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International agreement for the use and exchange of classical biological control genetic resources: a practical proposal

  • Authors: Mason, Peter G , Mc Kay, Fernando , Silvestri, Luciano C , Hill, Martin P , Weyl, Philip S R , Hinz, Hariet L , Brodeur, Jacques , Vitorino, Marcello Diniz , Barratt, Barbara I P
  • Date: 2023
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/418025 , vital:71502 , xlink:href="https://doi.org/10.1007/s10526-023-10177-7"
  • Description: The Nagoya Protocol on Access and Benefit Sharing (ABS) was implemented to further develop the third objective of the Convention on Biological Diversity, the fair and equitable sharing of benefits arising out of the utilization of genetic resources. Interpretation of this agreement is wide-ranging and there is concern that if ABS measures are poorly implemented biological control and the resultant public good will be greatly impeded. The ethos of multilateral use and exchange of genetic resources used in classical biological control will be particularly affected. In the spirit of the fair and equitable sharing of benefits arising out of the utilization of genetic resources, we propose a simple practical solution in the form of an international agreement on the use and exchange of classical biological control genetic resources.
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  • Date Issued: 2023

Know thy enemy: Investigating genetic contributions from putative parents of invasive Nymphaea mexicana hybrids in South Africa as part of efforts to develop biological control

  • Authors: Reid, Megan K , Paterson, Iain D , Coetzee, Julie A , Gettys, Lyn A , Hill, Martin P
  • Date: 2023
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/423540 , vital:72070 , xlink:href="https://doi.org/10.1016/j.biocontrol.2023.105291"
  • Description: Hybridisation of alien invasive plants complicates efforts to develop biological control, because variations in the genetic makeup of the target plant can impact the survival of host specific agents that have evolved adaptations specific to the original host. To maximise the likelihood of success in a biological control program, potential agents should therefore be collected from populations in the region of origin that are genetically similar to plants in the invaded range. Molecular markers are useful tools to understand genetic contributions in hybrid populations, especially where morphological differentiation is difficult. Nymphaea mexicana Zuccarini (Nymphaeaceae) is an invasive alien plant in South Africa that is being targeted for biological control, but hybrids with intermediate morphological traits are also present at several sites. In this study, ISSR (inter simple sequence repeats) and ITS (internal transcribed spacer) markers were used to determine which Nymphaea species are likely to be putative parents of these hybrids, and morphological characters were also investigated to determine if genetic and morphological traits matched. Two major hybrid groups were identified, with one group clustering with Nymphaea odorata Aiton and the other clustering with Nymphaea alba L. A third, smaller group clustered with Nymphaea tetragona Georgi, whereas the remaining samples clustered with pure N. mexicana from the native range. Morphological features agreed with deductions drawn from molecular data. These results allow us to focus efforts to find compatible biological control agents and better understand the complicated genetic structure of N. mexicana and Nymphaea hybrids in South Africa.
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  • Date Issued: 2023

Local peoples’ knowledge and perceptions of Australian wattle (Acacia) species invasion, ecosystem services and disservices in grassland landscapes, South Africa

  • Authors: Yapi, Thozamile S , Shackleton, Charlie M , Le Maitre, David C , Dziba, Luthando E
  • Date: 2023
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/399791 , vital:69559 , xlink:href="https://doi.org/10.1080/26395916.2023.2177495"
  • Description: Many alien tree species were introduced into grassland ecosystems in South Africa by the commercial forestry industry for paper and timber for furniture. Over decades some of these introduced species escaped into neighbouring farms and community land. Adult trees from these alien species now provide other ecosystem services, notably fuelwood. Depending on the spatio-temporal context, many of these species can also negatively affect ecosystem services. We collected interview data from commercial and communal farmers in the upper Umzimvubu catchment in South Africa to compare farmers’ knowledge and perceptions of invasive wattle species invasion and their associated ecosystem services and disservices. Fuelwood and fencing poles were the most common uses of wattle by commercial (83%; 67%) and communal (99%; 49%) farmers. On the other hand, the reduction of grass cover and loss of grazing land were the most commonly mentioned negative impacts of wattles by commercial (83%; 75%) and communal (92%; 80%) farmers. Although both groups recognise the importance of wattles in providing ecosystem services, most communal farmers perceived wattles to have more negative effects than benefits. The findings demonstrate that both farmer groups highly depend on ecosystem services and are affected by disservices of wattles. However, while large-scale commercial households favour the presence of wattles in the landscape, communal households prefer complete removal of the wattles from the landscape. This may be due to lack of locally available alternative options or inability to replace or purchase ecosystem services affected by wattles from other sources or markets like commercial farmers.
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  • Date Issued: 2023

Love at first bite? Pre-release surveys reveal a novel association between a native weevil and the invasive Nymphaea mexicana Zuccarini (Nymphaeaceae) in South Africa

  • Authors: Reid, Megan , Hill, Martin P , Coetzee, Julie A
  • Date: 2023
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/416866 , vital:71392 , xlink:href="https://hdl.handle.net/10520/ejc-ento_v31_n1_a19"
  • Description: Classical biological control aims to suppress alien invasive plant populations by introducing host-specific natural enemies from the native range. This relies on the assumption that invasive plant populations in the invaded range benefit from the release of natural enemies. Pre-release surveys in the invaded range are a useful way to determine if enemy release applies to a particular invasive alien plant, and to determine what other factors may contribute to the invasion. Similarly, pre-release surveys gather information that can be used to compare invaded sites before and after the release of biological control agents and may also identify whether natural enemies have been accidentally introduced into the country. Pre-release surveys were conducted in South Africa on the invasive Nymphaea mexicana Zuccarini (Nymphaeaceae) to gather such information about this species, for which a biological control programme is being developed. There was lower diversity and abundance of herbivores in the native range compared to South Africa, suggesting that N. mexicana does experience enemy release at most sites in South Africa. This support for the enemy release hypothesis justifies the investment in biological control for its management. However, a native weevil, Bagous longulus Gyllenhal (Coleoptera: Curculionidae), was found feeding and reproducing on N. mexicana at three sites, resulting in damage to the leaves and suggesting that a novel association has formed between these species. Bagous longulus may have potential to be distributed to sites of N. mexicana where it is not present, though further investigation is necessary to confirm if its host range is suitable for this to be a safe endeavour. With the exception of sites where B. longulus was present, leaf sizes were large and damage was low, and there is no evidence that any natural enemies have been accidentally introduced from the native range. Findings such as these emphasise the importance of conducting thorough surveys during the development of biological control programmes.
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  • Date Issued: 2023

Nagoya Protocol and Africa’s willingness to share biological control agents, are we deterred by barriers instead of using opportunities to work together?

  • Authors: Ivey, Philip J , Hill, Martin P , Voukeng, Sonia Nadege Kenfack , Weaver, Kim N
  • Date: 2023
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/418040 , vital:71503 , xlink:href="https://doi.org/10.1007/s10526-023-10184-8"
  • Description: Amongst members of the biological control community there is a range of perceptions regarding the Nagoya Protocol, at best it will hinder access to natural enemies of pests and invasive plants and at worst implementation of the Protocol will prevent access to these resources. In this preliminary study of Africa’s preparedness to implement the Nagoya Protocol and control access to potential biological control agents, we found that several countries have not yet established procedures and policies in this regard. Several factors including lack of awareness, insufficient relevant information and lack of capacity may cause delay in countries implementing access and benefit sharing legislation and processes. The lack of preparedness provides an opportunity for the research community to work with government officials to facilitate future access to natural enemies to act as biological control agents on invasive plants and agricultural pests. Collaboration between researchers, managers and bureaucrats in support of African countries could lead to collective action that develops policies and implements processes to foster exploration of African biodiversity. This collaboration could also foster the sharing of biological control agents that will benefit Africa through integrated pest management in agriculture, protection of human lives and livelihoods, and reduction of the impact of invasive alien species on biodiversity and environmental infrastructure.
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  • Date Issued: 2023

Nature-Connectedness and Well-Being Experienced During Best and Worst Times of Life: A Case for Safeguarding Biocultural Diversity

  • Authors: Møller, Valerie , Cocks, Michelle L , Vetter, Susanne
  • Date: 2023
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/426516 , vital:72359 , xlink:href="https://doi.org/10.1007/s11205-023-03063-3"
  • Description: South Africa boasts some of the richest diversity of fauna and flora in the world; it also claims to be a world in one country given its cultural diversity. In a time of climate change, rapid population growth and urbanisation, the country’s natural resources as well as its cultural diversity are under threat. We report a multi-dimensional survey conducted among Xhosa-speaking people in the Eastern Cape Province of South Africa, that collected detailed information on indigenous knowledge of nature and its impact on cultural practices and well-being. Survey respondents included both rural and urban dwellers, a majority of whom professed to be Christians who also held traditional religious beliefs and acknowledged the ancestors. Survey respondents described their Best and Worst periods of life in line with Bernheim’s Anamnestic Comparative Self-Assessment, and indicated whether going into nature had contributed to their Best life experience and helped them to cope during their Worst one. Being in nature typically contributed to well-being across many of the Best social domains of life, such as celebrations with family, personal achievements and milestones in life, including traditional rites of passage to adulthood. Deaths in the family represented by far the most common Worst experience in life when going into nature often provided comfort and solace. Findings suggest that experience of the multiple benefits of being in nature may be universal across cultures and that many traditional Xhosa religious beliefs and cultural practices go hand in hand with access and exposure to nature that enhances well-being.
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  • Date Issued: 2023

Performance and field host range of the life stages of Cornops aquaticum, a biological control agent of water hyacinth

  • Authors: Franceschini, M Celeste , Hill, Martin P , Fuentes-Rodríguez, Daniela , Gervazoni, Paula B , Sabater, Lara M , Coetzee, Julie A
  • Date: 2023
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/424814 , vital:72186 , xlink:href="https://doi.org/10.1111/eea.13354"
  • Description: Host specificity determination of weed biocontrol agents has historically relied on evidence generated through quarantine trials in the region of introduction. These trials could give ‘false positive’ results due to a maximum type I error probability, and where possible, more research under field conditions should be conducted in the region of origin. The oligophagous, semiaquatic grasshopper, Cornops aquaticum Bruner (Orthoptera: Acrididae, Tetrataeniini), was released in South Africa for the biological control of Pontederia crassipes Pellegrini and Horn (Pontederiaceae). The aim of this study was to assess how the performance and field host range of C. aquaticum varies according to its stages of development, and how this contributes to the understanding of the relationship between the fundamental (laboratory-based) and the ecological (field-based) host range of this grasshopper, and its implications for water hyacinth biocontrol. We conducted post-release laboratory no-choice trials, confining early instars (instars 1 and 2), later instars (instars 3–6), and adult females and males in mesh cages, to determine insect performance on wetland plants growing in sympatry with P. crassipes. Also, gut analysis from field-collected C. aquaticum was done to determine the ecological host range of this insect, identifying epidermal tissue of consumed plants. In no-choice trials, survival rates of the later instars and adult C. aquaticum were similar on Pistia stratiotes L. (Araceae), Oxycaryum cubense (Poepp. and Kunth) Lye (Cyperaceae), and P. crassipes. However, under field conditions, P. crassipes and the congeneric Pontederia azurea Sw. were the only plant contents in the guts of early instars and the most abundant species in later instars and adults. The results support the hypothesis that C. aquaticum is an oligophagous insect on the genus Pontederia, and that different life stages should be considered when conducting host-specificity trials in externally feeding mobile herbivore species. Diet composition of field-collected insects thus could help detect false positives in laboratory trials, being an additional and realistic approach in understanding and predicting the selection processes of the insect in the new environment. Retrospective analysis of potential agents that were rejected due to lack of host-specificity, using the methods from this study, could add a suite of additional agents to programs where invasive weeds remain unmanaged.
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  • Date Issued: 2023

Photoantimicrobial activity of Schiff-base morpholino phthalocyanines against drug resistant micro-organisms in their planktonic and biofilm forms

  • Authors: Sindelo, Azole , Sen, Pinar , Nyokong, Tebello
  • Date: 2023
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/360437 , vital:65088 , xlink:href="https://doi.org/10.1016/j.pdpdt.2023.103519"
  • Description: Antimicrobial photodynamic inactivation (aPDI) is a treatment for the eradication of drug-resistant micro-organisms. One of the advantages of this technique, is that there is minimal possibility of microbial resistance. Hence, herein, the preparation and characterization of novel neutral and cationic morpholine containing Schiff base phthalocyanines are reported. The cationic complexes gave moderate singlet oxygen quantum yields (ΦΔ) of ∼0.2 in aqueous media. Conversely, the neutral complexes generated very low ΦΔ values making them very poor candidates for antimicrobial studies. The cationic phthalocyanines showed excellent photodynamic activity against planktonic cells of all micro-organisms (Candida albicans, Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus, Salmonella enterica subspecies enterica serovar Choleraesuis, vancomycin-resistant Enterococcus faecium, and methicillin-resistant Staphylococcus aureus). The efficiency of aPDI was shown to be both concentration and light-dose-dependent. Mono biofilms were susceptible when treated with 200 µM of cationic Pcs at 108 J/cm2. However, ∼10% of the mixed biofilm survived after treatment.
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  • Date Issued: 2023

Photodynamic inactivation of methicillin-resistant Staphylococcus aureus using pyrrolidinium containing Schiff base phthalocyanines

  • Authors: Sindelo, Azole , Sen, Pinar , Nyokong, Tebello
  • Date: 2023
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/360449 , vital:65089 , xlink:href="https://doi.org/10.1016/j.jphotochem.2022.114535"
  • Description: New tetra-substituted zinc and indium Schiff base phthalocyanines (ZnPc and InPc, respectively) are synthesized and characterized herein. The ethyl pyrrolidine (ZnPc-2, InPc-2) and propyl pyrrolidine (ZnPc-3, InPc-3) substituted Schiff base Pcs were reacted with methyl iodide to form their cationic derivatives (ZnPc-2Q, InPc-2Q, ZnPc-3Q, and InPc-3Q, respectively). The photophysical and photochemical properties of the Pcs were studied. The cationic Pcs generated higher singlet oxygen quantum yield in aqueous media than the neutral Pcs. The photoinactivation of Methicillin-resistant Staphylococcus aureus (MRSA) and Methicillin-sensitive Staphylococcus aureus (MSSA) strains was evaluated. 5 µM ZnPc-3Q and InPc-3Q inactivated 100 % of the MSSA and MRSA while 5 µM ZnPc-2Q and InPc-2Q eradicated 100 % for MSSA and 97.2 % and 98.7 % (respectively) of the MRSA. The photodynamic antimicrobial chemotherapy studies depended on singlet oxygen ability, the charges, and the extension of the alkyl groups.
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  • Date Issued: 2023

Signposts on the road toward transformative governance: how a stronger focus on diverse values can enhance environmental policies

  • Authors: Keleman, Eszter , Subramanian, Suneetha M , de Vos, Alta , Amaruzaman, Sacha , Porter-Bolland, Luciana , Islar, Mine , Kosmus, Marina , Nakangu, Barbara , Nuesiri, Emmanuel , Robles, Gabriela A , Yiu, Evonne , Emerton, Lucy , Zólyomi, Ágnes
  • Date: 2023
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/415927 , vital:71301 , xlink:href="https://doi.org/10.1016/j.cosust.2023.101351"
  • Description: Transformative change toward sustainability is increasingly recognized as inevitable to avoid the collapse of socioecological systems. However, for a deep and system-wide transformation, governance approaches and policymaking need to be changed too. This paper discusses how a diverse value approach in environmental policymaking could be undertaken to foster transformative governance that can further lead to system-wide transitions. Based on the analysis of different policy options’ transformative potential, we argue that the more diverse values addressed by a policy instrument, the bigger its transformative potential. Weaving values into policy decision-making is possible at several junctures of the policy process, but context-specificities should always be considered, and capacities must be enhanced at all levels, both for public and private actors.
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  • Date Issued: 2023

Social innovation that connects people to coasts in the Anthropocene

  • Authors: Celliers, Louis , Costa, Maria M , Rölfer, Lena , Aswani, Shankar , Ferse, Sebastien
  • Date: 2023
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/391410 , vital:68649 , xlink:href="https://doi.org/10.1017/cft.2023.12"
  • Description: Post-industrial society is driving global environmental change, which is a challenge for all generations, current and future. The Anthropocene is the geological epoch in which humans dominate and it is rooted in the past, present, and future. Future sustainability is building on the momentum of the fundamental importance of studying human dynamics and governance of coupled social and ecological systems. In the Anthropocene, social innovation may play a critical role in achieving new pathways to sustainability. This conventional narrative review uses a qualitative analysis anchored in the Grounded Theory Method and a systematic collection and analysis of papers to identify broad types of social innovations. Scientific journal articles published since 2018 were prioritised for inclusion. The six types of social innovation proposed are (a) authentic engagement; (b) artful and engaging communication; (c) urging and compelling change; (d) governance for social-ecological systems; (e) anticipation in governance; and (f) lived experiences and values. The six innovations proposed in this paper can be embedded within, and form part of, social action using a science–society compact for the sustainable development of coasts in the Anthropocene.
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  • Date Issued: 2023

Socio-Economic and Environmental Challenges of Small-Scale Fisheries: Prognosis for Sustainable Fisheries Management in Lake Kariba, Zambia

  • Authors: Imbwae, Imikendu , Aswani, Shankar , Sauer, Warwick H H
  • Date: 2023
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/391422 , vital:68650 , xlink:href="https://doi.org/10.3390/su15043179"
  • Description: The Lake Kariba fishery is of regional importance; it accounts for 35% of the total Zambian fish production. However, emerging evidence in the recent decades suggests that the fishery is facing socio-economic and environmental challenges. Using Ostrom’s framework for analysing socio-ecological systems, we examined the social, economic, and environmental problems faced by the fishing communities in Lake Kariba. The framework links various social, economic, and ecological factors to devise a sustainable fisheries management plan. A combination of survey questionnaires, focus group discussions, observations, and key informant interviews were used to assess this sustainability challenge. The data collected were subjected to bivariate and descriptive analysis. The results obtained did not show a significant decline in fish production over the past 13 years (R2 Linear = 0.119, p = 0.248). However, the experts and the fishers have reported declining trends in valuable fish species such as Oreochromis mortimeri, compounded by the increased fishing efforts (X2 = 180.14, p value = ˂ 0.00001). The key threats identified include: overfishing, weak institutions, and the introduction of invasive fish species such as Oreochromis niloticus. This situation has raised fears of fish depletion among the stakeholders. Based on these results, we recommend stronger institutional collaboration among the stakeholders in the riparian states and education that illustrates the global value of fisheries for food security and biodiversity conservation in pursuing the United Nations Sustainable Development Goals.
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  • Date Issued: 2023

Socioeconomic and geographic variations in antenatal care coverage in Angola: further analysis of the 2015 demographic and health survey

  • Authors: Shibre, Gebretsadik , Zegeye, Betregiorgis , Idriss-Wheeler, Dina , Ahinkorah, Bright Opoku , Oladimeji, Olanrewaju , Yaya, Sanni
  • Date: 2023
  • Subjects: Prenatal care , Mothers -- Mortality , Health surveys
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/11260/4489 , vital:44125 , https://doi.org/10.1186/s12889-020-09320-1
  • Description: In African countries, including Angola, antenatal care (ANC) coverage is suboptimal and maternal mortality is still high due to pregnancy and childbirth-related complications. There is evidence of disparities in the uptake of ANC services, however, little is known about both the socio-economic and geographic-based disparity in the use of ANC services in Angola. The aim of this study was to assess the extent of socio-economic, urban-rural and subnational inequality in ANC coverage in Angola. We analyzed data from the 2015 Angola Demographic and Health Survey (ADHS) using the World Health Organization (WHO) Health Equity Assessment Toolkit (HEAT) software. The analysis consisted of disaggregated ANC coverage rates using four equity stratifiers (economic status, education, residence, and region) and four summary measures (Difference, Population Attributable Risk, Ratio and Population Attributable Fraction). To measure statistical significance, an uncertainty interval (UI) of 95% was constructed around point estimates. The study showed both absolute and relative inequalities in coverage of ANC services in Angola. More specifically, inequality favored women who were rich (D = 54.2, 95% UI; 49.59, 58.70, PAF = 43.5, 95% UI; 40.12, 46.92), educated (PAR = 19.9, 95% UI; 18.14, 21.64, R = 2.14, 95% UI; 1.96, 2.32), living in regions such as Luanda (D = 51.7, 95% UI; 43.56, 59.85, R = 2.64, 95% UI; 2.01, 3.26) and residing in urban dwellings (PAF = 20, 95% UI; 17.70, 22.38, PAR = 12.3, 95% UI; 10.88, 13.75). The uptake of ANC services were lower among poor, uneducated, and rural residents as well as women from the Cuanza Sul region. Government policy makers must consider vulnerable subpopulations when designing needed interventions to improve ANC coverage in Angola to achieve the 2030 Sustainable Development Goal of reducing global maternal mortality ratio to 70 deaths per 100,000 live births.
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  • Date Issued: 2023

The concurrent impacts of drought and leaf harvesting on two traditional African vegetable non-timber forest product species

  • Authors: Sinasson, Gisele K , Shackleton, Charlie M
  • Date: 2023
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/399832 , vital:69562 , xlink:href="https://doi.org/10.1371/journal.pone.0283900"
  • Description: Investigating the concurrent impacts with harvesting on wild vegetables can guide their sustainable management while contributing to the understanding of such impacts on NTFP species. This study investigated leaf production, morphological and growth responses to the concurrent impacts of drought and leaf harvesting between two wild vegetables. A randomized greenhouse experiment was implemented with 1,334 plants of Amaranthus sp. and 391 of B. pilosa. A drought treatment was first implemented through six levels of drought stress and a control treatment. The harvesting treatment consisted of four harvesting levels and was implemented twice. Measurements were recorded before first and second harvests and at end of experiment. Data were separated into two periods (after first and second harvests) and analyzed using Multivariate Analysis of Variance and log-linear analysis. The results showed significant effects of drought on both species. However, Amaranthus sp. appeared more resilient to reduction in the daily amount of water than reduction in the frequency, while B. pilosa was resilient under both facets of drought stress. For Amaranthus sp., basal diameter, its growth, leaf production and survival increased with increase in the harvesting level (with some exceptions) after first harvest. After second harvest, there was decrease in plant height and leaf production. In B. pilosa, the impact was only significant on survival and leaf production (after first harvest). The effect of the interaction of the two drivers was significant for Amaranthus sp., but not for B. pilosa. The results also highlighted the possible negative impact of a prolonged high rate harvesting on the species performance, especially under severe drought. Basal diameter, its growth, survival and leaf production appeared more resilient to reduced amounts of watering in Amaranthus sp., and under both types of drought stress for B. pilosa. This suggests that both species could be sustained under medium drought stress.
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  • Date Issued: 2023

The importance of long-term post-release studies in classical biological control: Insect–plant monitoring and public awareness of water hyacinth management (Pontederia crassipes) in Dique Los Sauces, Argentina

  • Authors: Faltlhauser, Ana C , Jiménez, Nadia L , Righetti, Tomas , Visintin, Andrés M , Torrens, Javier , Salinas, Nicolás A , Mc Kay, Fernando , Hill, Martin P , Cordo, Hugo A , Sosa, Alejandro J
  • Date: 2023
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/424828 , vital:72187 , xlink:href="https://doi.org/10.1111/eea.13355"
  • Description: Several components of classical biological control (CBC) programmes are necessary to assess the success of the management strategy (e.g., post-release monitoring) and also help prevent reintroductions or resurgences of invasive species (e.g., public awareness). Water hyacinth, Pontederia (= Eichhornia) crassipes (Mart.) Solms (Pontederiaceae) is an aquatic plant naturally distributed in the north-eastern region of the Del Plata basin in Argentina. In the 1960s it was introduced into the Dique Los Sauces reservoir located outside of its native range in La Rioja Province, in western Argentina, where it became invasive. The natural enemy, Neochetina bruchi Hustache (Coleoptera: Curculionidae), was intentionally introduced in 1974 to control the weed. To assess the success of this CBC programme, a long-term post-release study was conducted. Between 1965 and 2023, we monitored plant coverage, estimated N. bruchi densities, and quantified the associated damage by reanalysing previously published data and incorporating new sampling. We also conducted an online survey to analyse public knowledge and perception about this programme. Water hyacinth coverage fluctuated from its first record in 1965 (maximum coverage 90%) until the control of germinated plants (coverage 0%) in 2018. The plant decline was accompanied by an increase in the weevil population. In our survey, out of 325 respondents only a small group of mostly middle-aged and elderly people knew that the restoration had been achieved through a management strategy and even fewer were aware of the biocontrol approach taken. Respondents who had a positive approach to biological control were more aware of the management plan than respondents who had neutral or negative opinions. Neochetina bruchi has played a key factor in the control of P. crassipes. The intrinsic dynamics of these populations, the dormant seed bank, and the lack of public awareness support the need for long post-release evaluations including outreach campaigns to make a sustainable successful management programme.
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  • Date Issued: 2023

The in-vitro proliferation-suppression of MCF-7 and HeLa cell lines mediated by differently substituted ionic phthalocyanines in sonodynamic therapy supplemented-photodynamic therapy

  • Authors: Nene, Lindokuhle Cindy , Nyokong, Tebello
  • Date: 2023
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/360461 , vital:65090 , xlink:href="https://doi.org/10.1016/j.jinorgbio.2022.112084"
  • Description: This work focuses on the study of the effects of the ultrasonic frequency (MHz) and power (W.cm−2) on the stability, reactive oxygen species yields and cytotoxicity activities of differently substituted ionic phthalocyanines (Pcs) in sonodynamic therapy (SDT). Four ultrasonic parameters were investigated: Par I (1 MHz: 1 W.cm−2), Par II (1 MHz: 2 W.cm−2), Par III (3 MHz: 1 W.cm−2) and Par IV (3 MHz: 2 W.cm−2). A higher degradation of the Pcs was observed with increasing power at the Par II. Two reactive oxygen species (ROS) were detected in the ultrasound treated Pcs: singlet oxygen and hydroxyl radicals. Due to minimal degradation of most Pcs, Par I was chosen for SDT, photodynamic therapy (PDT), and photo-sonodynamic therapy (PSDT) against Michigan Cancer Foundation-7 and Henrietta Lacks cancer cell lines. PSDT generally showed improved therapeutic efficacies of the Pcs compared to the SDT and PDT mono treatments.
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  • Date Issued: 2023

The prevalence, uses and cultural assimilation of shrub and tree invasive alien plants in a biodiversity hotspot along the Wild Coast, South Africa

  • Authors: Wootton, Oscar , Shackleton, Charlie M
  • Date: 2023
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/401314 , vital:69725 , xlink:href="https://doi.org/10.1080/26395916.2023.2216804"
  • Description: Invasive alien plant species (IAPS) frequently offer both ecosystem services and disservices to rural communities with high livelihood dependency on local landscapes. However, biocultural relationships with IAPS may go deeper than just provisioning uses, as they may be assimilated into local belief systems manifest in them becoming embedded in cultural constructions such as naming, stories, songs and ceremonies. It is likely that IAPS that are culturally assimilated will represent a greater conflict of interest in the face of proposed controls of IAPS in biodiversity hotspots where conservation priorities are frequently deemed paramount by external agencies. Using a mixed-methods approach we undertook roadside surveys of 17 selected IAPS along the 250 km Wild Coast section of the Maputaland-Pondoland-Albany biodiversity hotspot, accompanied by questionnaire interviews with 48 local people. The mean number of IAPS per site was four, ranging from zero (only one site) to ten, and local inhabitants deemed the abundance of all but one of the species to be increasing. All species had been in the region for decades, had a vernacular name, and all but one had direct consumptive uses. Species with multiple uses were more widely recognised. However, there was only marginal incorporation of the IAPS into stories, songs and ceremonies, although medicinal uses of some IAPS were for cultural/spiritual needs rather than physical ailments per se. These results show that despite widespread use, there was as yet relatively limited cultural assimilation of the IAPS in the Wild Coast region.
  • Full Text:
  • Date Issued: 2023

The Southern African Program on Ecosystem Change and Society: an emergent community of practice

Transboundary Fisheries Management in Kavango–Zambezi Transfrontier Conservation Area (KAZA-TFCA): Prospects and Dilemmas

  • Authors: Imbwae, Imikendu , Aswani, Shankar , Sauer, Warwick H H , Hay, Clinton
  • Date: 2023
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/391433 , vital:68651 , xlink:href="https://doi.org/10.3390/su15054406"
  • Description: Inland fisheries in the Kavango–Zambezi Transfrontier Conservation Area (KAZA-TFCA) offer food security to the riverine communities across the region. They also contribute towards the attainment of the United Nations’ Sustainable Development Goals 1 and 15, which aim to alleviate poverty and maintain biodiversity conservation. Despite this significant role, the fisheries have suffered severe declines in the previous decades due to multiple factors, such as overfishing and poor legislation. Furthermore, climate change is exerting pressure by altering the ecology and productivity of the river systems. The unprecedented challenges of the COVID-19 pandemic have further constrained management efforts. Attempts to address these challenges have pointed towards transboundary fisheries management as a silver bullet in moving towards sustainable fisheries management. However, the implementation of this strategy in the region has encountered numerous roadblocks, thereby subjecting the river ecosystem to a wider environmental threat, with dire consequences on livelihoods. This paper reviews existing management and governance structures together with key informant interviews to elicit primary and secondary data essential for management at the regional level. The study identifies conflicting regulations, and inadequate policies and institutions across the region as major bottlenecks affecting the successful implementation of transboundary fisheries management. Finally, the paper offers some suggestions for the improvement of fisheries management in the region.
  • Full Text:
  • Date Issued: 2023

TVET SI: Evaluating Boundary Crossing Social Learning in Vocational Education and Training: A value creation approach

  • Authors: Lotz-Sisitka, Heila , Sisitka, Lawrence , Chakona, Gamuchirai , Matiwane, Mandilive L , Matambo, Chamu
  • Date: 2023
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/389925 , vital:68495 , xlink:href="https://www.ajol.info/index.php/sajee/article/view/238540"
  • Description: This article focuses on the development and application of an evaluation model and approach for evaluating boundary crossing social learning in a Vocational Education and Training (VET) learning network in South Africa, with an emphasis on a Training of Trainers (ToT) course that helped to catalyse and strengthen this learning network via two iterations of the course over an eight-year period. The article shares how we adapted the value creation framework (VCF) of Wenger, Traynor and De Laat (2011; Wenger and Wenger-Traynor, 2020) in the evaluation of a VET Training of Trainers (ToT) programme and learning network that focussed on the uptake and circulation of rainwater harvesting and conservation (RWHandC) knowledge in a particular formal and informal VET context in the Eastern Cape, South Africa, where smallholder farmers were struggling to find water for producing food. The evaluated ToT course was catalytic in establishing a boundary crossing social learning network approach in a VET context that linked formal and informal VET (Lotz-Sisitka et al., 2016; Lotz-Sisitka et al., 2022; Pesanayi, 2019); hence we found it important to develop adequate tools for its evaluation. The focus of this article is to share how we developed an evaluation approach to this work. We share insights on the indicators developed for diff erent types of value created, and also insights gained into the use of this evaluation approach in a boundary crossing VET social learning project that took a ToT course as focus. In short, evaluation findings show that the boundary crossing ToT course off ers strong immediate, potential and applied value that can lead to realised and reframed value, especially if supported by ongoing learning network activities that follow the initial engagement in the boundary crossing ToT course. Th is leads, over time, to transformative value which is important in achieving the overall objective of such social learning, namely making knowledge more co-engaging, accessible and useful in the context where improved food security via better use of rainwater harvesting and conservation amongst smallholder farmers and household food producers is a necessary form of sustainable development. Orientation value, and enabling value were found to be vital for the emergence of other kinds of value. The evaluation model also allows for the lifting out of strategic value which points to wider uptake potential. All this creates the possibility for indicator development that can help inform iterative development of boundary crossing VET courses used to stimulate the co-construction of learning networks and ongoing social learning for sustainable development.
  • Full Text:
  • Date Issued: 2023
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