How important is green infrastructure in small and medium-sized towns? Lessons from South Africa
- Authors: Shackleton, Charlie M , Blair, Andrew , De Lacy, Peter , Kaoma, Humphrey , Mugwagwa, Noster , Dalu, Mwazvita , Walton, Wesley
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/398321 , vital:69400 , xlink:href="https://doi.org/10.1016/j.landurbplan.2016.12.007"
- Description: The current nature and challenges of urbanisation in sub-Saharan Africa display several unique features only weakly evident on other continents. Key ones include the current high rates of population growth, inadequate planning and governance systems, concentration in small and medium-sized towns, and increasing urban poverty. These shape the extent, nature and use of ecosystem services provided by urban green infrastructure. This paper first examines the location of green infrastructure across nine towns, showing that it is unequal between suburbs and that the bulk is located under private tenure (74%) rather than in public spaces. We then consider the extent and patterns of use of selected provisioning and cultural ecosystem services from green infrastructure in different locations within towns, including private gardens, public parks and street trees. The results show significant use of green infrastructure for a range of provisioning and cultural services as well as its contribution to spiritual and mental wellbeing. Provisioning contributions are both in regular support of livelihood needs as well as increased use after a covariate shock (a flood), both of which help reduce household vulnerability. Lastly, our results show the expressed level of support and willingness-to-pay or work amongst urban residents for green infrastructure and the services it provides. Whilst the composite results indicate marked variation between and within towns, they show that there is widespread use of green infrastructure for both basic needs as well as for more aesthetic and psycho-spiritual appreciation and recreation, in small and medium-sized towns in a developing country such as South Africa.
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How to establish and run a catchment management forum
- Authors: Palmer, Carolyn G , Holleman, Helen , Wolff, Margaret G
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , report
- Identifier: http://hdl.handle.net/10962/437894 , vital:73420 , ISBN 978-1 4312-0986-6 , https://wrcwebsite.azurewebsites.net/wp-content/uploads/mdocs/SP 118-18 web.pdf
- Description: The user-friendly series of “How to….” handbooks are aimed at staff and stakehold-ers in catchment management forums (CMFs), catchment management agencies (CMAs) and municipalities. The handbooks are not all written at exactly the same level of “user-friendliness”, it depends on the topic, and target users.
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How to think about water for people and people for water: Some for all, forever
- Authors: Palmer, Carolyn G
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , report
- Identifier: http://hdl.handle.net/10962/437922 , vital:73422 , ISBN 978-1 4312-0985-9 , https://wrcwebsite.azurewebsites.net/wp-content/uploads/mdocs/SP%20117-18%20web.pdf
- Description: Water for people and people for water. We need water and water needs us. That is what this book is about. Water is the basis of all life. No plant, animal or person on earth can survive without it. In fact, all organisms are mostly made up of water. Wa-ter shapes the earth’s surface. It is a fundamental part of climate processes. Out in the natural world, water is not found in taps, buckets and glasses but in rivers, wet-lands, lakes, dams, estuaries, groundwater and the sea. It falls from the sky as rain, runs off the landscape, filters into the soil, flows to the sea in rivers, is stored in dams, evaporates into the sky, and rains back onto the earth. This is the water cycle. People need water for all sorts of things, for drinking, washing, cooking, growing food, in industries, and to dilute and transport wastes. But in the process of using water, people can damage rivers, wetlands, lakes and other watery places. Dam-aged ecosystems do not work very well and may fail us when we need them most. The message of this book is – look after water in the places where it is naturally found – look after water and water ecosystems because you need them so much.
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How to understand environmental water quality in water resources management
- Authors: Palmer, Carolyn G
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , report
- Identifier: http://hdl.handle.net/10962/437951 , vital:73424 , ISBN 978-1 4312-0992-7 , https://wrcwebsite.azurewebsites.net/wp-content/uploads/mdocs/SP%20124-18%20web.pdf
- Description: We all depend on water for life, well-being and economic prosperity. In our homes water is used for drinking, cooking and washing. In our workplaces water is used for agriculture and industry. Water provides for recreation and our need for natural beauty, and it can be part of our spiritual awareness. Water is so important and is used in so many ways that if it is overused, we risk damaging our very life source. This happens when we take too much water out of aquatic ecosystems, and put in too much waste. The South African National Water Act (NWA) (No. 36 of 1998) rec-ognises that water resources are part of the integrated water cycle made up of wa-ter ecosystems– rivers, wetlands, lakes, dams, estuaries and groundwater – and the processes of precipitation, transpiration, infiltration and evaporation. Closely con-nected to the water cycle is the use that people make of water resources. The NWA promotes protection of water resources so that people can use water both now and into the future. Water is at the heart of “a better life for all”. This handbook focuses on environmental water quality (EWQ), in particular the use of water resources for waste disposal, and the effect that waste disposal has on ecosystems. The term wa-ter quality is used to describe the microbial, physical, chemical and radiological properties of water. These properties affect both ecosystem health and the “fitness for use” of the water.
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Impact of invasive alien plants on water provision in selected catchments
- Authors: Preston, Ian R , Le Maitre, D C , Blignaut, J N , Louw, Lynette , Palmer, Carolyn G
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , report
- Identifier: http://hdl.handle.net/10962/437979 , vital:73426 , ISBN 1816-7950 , https://wrcwebsite.azurewebsites.net/wp-content/uploads/mdocs/44_04_20_33741.pdf
- Description: We analyse the impact of failing to control invasive alien plants (IAPs) on the water supply to the Berg River and De Hoop Dams, in other words, the opportunity cost of not clearing IAPs in these two catch-ments. To do this we used models to assess and compare the impact of current and future invasions on inflows into the dams. Although the clearing of current invasions would only provide a modest increase in the amount of water compared to, for example, the construction of an-other dam, failure to clear the invasion will have a negative impact on water security in the long term. We estimated that the Berg River Dam could lose up to 51% of its mean annual inflows to IAPs over a 45-year period, and the De Hoop Dam catchment could lose up to 44%. These impacts would continue to increase over time, and the costs of control could become very high as the plants invade rugged terrain. Major in-frastructural development requires Ministerial approval, supported by advice from senior officials. We suggest that such advice should sub-stantively take sufficient account of the benefits of clearing existing in-vasions, or at least of preventing further invasions. Our results suggest that serious consequences arise from insufficient investment in catch-ment management. An integrated approach to the management of the supply of and demand for water, that ensures long-term sustainability, is essential in informed decision-making and the early control of IAPs is a key component of that approach.
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Improved Photophysical and Photochemical Properties of Thiopheneethoxy Substituted Metallophthalocyanines on Immobilization onto Gold‐speckled Silica Nanoparticles
- Authors: Dube, Edith , Oluwole, David O , Nyokong, Tebello
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/187699 , vital:44688 , xlink:href="https://doi.org/10.1111/php.12879"
- Description: This work reports on the synthesis of tetrakis-[(thiophineethoxy) phthalocyaninato] indium(II) chloride (3). The photophysical behavior of complex 3 was compared to that of the Zn derivative (tetrakis-[(thiophineethoxy) phthalocyaninato] zinc(II) (complex 2)). The compounds were interacted with gold-speckled silica (GSS) nanoparticles via Au–S self assembly to afford the conjugates (2–GSS and 3–GSS). The photophysicochemical behavior of the compounds and their conjugates were assessed. The conjugates afforded a decrease in fluorescence quantum yields and lifetimes with improved triplet and singlet oxygen quantum yields in comparison with complexes 2 and 3 alone. The complexes and their conjugates could serve as good candidates for photodynamic therapy.
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In-situ synthesis of gold nanoparticles on graphene quantum dots-phthalocyanine nanoplatforms: First description of the photophysical and surface enhanced Raman scattering behaviour
- Authors: Nwahara, Nnamdi , Achadu, Ojodomo John , Nyokong, Tebello
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/187638 , vital:44682 , xlink:href="https://doi.org/10.1016/j.jphotochem.2018.04.011"
- Description: Owing to the need for new low-dimensional molecular assemblies with tailored electronic properties, the current study presents a facile approach for the synthesis and assembly of gold nanoparticles (AuNPs) onto functional graphene quantum dots (GQDs)-phthalocyanines (Pcs) arrays and the investigation of their photophysical and surface enhanced Raman scattering (SERS) properties. The GQDs were functionalized with L-glutathione (GSH) (to form GQDs@GSH) in order to assist coupling to the low symmetry Zn tris–(tert–butyl) mono carboxyphenoxy (propionic acid) phthalocyanine (complex 1) to form 1@GQDs. The affinity of gold (Au) to sulphur (S) was exploited for the assembly of the AuNPs onto 1@GQDs platform to form 1@GQDs-AuNPs. Transmission electron microscopic investigations confirmed the formation of monodispersed, spherical Pc/GQDs@GSH/AuNPs hybrids. The nanocomposite displayed high triplet quantum yields, which translated into high singlet oxygen quantum yield as high as 87%. Furthermore, the formed composites demonstrated strong surface enhanced Raman scattering (SERS) properties with an unprecedented intrinsic maximal enhancement factor of more than 30-fold. These nanostructures also retain more than 90% of their original SERS intensities after a week of storage, displaying superb stability under ambient conditions. These results highlight the remarkable potential of this composite as a unique Raman-based PDT dosimetric agent.
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In-situ synthesis of gold nanoparticles on graphene quantum dots-phthalocyanine nanoplatforms: First description of the photophysical and surface enhanced Raman scattering behaviour
- Authors: Nwahara, Nnamdi , Achadu, Ojodomo John , Nyokong, Tebello
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/188183 , vital:44730 , xlink:href="https://doi.org/10.1016/j.jphotochem.2018.04.011"
- Description: Owing to the need for new low-dimensional molecular assemblies with tailored electronic properties, the current study presents a facile approach for the synthesis and assembly of gold nanoparticles (AuNPs) onto functional graphene quantum dots (GQDs)-phthalocyanines (Pcs) arrays and the investigation of their photophysical and surface enhanced Raman scattering (SERS) properties. The GQDs were functionalized with L-glutathione (GSH) (to form GQDs@GSH) in order to assist coupling to the low symmetry Zn tris–(tert–butyl) mono carboxyphenoxy (propionic acid) phthalocyanine (complex 1) to form 1@GQDs. The affinity of gold (Au) to sulphur (S) was exploited for the assembly of the AuNPs onto 1@GQDs platform to form 1@GQDs-AuNPs. Transmission electron microscopic investigations confirmed the formation of monodispersed, spherical Pc/GQDs@GSH/AuNPs hybrids. The nanocomposite displayed high triplet quantum yields, which translated into high singlet oxygen quantum yield as high as 87%. Furthermore, the formed composites demonstrated strong surface enhanced Raman scattering (SERS) properties with an unprecedented intrinsic maximal enhancement factor of more than 30-fold. These nanostructures also retain more than 90% of their original SERS intensities after a week of storage, displaying superb stability under ambient conditions. These results highlight the remarkable potential of this composite as a unique Raman-based PDT dosimetric agent.
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Incorporation of metal free and Ga 5, 10, 15, 20-tetrakis (4-bromophenyl) porphyrin into Pluronic F127-folic acid micelles
- Authors: Managa, Muthumuni , Ngoy, Bucolome P , Mafukidze, Donovan M , Nyokong, Tebello
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/233256 , vital:50073 , xlink:href="https://doi.org/10.1016/j.jlumin.2017.09.045"
- Description: ClGa 5,10,15,20-Tetrakis (4-bromophenyl) porphyrinato (ClGaTBrPP) and its metal free derivative were successfully synthesized and incorporated into Pluronic F127 polymeric micelles that has been conjugated to folic acid (FA) to form ClGaTBrPP-F127-FA (or H2TBrPP-F127-FA). For comparison, ClGaTBrPP-F127 and H2TBrPP-F127 (without FA) were also formed. The singlet oxygen quantum yield for ClGaTBrPP-F127-FA was higher (ΦΔ = 0.44) than that of H2TBrPP-F127-FA (ΦΔ = 0.37), due to the heavy atom effect of Ga in the former which encourages intersystem crossing to the triplet state. The same applies to ClGaTBrPP-F127 (ΦΔ = 0.47) and H2TBrPP-F127 (ΦΔ = 0.41). Thus, ΦΔ values decreased in the presence of FA, but still high enough for practical application of the nanodrug system. The binding constants Kb were determined to be 1.08 × 104 M−1, 2.51 × 105 M−1, 1.52 × 103 and 2.68 × 103 for H2TBrPP+F127-FA, ClGaTBrPP+F127-FA, ClGaTBrPP-F127 and H2TBrPP-F127, respectively. The Kp values were determined in biphasic octanol and water system.
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Influence of land cover, proximity to streams and household topographical location on flooding impact in informal settlements in the Eastern Cape, South Africa
- Authors: Dalu, Mwazvita , Shackleton, Charlie M , Dalu, Tatenda
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/182089 , vital:43799 , xlink:href="https://doi.org/10.1016/j.ijdrr.2017.12.009"
- Description: Patterns of land use, household topographical location and state of natural vegetation influence the spatial distribution of flooding impact. Using field observations and GIS mapping techniques, we investigated how landscape factors influenced structural flooding impact in informal settlements. This study was carried out in the informal settlements of the Eastern Cape Province of South Africa, after the October 2012 floods. Increasing slope significantly raised the probability and level of damage by at least 30% in five of the seven sites, whereas proximity to river and wetlands (more than 100 m) was significant in only two of the sites and at lower levels. Multi-regression analysis highlighted that land cover, proximity to streams and household topographical location influenced the impact of flooding on housing structures. We found that the impact on housing structures in informal settlements during the floods were significantly influenced by their proximity to water bodies, slope factor and patterns of land cover.
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Informal urban fuelwood markets in South Africa in the context of socio-economic change
- Authors: Guild, J , Shackleton, Charlie M
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/179779 , vital:43179 , xlink:href="https://doi.org/10.1016/j.enpol.2018.03.023"
- Description: In developing countries, fuelwood is important to livelihoods and energy security because it is used for heating, cooking and can provide additional income to households through trade. The global trade in fuelwood is valued between USD 4–26 billion per annum. In South Africa, fuelwood is a widely used domestic energy source; but how that has changed with rapid urbanisation and socio-economic development over the last two decades is unknown. This study examined the presence and nature of urban fuelwood markets in 39 urban areas of the Eastern Cape and Limpopo provinces. Data were collected from 170 informal fuelwood sellers regarding the prevalence, structure, characteristics, and changes over time of the informal fuelwood markets. Over 80% of the sampled towns had an informal fuelwood market and there was a positive relationship between the number of sellers and town population size. For most sellers, the fuelwood trade was their primary occupation and the income earned was supplemented by government social grants. Sellers earned, on average, over US$9 per day. These results show that despite rapid urbanisation and socio-economic development, fuelwood remains an important domestic fuel in towns and cities of South Africa, and an income source for the urban poor.
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Integrating chemical control with sterile insect releases in an integrated pest management programme for Thaumatotibia leucotreta
- Authors: Nepgen, Eugene , Moore, Sean D , Hill, Martin P
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/423770 , vital:72092 , xlink:href="https://doi.org/10.1111/jen.12487"
- Description: False codling moth Thaumatotibia leucotreta (Meyrick) (Lepidoptera: Tortricidae) is an important indigenous pest of citrus in southern Africa. Successful control is dependent upon integration of area-wide sterile insect releases and other suppression methods. The aim of this work was to test pyrethroid and organophosphate-based insecticides (tau-fluvalinate and chlorpyrifos) for their residual effect on mortality of released irradiated T. leucotreta male moths. Both of these insecticides were effective in killing irradiated T. leucotreta for 7 days after application on leaves, after which degradation of the active ingredient resulted in a marked reduction in efficacy after 14 days and rendering them harmless. Mortality was found to be similar for irradiated and non-irradiated male T. leucotreta after treatment. Consequently, even though these insecticides might have an effect on moths in the field, ratios of sterile:wild moths should not be altered. Supporting field data from six sites in the Sundays River Valley over a season of sterile insect releases showed the conventional chemical crop protection programme to be as effective as an integrated pest management programme in facilitating effective control of T. leucotreta through sterile insect releases. The study also confirmed that the ratios of sterile:wild male moths in the commercial citrus orchards were not affected by the application of insecticides. These findings confirm the high potential of sterile insect releases for control of T. leucotreta in citrus.
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Introduction to the special issue: applied critical realism in the social sciences
- Authors: Price, Leigh , Martin, Lee
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/392133 , vital:68724 , xlink:href="https://doi.org/10.1080/14767430.2018.1468148"
- Description: The aim of our initial call for papers was to encourage the submission of exemplars of applied work, reflections on the use of critical realism, and metatheoretical developments. We were not disappointed, and we are therefore pleased to present this collection of five articles which advance our understanding of critical realism in practice. The book review in this issue further extends the collection, as it summarizes several examples of applied critical realist work. As one would expect of such a collection, there are a variety of disciplines represented, from business studies, to marketing, psychology, law and education. In this editorial, we provide an overview of the (concrete universal) trends of current applications of critical realism of which these articles are (concrete singular, and therefore unique) instantiations. Finally, we provide a brief introduction to each paper. We expect that the audience for this issue may be broader than, though still include, the usual readership of Journal of Critical Realism. Specifically, we expect to attract early career researchers who are new to critical realist ideas, and people whose primary interest is directed at one of the disciplines represented, rather than critical realism per se. For this reason, at the risk of repetition, we have allowed several of the authors to outline the aspects of critical realism that are relevant to their paper.
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Introduction: Blurring Boundaries
- Authors: Mnyaka, Phindezwa , Macleod, Catriona I
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/434252 , vital:73042 , ISBN 978-3-319-74720-0 , https://link.springer.com/chapter/10.1007/978-3-319-74721-7_9
- Description: This chapter introduces the section on blurring boundaries in research. The chapters within this section unpack the ethical dilemmas that researchers negotiate when they find themselves stepping outside their roles as researchers in the field. Research encounters presuppose particular boundaries, depending on the methodology employed and the research questions posed. However, participants may identify researchers differently, compelling them to respond in unanticipated ways as possibly therapists, clinicians, interlocutors, and activists. Collectively, the authors of the chapters in this section explore the ethical implications of blurring such boundaries. They unpack the significance of various forms of intimacies that may emerge while undertaking research, how researchers are positioned as agents of social change, and how researchers negotiate their statuses as insiders and outsiders in fieldwork.
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Introduction: The politics of anonymity and confidentiality
- Authors: Macleod, Catriona I , Mnyaka, Phindezwa
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/434237 , vital:73041 , ISBN 978-3-319-74720-0 , https://link.springer.com/chapter/10.1007/978-3-319-74721-7_15
- Description: Ethics committees standardly require that the researchers address questions concerning anonymity and confidentiality. The conventional practice is to ensure that participants’ names and identifying details are expunged from public records of the research and that high levels of confidentiality of data are maintained in the research process. In this introduction, we outline how authors of chapters in this section ask questions concerning these imperatives, including circumstances where participants actively want their identity revealed and their voice heard or when anonymising might not be possible or may further disadvantage marginalised populations. We explore the argument made by authors that the automatic anonymising of data and the imposition of confidentiality can constrain ethical conduct.
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Investigating a new wealth tax in South Africa: Lessons from international experience
- Authors: Arendse, Jacqueline A , Stack, Elizabeth M
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/69434 , vital:29536 , https://jefjournal.org.za/index.php/jef/article/view/175/193
- Description: In recent years, there has been an increasing focus on new sources of taxation, including wealth tax. In South Africa, two phenomena have driven the focus on wealth tax. Firstly, the need for additional tax revenue to fund an ongoing and growing budget deficit, exacerbated by a prolonged period of low economic growth, rising government debt and a very small base of individual taxpayers. Secondly, the fact that South Africa has one of the most unequal societies in the world. The dual demands of increased tax revenue and economic inequality have converged around wealth tax as a possible panacea to both problems. Although South Africa has a long history of wealth transfer tax in the form of estate duty and donations tax, there has never been a tax on the net wealth holdings of individuals during their lifetime. Internationally, numerous countries have used wealth tax in various forms, including inheritance tax, gift tax, recurrent wealth tax and non-recurrent wealth tax. This study examines some of the international experiences with these three categories of wealth tax, seeking lessons and experiences that can inform the debate around the viability of a new wealth tax in South Africa.
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Living in a rural community and researching HIV and AIDS: Positionality and ethics
- Authors: Akhurst, Jacqueline , van der Riet, Mary , Sofika, Dumisa
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/436907 , vital:73315 , ISBN 978-3-319-74721-7 , https://doi.org/10.1007/978-3-319-74721-7_14
- Description: The emotional impact of researching sensitive topics is under-reported. This chapter explores researcher positionality in a study of people’s management of risk in sexual activity where there is a high prevalence of HIV infection. Living in a rural community raised insider/outsider issues as the researchers participated in broader social life, adding relational and emo-tional dimensions to the process. Exploring the sensitive topic of HIV and AIDS in a resource-constrained context led to blurred boundaries as researchers also became confidante, counsellor or development worker. They were challenged by the emotional intensity of the research and related responsibili-ties, illustrating the need for enhanced ethical awareness that could not be pre-determined and highlighting the need for on-going risk assessment for both participants and researchers.
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Low symmetric metallophthalocyanine modified electrode via click chemistry for simultaneous detection of heavy metals
- Authors: Fomo, Gertrude , Nwaji, Njemuwa , Nyokong, Tebello
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/187914 , vital:44709 , xlink:href="https://doi.org/10.1016/j.jelechem.2018.02.016"
- Description: Beside different methods and materials used to develop electrochemical sensors, the modification of the electrode using click reaction based on metallophthalocyanine (MPc) compounds are shown to improve the stability and sensitivity of the sensor. This work reported the development of electrochemical sensor for mercury (II), Lead (II), copper (II) and cadmium (II) ions detection based on the synthesized novel low symmetry alkyne terminated cobalt Phthalocyanine (CoPc) derivative. Differential pulse stripping voltammetry (DPSV) technique was employed for the first time in simultaneous determination of trace levels of the above metal ions using modified glassy carbon electrode (GCE) via click chemistry. Under the optimum experimental conditions, the anodic peak current is proportional to the concentrations of metal ions over a wide range of 0 to 0.1 mM with nanolevel detection limit of 81.94, 327.71, 55.87 and 347.06 nM and the sensitivity of 866.23 ± 5.48, 215.82 ± 2.16, 1979.48 ± 11.47 and 204.50 ± 1.10 μA/mM for Hg(II), Cu(II), Pb(II) and Cd(II), respectively. The selectivity of the clicked-CoPc modified GCE toward Hg(II), Cu(II), Pb(II), Cd(II) present no interference from these metals ions. The fabricated electrochemical sensor exhibited very good electrochemical properties such as good reproducibility, stability, reusability and is suitable for the detection of heavy metal ions in tap water in our laboratory.
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Mechanisms and indicators for assessing the impact of biofuel feedstock production on ecosystem services
- Authors: Gasparatos, Alexandros , Romeu-Dalmau, Carla , von Maltitz, Graham P , Johnson, Francis X , Shackleton, Charlie M , Jarzebski, Marcin P , Jumbe, Charles , Ochieng, Caroline , Mudombi, Shakespear , Nyambane, Anne , Willis, Katherine J
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/181368 , vital:43727 , xlink:href="https://doi.org/10.1016/j.biombioe.2018.01.024"
- Description: Biofuel feedstock production can be a significant driver of landscape modification, ecosystem change and biodiversity loss. There is growing body of literature that shows how biofuel landscapes provide various ecosystem services (e.g., feedstock for fuel, carbon sequestration) and compromise other ecosystem services (e.g., food, freshwater services). These effects are context-specific and depend largely on prior land use conditions and feedstock production practices. Changes in the flow of ecosystem services due to the conversion of natural and agricultural areas can have ripple effects on human wellbeing. Despite some recent attempts to apply to biofuel settings concepts and methods rooted in the ecosystem services literature, this is the exception rather than the rule within both the biofuel and the ecosystem services research communities. This paper synthesizes the current knowledge about the impact of biofuels on ecosystem services. It focuses especially on the feedstock production phase and outlines the main mechanisms through which landscape conversion affects the provisions of ecosystem services. It proposes conceptually coherent indicators to reflect these mechanisms and offers a critical discussion of key issues at the interface of biofuels and ecosystem services.
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More than just fields: Reframing deagrarianisation in landscapes and livelihoods
- Authors: Hebinck, Paul , Mtati, Nosiseko , Shackleton, Charlie M
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/180322 , vital:43353 , xlink:href="https://doi.org/10.1016/j.jrurstud.2018.01.004"
- Description: This paper discusses the emergent properties of deagrarianisation processes in two villages in the central Eastern Cape, South Africa. The claim of is that much of the deagrarianisation literature and debate does not acknowledge the importance of landscapes and the interaction between their constituent elements, notably people, forests, grasslands, fields, grazing lands, open spaces, built environments and homesteads, all of which contribute to shaping and, in turn, are shaped by livelihoods. Conceptualising a landscape as a spatial entity and associated assemblage of practices, discourses and history, this paper dissects the landscape in terms of land uses for residential and cultural purposes, growing, grazing and gathering. These land use categories together represent the rural domain to which the villagers are attached as a place and a home. Their use of the land is not necessarily oriented to fully exploring its productive potential. The article explores the transformation from a productive landscape to one which largely hinges on consumption. The blurring of boundaries between the formally designated land use categories signifies the transformations occurring in many of the rural areas in the former homelands of South Africa.
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