10 research outputs found

    Carbon sequestration on the subtropical dunes of South Africa: a comparison between native regenerating ecosystems and exotic plantations

    Get PDF
    Rehabilitation and revegetation of mined coastal sand dunes on the east coast of South Africa makes sense. It recovers ecosystem services such as carbon sequestration. The outcome of rehabilitation, which covers a third of the mined area, is a secondary coastal dune forest similar to the forests in the region. The aim of revegetation, on the other hand, is to establish Casuarina equisetifolia J.R.Forst.&G.Forst. plantations on the remaining two thirds of the mined area, for the small-scale production of charcoal. The ratio of these two post-mining land use options has consequences for the carbon sequestration potential of the mined area. As growth rate could be a reflection of carbon sequestration rate, this study compared the growth rate of Acacia kosiensis P.P.Swartz, the species that dominates rehabilitated stands, to that of C. equisetifolia in response to rainfall. The carbon sequestration potential of the two post-mining land use options was subsequently evaluated by measuring carbon storage in wood, the herb layer, litter and soil in different-aged stands. I also compared the financial potential of the two land use options. Tree ring analysis could not be applied to the two species. No correlation between growth and rainfall could be found either. On average, A. kosiensis grew twice as fast as C. equisetifolia. Carbon storage in the wood, herb layer, litter and soil in rehabilitated stands of known age (7, 11, 17 and 21 years old) differed from the revegetated stands (8, 12, 16 and 19 years old). More carbon was stored in the revegetated stands than the rehabilitated stands. I attribute this primarily to the relatively larger wood and litter components of the former. C. equisetifolia, however, is harvested for charcoal production after about sixteen years of age, thus releasing most of the carbon stored in wood. The present ratio of rehabilitation to revegetation (1:2) is not optimal for long-term carbon sequestration. Rehabilitation costs more, but the income potential thereof, as determined in this study, is less than that of revegetation. This, however, does not reflect the true financial potential of the two land use options. The financial analysis performed in this study only considered income from the sale of timber, charcoal and carbon credits. It excluded other potential benefits of the rehabilitation of coastal dune forests. These may include the contribution to biological conservation and ecological services such as dune stabilisation and water purification. Coastal dune forests also provide habitat for a variety of organisms adapted to live in them. All these have a value. Their inclusion in a detailed cost-benefit analysis could render rehabilitation as the more financially efficient option.Dissertation (MSc (Zoology))--University of Pretoria, 2007.Zoology and Entomologyunrestricte

    Towards evidence-based ecological restoration in South Africa

    Get PDF
    Thesis (PhD)--Stellenbosch University, 2012.ENGLISH ABSTRACT: Widespread, human-induced ecosystem degradation and the associated biodiversity loss pose a direct threat to human wellbeing. While there is no substitute for healthy, self-sustaining ecosystems, ecological restoration offers an attractive, and indeed inevitable, supplement where conservation alone is not sufficient to support ecosystem integrity. Restoration is undergoing a revolution, where evidence-based (EB) practice is emerging as a new approach to increase the chances of successfully achieving restoration goals. EB practice is based on the notion that implementation decisions need to be based on the appraisal and use of evidence of effectiveness of alternative options. The point of departure of this thesis is the contention that EB practice need not be dependent only on research evidence. The work presented herein thus addresses the production and use of evidence of effectiveness in restoration practice. Using ten restoration programs in South Africa, the quality of evidence produced in practice was assessed. Three components of evidence production that were evaluated were (i) baseline condition measurement; (ii) goal setting and (iii) monitoring. Results showed poor definition of goals; a bias towards the use of socio-economic goals and indicators; more monitoring of inputs than impact; and inconsistent and short-term monitoring of biophysical indicators. Practitioners regarded the evidence base as adequate, but cited a few challenges associated with planning and resource availability as attributing factors to the gaps observed. I propose that practitioners’ perception of the current evidence base poses an additional threat to the generation of a strong evidence base. In addition to the production of evidence, access to said evidence is a vital component of EB practice. In an exploration of how evidence is made available by practitioners, it became evident in that a considerable amount of the information that was not easily accessible in documented form was known by the practitioners. This highlights the need for a shift in practice culture towards the valuing and rewarding of the dissemination of information. An assessment of EB restoration would have been incomplete without a deliberate consideration of social factors. I thus conducted a case study of an invasive alien plant clearing program, to determine what drives the use of scientific evidence in decision making. I observed that organizational structure, policies, priorities and capacity influence, and even limit, the use of scientific evidence to inform decisions. The challenges to making restoration evidence-based are diverse in nature, ranging from poor planning of restoration work, which points to limited appreciation of the need to produce a strong evidence base, to a lack of instruments and incentives to drive the generation, dissemination and use of evidence that spans both the biophysical and social aspects of restoration. These challenges are largely rooted in the conventional way of approaching restoration from individual disciplinary perspectives, thus artificially simplifying and compartmentalizing a naturally complex problem like degradation. I end by proposing transdisciplinarity, which focuses on a holistic world view and the production of knowledge that embraces complexity, as a possible vehicle to help move the practice of restoration towards being evidence-based.AFRIKAANSE OPSOMMING: Wydverspreide, mens-veroorsaakte agteruitgang van ekostelsels en die gepaardgaande verlies aan biodiversiteit hou 'n direkte bedreiging vir menslike welsyn in. Alhoewel daar geen plaasvervanger is vir 'n gesonde, selfonderhoudende ekostelsel is nie, bied ekologiese restourasie 'n aantreklike en inderdaad onvermydelik, vul waar bewaring alleen nie voldoende ekosisteem integriteit kan ondersteun nie. Restourasie ondergaan tans ‘n revolusie, waar bewys gebaseerde (BG) praktyk 'n opkomende nuwe benadering om die kanse van die suksesvolle bereiking van herstel doelwitte te verhoog. BG praktyk is gebaseer op die idee dat die uitvoering van besluite gebaseer moet word op die evaluering en die gebruik van bewyse van die effektiwiteit van alternatiewe opsies. Die punt van vertrek van hierdie proefskrif is die bewering dat BG praktyk nie noodwendig afhanklik van navorsings bewys hoef te wees nie. Die werk wat hier aangebied word spreek tot die produksie en gebruik van bewyse van effektiwiteit in die restourasie praktyk. Deur die gebruik van tien restourasie programme in Suid-Afrika is die kwaliteit van die bewyse in die praktyk geassesseer. Die drie komponente van bewyse produksie wat geĂ«valueer is sluit in (i) basislyn toestand meting, (ii) doelwitstelling en (iii) monitering. Resultate toon 'n swak definisie van doelwitte; 'n vooroordeel ten gunste van die gebruik van sosio-ekonomiese doelwitte en aanwysers; meer monitering van insette as die impak; en teenstrydige en kort-termyn monitering van biofisiese aanwysers. Beofenaars het die gebruik van bewys gebaseerde inligting as voldoende beskou, maar 'n paar uitdagings wat verband hou met die beplanning en die beskikbaarheid van bronne is aangehaal as kenmerkende faktore in die gapings wat tans waargeneem word. Ek stel voor dat beoefenaars se persepsie van die huidige bewysbasis praktyk 'n bykomende bedreiging vir die generasie van 'n sterk bewybasis praktyk inhou. Benewens die produksie van bewyse, is die toegang tot bewyse 'n belangrike komponent van die BG praktyk. In die verkenning van hoe bewyse beskikbaar gestel word deur beoefenaars, is dit duidelik dat 'n aansienlike aantal inligting wel bekend is aan beofenaars maar nie maklik toeganklik in gedokumenteerde vorm is nie. Dit beklemtoon die behoefte vir 'n verskuiwing in die praktyk kultuur tot die waardering en beloning van die verspreiding van inligting. 'n Beoordeling van die BG herstel sou onvolledig wees sonder 'n doelbewuste oorweging van sosiale faktore. Ek het dus 'n gevallestudie van 'n indringerplant verwyderings program uitgevoer om vas te stel wat die gebruik van wetenskaplike bewyse in besluitneming aandryf. Ek het opgemerk dat die organisatoriese struktuur, beleid, prioriteite en kapasiteit die gebruik van wetenskaplike bewyse kan beinvloed, en selfs beperk. Die uitdagings om herstelwerk bewys-gebaseerd te maak is uiteenlopend van aard, dit wissel van swak beplanning van herstel werk, wat dui op beperkte waardering van die behoefte om 'n sterk bewyse basis te produseer, 'n gebrek aan instrumente en aansporings vir die generasie van besyse, verspreiding en gebruik van bewyse wat strek oor beide die biofisiese en maatskaplike aspekte van die restaurasie. Hierdie uitdagings is grootliks gegrond op die konvensionele manier van restaurasie wat gebaseer is op individuele dissiplinĂȘre perspektiewe,wat lei tot die kunsmatige simplifiseering van ‘n uiteraand komplekse problem soos agteruitgang. Ek eindig af deur die gebruik van transdissiplinariteit, wat fokus op 'n holistiese wĂȘreldbeskouing en die produksie en kennis van kompleksiteit insluit voor te stel, as 'n moontlike voertuig om die skuif in praktyk van restourasie na n bewys-basis te vergemaklik

    Identifying Challenges to Building an Evidence Base for Restoration Practice

    No full text
    Global acknowledgement of ecological restoration, as an important tool to complement conservation efforts, requires an effort to increase the effectiveness of restoration interventions. Evidence-based practice is purported to promote effectiveness. A central tenet of this approach is decision making that is based on evidence, not intuition. Evidence can be generated experimentally and in practice but needs to be linked to baseline information collection, clear goals and monitoring of impact. In this paper, we report on a survey conducted to assess practitioners’ perceptions of the evidence generated in restoration practice in South Africa, as well as challenges encountered in building this evidence base. Contrary to a recent assessment of this evidence base which found weaknesses, respondents viewed it as adequate and cited few obstacles to its development. Obstacles cited were mostly associated with planning and resource availability. We suggest that the disparity between practitioners’ perceptions and observed weaknesses in the evidence base could be a challenge in advancing evidence-based restoration. We explore opportunities to overcome this disparity as well as the obstacles listed by practitioners. These opportunities involve a shift from practitioners as users of scientific knowledge and evidence, to practitioners involved in the co-production of evidence needed to increase the effectiveness of restoration interventions

    No Evidence-Based Restoration Without a Sound Evidence Base: A Reply to Guldemond et al.

    Get PDF
    Evidence-based practice is not possible without an evidence base. Guldemond et al. confuse our attempt at assessing the status of the evidence base of restoration programs in South Africa with attempting to assess whether restoration is evidence-based. While we fully agree with them that there is a need to assess whether practitioners use evidence in their decision-making, we assert that use of evidence is the last step in the evidence-based approach. It is preceded by the generation (and documentation) of evidence through baseline condition assessment, proper goal setting,sound monitoring of the impacts of the chosen intervention as well as effective dissemination of resulting evidence. To answer the question whether restoration is evidence-based would require the assessment of all stages from generation to use. We chose to start at the beginning, a logical place to start.CSI

    Ecosystem service trends in basin-scale restoration initiatives: A review

    Get PDF
    24 pĂĄginas[EN] The integration of ecosystem services in ecological restoration projects presents an opportunity for enhancing benefits to human livelihood and funding sources as well as generating public support for such initiatives. This study reviewed the global trends in integrating ecosystem services in basin-scale restoration projects through bibliographic analysis. Few studies appear to incorporate ecosystem services, possibly due to the inconsistency and absence of the use of universally accepted classifications. Our review notes an increasing trend from 2006 onward toward the inclusion and citation of this concept, although its use is still limited. In this review, the supporting service was found to be the most cited (8), followed by regulatory (3), cultural (1) and provisioning (1) services. Identifying the number of services related to a restoration action was problematic when the services were not explicitly cited. We identify opportunities for increased integration of ecosystem services in basin-scale restoration projects, suggesting a conceptual framework following from new hierarchical maps. This is based on congruence between degrading processes or threat maps (e.g., thresholds of impacts) and ecosystem service maps. The resultant map will facilitate the targeting of threatened service supply at different scales from the basin scale to the scale of the restoration site. We urge the scientific community to standardize definitions and create methodologies and software tools that facilitate the incorporation of ecosystem services in large-scale restoration plans.This work was funded by Endesa S.A. through the collaborative agreement Endesa-CSIC for scientific research. The first author wants to thank Belinda Reyers for the fruitful conversation that inspirited this work and helpfulness showed in every moment. Priceless was the help and smiles that all the Biodiversity and Ecosystem Services research group of CSIR- Stellenbosch provided. The authors want to thank three anonymous referees for their suggestions which greatly improve the manuscript. M. Trabucchi was in receipt of grant from JAE-DOC Program for Advanced Study financed by the ESF, Ref. I3P-BPD-2006.Peer reviewe

    Identifying challenges to building an evidence base for restoration practice

    Get PDF
    CITATION: Ntshotsho, P., Esler, K. J. & Reyers, B. 2015. Identifying challenges to building an evidence base for restoration practice. Sustainability, 7(12):15871–15881, doi:10.3390/su71215788.The original publication is available at http://www.mdpi.com/journal/sustainabilityGlobal acknowledgement of ecological restoration, as an important tool to complement conservation efforts, requires an effort to increase the effectiveness of restoration interventions. Evidence-based practice is purported to promote effectiveness. A central tenet of this approach is decision making that is based on evidence, not intuition. Evidence can be generated experimentally and in practice but needs to be linked to baseline information collection, clear goals and monitoring of impact. In this paper, we report on a survey conducted to assess practitioners’ perceptions of the evidence generated in restoration practice in South Africa, as well as challenges encountered in building this evidence base. Contrary to a recent assessment of this evidence base which found weaknesses, respondents viewed it as adequate and cited few obstacles to its development. Obstacles cited were mostly associated with planning and resource availability. We suggest that the disparity between practitioners’ perceptions and observed weaknesses in the evidence base could be a challenge in advancing evidence-based restoration. We explore opportunities to overcome this disparity as well as the obstacles listed by practitioners. These opportunities involve a shift from practitioners as users of scientific knowledge and evidence, to practitioners involved in the co-production of evidence needed to increase the effectiveness of restoration interventions.http://www.mdpi.com/2071-1050/7/12/15788Publisher's versio

    UN Decade on Ecosystem Restoration: key considerations for Africa

    No full text
    To support and scale up global restoration efforts, the United Nations (UN) has proclaimed 2021–2030 the “UN Decade on Ecosystem Restoration.” The Decade offers significant opportunities for and challenges to restoration, in particular for Africa, a continent that has a large need and potential for restoration. We thus argue that the Decade must be a success in and for Africa, and for this to happen, opportunities and challenges to achieving its goals must be promptly identified, and considered in the planning and implementation of restoration. Here, we outline six key areas that should be considered at a strategic level by African countries during the Decade. These are: (1) ensuring effective oversight and governance relevant to Africa; (2) translating the goals to meet the African context; (3) making the case for restoration amid multiple development demands; (4) growing an African restoration community of practice based on regional need; (5) collaborating to improve restoration outcomes; and (6) establishing an Africa-relevant evidence base for restoration. We believe that these six key areas—even though they are not all novel—are currently not addressed at a level that matches the scale of the problem on the continent. Although the specific actions to be taken under each key area are dependent on the restoration context, integrating these key areas in the planning and implementation of restoration efforts will likely lead to improved restoration outcomes during the Decade

    UN Decade on Ecosystem Restoration : key considerations for Africa

    Get PDF
    To support and scale up global restoration efforts, the United Nations (UN) has proclaimed 2021-2030 the "UN Decade on Ecosystem Restoration." The Decade offers significant opportunities for and challenges to restoration, in particular for Africa, a continent that has a large need and potential for restoration. We thus argue that the Decade must be a success in and for Africa, and for this to happen, opportunities and challenges to achieving its goals must be promptly identified, and considered in the planning and implementation of restoration. Here, we outline six key areas that should be considered at a strategic level by African countries during the Decade. These are: (1) ensuring effective oversight and governance relevant to Africa; (2) translating the goals to meet the African context; (3) making the case for restoration amid multiple development demands; (4) growing an African restoration community of practice based on regional need; (5) collaborating to improve restoration outcomes; and (6) establishing an Africa-relevant evidence base for restoration. We believe that these six key areas-even though they are not all novel-are currently not addressed at a level that matches the scale of the problem on the continent. Although the specific actions to be taken under each key area are dependent on the restoration context, integrating these key areas in the planning and implementation of restoration efforts will likely lead to improved restoration outcomes during the Decade.Peer reviewe
    corecore