirements. The objective of the project was to determine how much water is allocated for: (1) existing lawful use in accordance with specific requirements of the NWA, and; (2) current water uses. The project identified users with or without registered use entitlements, whether claims for registered uses were correct, underestimated , overestimated or false; and confirmed the lawfulness of each water use in accordance with water legislation that pre-dated the NWA. The process included identifying land and non-land based water uses (industrial, mining and bulk potable water supplies, irrigation, crop types and impoundments) using remote sensing (RS) techniques for both a qualifying (defined as two years before the enactment of the NWA) and the current periods. Crop irrigation requirements were estimated using the South African Procedure for estimating irrigation WATer requirements (SAPWAT), while the Gush curves were used to quantify Stream Flow Reduction Activities (SFRAs) due to commercially afforested areas. The boundaries of farm reservoirs were delineated from RS and the volumes calculated using a regression approach. Estimates of the irrigation water requirements, SFRAs and reservoir volumes formed the basis for interaction between the Department of Water and Sanitation and water users to confirm their uses; and subsequently, to update the Water Authorisation and Registration Management System (WARMS), a database of water users. While WARMS indicated a total of approximately 16 000 registered users in the KwaZulu-Natal province, up to 6000 additional water users, mostly currently unregistered, are expected to be registered in the updated database. Despite certain project methodology challenges and limitations, the project forms a critical basis for all other aspects of water management, informs macro- and micro-water resource planning, water allocation reform, as well as water use compliance, monitoring and enforcement.