Browsing by Author "O'Farrell, Patrick"

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    Open Access
    An assessment of critical carbon services and water resources in South Africa’s terrestrial protected area network
    (2022) Plaistowe, Jonathan; Foden, Wendy; O'Farrell, Patrick; Hoffman, Michael
    Conservation planning can more greatly emphasise the importance of considering ecosystem services alongside biodiversity features to improve the planet's climate change resilience. Protected Areas (PAs) are a form of area-based conservation that successfully protects biodiversity and may conserve ecosystem services important for societal climate change resilience. This study assesses the performance of South Africa's protected area network in protecting strategic carbon and water services, which are important for climate change resilience. My first question investigated how well the country's PAs perform regarding the area coverage of carbon stocks and Strategic Water Source Areas (SWSA). My second question investigated whether the country's PAs have effectively protected the carbon stocks inside their borders. I hypothesised that the carbon stock values would be higher in PAs, given that PAs have successfully prevented the loss of natural land cover inside their borders. I also compared the effectiveness of PAs in protecting carbon stocks in terms of their management authority, province and land cover classes. I used existing datasets of PAs, environmental variables, SWSAs and carbon stocks for this study. Using the total organic carbon (TOC) and South Africa's Natural Land Cover, I calculated natural Strategic Total Organic Carbon Areas (STOCA). Then I used the STOCAs and SWSAs to assess the PA coverage of these two strategic ecosystem service areas and their overlapping areas. For the second question, I investigated the carbon stock values inside and outside PAs while controlling for environmental variables. I also investigated the effect of natural land cover, provincial designations and management authorities. Results indicate that South Africa's PAs cover 9.8% of the country's mainland but protect 14.8% of SWSAs, 21.7% of STOCAs and 28.5% of the SWSA & STOCA areas. The PAs have greater TOC, Total Soil Organic Carbon (TSOC) and Total Biomass Organic Carbon (TBOC) values inside their borders than outside. Natural areas inside PAs are higher in TOC, TSOC and TBOC values than outside natural or transformed areas. These results provide evidence that South Africa's PAs are effectively protecting their carbon stocks. Therefore, there is evidence that PAs are important for climate change mitigation and may be important for Nature-based Solutions (NbS) in increasing climate change resilience. Eastern Cape, KwaZulu-Natal, Limpopo, and Western Cape PAs should be studied to improve other PAs' management. Although the PA network is strategically placed to protect the country's ecosystem service areas, the extent of this protection is short of international PA targets. There are many more strategic ecosystem service areas available for protection. Considering the effectiveness of Eastern Cape and KwaZulu-Natal PAs and the availability of strategic ecosystem service areas for protection, policy-makers and conservation managers should consider these provinces for PA expansion. Limpopo should also be considered for PA expansion, given the high carbon stock values outside PAs. This study shows the importance of South Africa's protected area network for climate change resilience and provides information on where its necessary expansion can best be planned for. It also offers a potential set of metrics and targets for monitoring in the future.
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    Open Access
    The effects of invasive alien plants on cultural ecosystem services : tourism and recreation
    (2011) Davey, Jared; Anderson, Pippin; O'Farrell, Patrick
    With the continued spread of invasive alien vegetation in South Africa, there is a growing need and recognition in protecting ecosystem service delivery. While most literature on ecosystem services has focussed on provisioning and supporting services, this study looks at the less addressed cultural ecosystem services, specifically focussing on tourism and recreation. This research explores the relationship between tourism and invasive alien vegetation. This was carried out at firstly a national level, utilising primarily quantitative methods to identify, and map alien vegetation overlaps with key tourist sites in South Africa. This was followed by a more in-depth qualitative analysis, at a case study level, focussed on the Stellenbosch municipality, to determine the understanding and perceptions, tourists, landowners, and tourism operators have regarding invasive alien plants. Moderate to high levels of infestation were found overlapping various key tourism destinations across the country. The most heavily impacted provinces include the Western Cape, Eastern Cape, and KwaZulu-Natal. In certain areas, invasion levels at key tourist destinations raise concerns regarding the management of these sites. The findings of this research signify a close link and definite relationship between tourism, and invasive alien vegetation. Looking specifically at tourism as a cultural ecosystem service, and the relationship this service has with invasive alien vegetation, future studies need to recognise the significance of this association, while the broader tourism industry needs to recognise the potential threats invasive alien vegetation poses to their operations. Furthermore, this research identifies the value in combining qualitative, human dimensions, with quantitative data and mapping approaches in ecosystem services research.
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    Open Access
    Exploring the ecological and social benefits of the Khayelitsha Wetlands Park
    (2017) Mathenjwa, Fezile; Anderson, Pippin; O'Farrell, Patrick
    In a world confronted by rapid urbanization linked with dramatic population growth rates, there is a general consensus that quality urban green spaces are important components of urban landscapes. Urban green spaces are defined as open spaces in urban areas primarily covered with vegetation, which are available to users within the community. They have the ability to shape the image of cities and provide various important socioecological benefits, which can contribute to improving the quality of life within these urban communities. In Cape Town, the provision of readily accessible quality urban green spaces is often overridden by other conflicting demands, such as biodiversity conservation and infrastructure development demands. The literature suggests that Cape Town has ample available green spaces. However, the accessibility of this green space is linked to issues of poor management and maintenance, and as a result poor urban spaces are often associated with criminal activities, and are therefore unavailable to benefit urban communities. This is particularly evident in areas which have a low socioeconomic status. This study explores the ecosystem services offered by the Khayelitsha Wetlands Park in the Khayelitsha Township on the Cape Flats. A variety of methods were used to establish the condition of the Wetlands Park and assess the impacts of various uses (e.g. recreation, agriculture etc.) on the vegetation structure and water quality. Qualitative semi-structured interviews were also conducted to assess the local community's uses and perceptions of this green space. A Complex Adaptive Landscape (CAL) approach was adopted to derive the positive and negative social-ecological impacts of the Khayelitsha Wetlands Park. The vegetation structure assessment results showed a dominance of emergent and invasive vegetation, such as Typha capensis and Acacia cyclops, and indicates a high level of degradation and a lack of indigenous vegetation species. The water quality analysis reveals high concentrations of physiochemical and microbial pollutants, where a majority exceeded the Targeted Water Quality Ranges (TWQR) recommended by the Department of Water Affairs for livestock watering, irrigation and human use. Findings from the semi-structured interviews, revealed that a majority of users v visit the Park for multiple activities offered by the Park. These include relaxation, creating and maintaining social relations, sports and recreation and agricultural use. The CAL framework revealed negative and positive feedback mechanisms at play in this urban green space. The negative feedback effects are illustrated and confirmed by poor water quality and a predominantly alien infested vegetation structure. The poor ecological condition of the Wetland is linked to a number of anthropogenic influences, including the discharge of treated waste and untreated waste from both agricultural and urban waste sources, indicating the complexity of managing the Khayelitsha Wetlands Park. Since a number of users and management institutions are connected to the Khayelitsha Wetlands Park, their involvement in the management thereof is crucial for effectively solving the issues identified.
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    Testing the water: How communities value, use, impact and manage water-related ecosystem services originating in an urban protected area
    (2017) Brill, Gregg; Anderson, Pippin; O'Farrell, Patrick
    Freshwater ecosystems and their associated landscape features found in developing cities and urban protected areas are essential components of urban social-ecological systems providing city residents with cultural, provisioning and regulating services, all of which hold value. Understanding these values requires overcoming conceptual and methodological challenges so that the multi-dimensional nature, relating to the varying values, benefits, and trade-offs are understood. Understanding values, benefits and trade-offs is essential for ensuring informed and effective management of these services and the landscapes that provide them. This requires the development of tools and methods to predict how changes in land-use and management practices might affect the provision of such services. This study contributes to both the methodological and empirical literature by developing integrated and multidisciplinary approaches to assessing the beneficiaries of freshwater ecosystem services in an urban context and recognising the ecological, social and economic values assigned to ecosystem services over multiple spatial and temporal scales. The aim of this thesis was to assess how beneficiaries, stakeholders and managers within a developing city context, recognise, value and manage the multiple diverse ecosystems services associated with freshwater ecosystems as provided by different landscape features originating in an urban protected area. This aim was achieved by establishing who the beneficiaries of freshwater ecosystem services are, uncovering the spatial and temporal relationships these beneficiaries have with landscape features, determining the nature of ecosystem service values, benefits, impacts and trade-offs as experienced by the different users, as well as analysing the management policies and practices associated with urban ES. Drawing on accumulated as well as existing data sets, newly developed methods and approaches were implemented in this study. This work was primarily undertaken in Table Mountain National Park and in Cape Town, South Africa. A comparative analysis of the perceptions of park managers toward ecosystem service governance and management was undertaken in Table Mountain National Park and in Tijuca National Park, in Rio de Janeiro, Brazil. Natural freshwater ecosystems (e.g. rivers), particularly when combined with built infrastructure (e.g. dams), provide highly valued features in landscapes, delivering multiple cultural services to city residents. Recreation, aesthetic and existence services were valued highest by respondents. People who live closer to the park use, and benefit from, the park's freshwater ecosystems more frequently than those living further away. Park visitors want ease of access in terms of distance to specific freshwater ecosystems, and then once there they want a diversity of activity options, such as recreation opportunities as well as places to reflect and meditate. The outcomes of the cultural-service study in this thesis have important management implications where insights gained can guide management to ensure equitable and sustainable ecosystem service provision to all city residents. To enhance the management of ecosystem services in urban protected areas, it is important to understand the level of inclusion of the ecosystem-service concept in park policy and daily practice. Although management perceptions correspond well with park policy, the concept of ecosystem services is still narrowly developed and needs to be better integrated into the management structures and activities of Table Mountain National Park and Tijuca National Park. Outcomes from this study show that management attention relating to fresh water is still primarily focussed on biodiversity conservation and maintaining system processes and functions. Implementing and enacting the ecosystem services concept largely still needs to happen within parks and urban interfaces. The lack of communication between managers and stakeholders of protected areas makes identifying the beneficiaries of fresh water and valuing ecosystem services difficult, especially when water and associated services flow outside of the park boundaries. An important component of this study was to determine the changes to ecosystem service provision as fresh water flows from a protected area into and across an urban landscape. A scoring system was developed to determine whether changes in land use along three case-study rivers in Cape Town, all of which originate in Table Mountain National Park, positively or negatively impact the provision of water-related ecosystem services. Changes in service provision, over time, were compared to changes in long-term water quality data to verify results from the scoring system. Generally, service levels increased over time along the upper river reaches, whereas the middle and lower reaches of the rivers showed overall declines. The changes to service provision influence the value that urban residents assign to rivers. Findings in this study suggest that the provision of cultural ecosystem services as well as the protection of biological diversity were the key factors considered by those living along the case study rivers as reasons for being willing to pay to protect rivers. Provisioning services were shown to be of less value, as were the economic contribution to property values based on river frontage. This study supports the call for more innovative research to be undertaken in developing countries to break new ground and provide more comprehensive analyses to further our understanding of the values of urban ES. The challenge for environmental researchers in this context is to intensify efforts to understand the relationships between specific landscape elements and freshwater ecosystems and human perceptions, feelings and interpretations, and to express these relationships in ways that are useful for environmental policy and management.
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    The effects of urbanisation on bee and wasp communities in Cape Town, South Africa
    (2022) Walker, Gemma; Janion-Scheepers, Charlene; Brom, Peta; O'Farrell, Patrick
    Bees and wasps provide essential regulatory ecosystem services by pollinating urban plants. However, there are massive global declines in many insect groups, and little is known about the impacts of urbanisation on pollinators in rapidly developing areas of Africa. South Africa is one of the most urbanised and biodiverse countries in Africa, and the Cape Floristic Region, one of the country's most important centres of biodiversity, is the only area in the world where bee and plant diversity hotspots coincide. Within the centre of this hotspot (Durbanville, Cape Town), I investigated the effects of urbanisation and availability of floral resources on bee and wasp (pollinator) diversity, community composition, and nesting guild distribution across an urbanrural/natural gradient. Using pan traps, specimens were collected from 18 sites in the austral spring of 2019 and 2020. A total of 433 bee and 45 wasp specimens, comprising of 45 bee and 27 wasp morphospecies respectively, were collected. Bees from the family Halictidae (particularly Seladonia and Patellapis species) were the most abundant. Except for Apis mellifera, all other bee species were solitary, and most (86.7%) collected pollen from flowers. A total of four different nesting guilds were identified, with the most common being ground-nesters (68.9%). Floral resources, rather than the degree of urbanisation, had a strong positive effect on pollinator diversity and community composition. The same trend was observed for nesting guilds at both the community and individual guild level. This study supports the development of several costeffective and achievable conservation initiatives, such as adopting no-mow periods during austral spring and developing small-scale bee-friendly floral-rich patches, which can be undertaken by existing municipal structures and private landowners alike. Urban spaces in Cape Town have the potential to support important pollinator diversity, but more research is needed. Suggested future studies include investigating the ways pollinator diversity and community composition is influenced by 1) individual floral species and characteristics, 2) the size, shape, and location of habitat/floral patches, and 3) the effects of urban warming.