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Novoa A, Shackleton R, Canavan S, Cybèle C, Davies SJ, Dehnen-Schmutz K, Fried J, Gaertner M, Geerts S, Griffiths CL, Kaplan H, Kumschick S, Le Maitre DC, Measey GJ, Nunes AL, Richardson DM, Robinson TB, Touza J, Wilson JRU. A framework for engaging stakeholders on the management of alien species. J Environ Manage 2018; 205:286-297. [PMID: 29024897 DOI: 10.1016/j.jenvman.2017.09.059] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Revised: 09/20/2017] [Accepted: 09/21/2017] [Indexed: 05/28/2023]
Abstract
Alien species can have major ecological and socioeconomic impacts in their novel ranges and so effective management actions are needed. However, management can be contentious and create conflicts, especially when stakeholders who benefit from alien species are different from those who incur costs. Such conflicts of interests mean that management strategies can often not be implemented. There is, therefore, increasing interest in engaging stakeholders affected by alien species or by their management. Through a facilitated workshop and consultation process including academics and managers working on a variety of organisms and in different areas (urban and rural) and ecosystems (terrestrial and aquatic), we developed a framework for engaging stakeholders in the management of alien species. The proposed framework for stakeholder engagement consists of 12 steps: (1) identify stakeholders; (2) select key stakeholders for engagement; (3) explore key stakeholders' perceptions and develop initial aims for management; (4) engage key stakeholders in the development of a draft management strategy; (5) re-explore key stakeholders' perceptions and revise the aims of the strategy; (6) co-design general aims, management objectives and time frames with key stakeholders; (7) co-design a management strategy; (8) facilitate stakeholders' ownership of the strategy and adapt as required; and (9) implement the strategy and monitor management actions to evaluate the need for additional or future actions. In case additional management is needed after these actions take place, some extra steps should be taken: (10) identify any new stakeholders, benefits, and costs; (11) monitor engagement; and (12) revise management strategy. Overall, we believe that our framework provides an effective approach to minimize the impact of conflicts created by alien species management.
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Affiliation(s)
- Ana Novoa
- Centre for Invasion Biology, Department of Botany and Zoology, Stellenbosch University, Matieland, South Africa; South African National Biodiversity Institute, Kirstenbosch Research Centre, Claremont, South Africa; Institute of Botany, Department of Invasion Ecology, The Czech Academy of Sciences, CZ-252 43, Průhonice, Czech Republic.
| | - Ross Shackleton
- Centre for Invasion Biology, Department of Botany and Zoology, Stellenbosch University, Matieland, South Africa
| | - Susan Canavan
- Centre for Invasion Biology, Department of Botany and Zoology, Stellenbosch University, Matieland, South Africa; South African National Biodiversity Institute, Kirstenbosch Research Centre, Claremont, South Africa
| | - Cathleen Cybèle
- CIRAD, UMR PVBMT, Saint-Pierre, La Réunion, France; Université de la Réunion, UMR PVBMT, F-97410, Saint-Pierre, La Réunion, France
| | - Sarah J Davies
- Centre for Invasion Biology, Department of Botany and Zoology, Stellenbosch University, Matieland, South Africa
| | - Katharina Dehnen-Schmutz
- Centre for Agroecology, Water and Resilience, Coventry University, Ryton Gardens, Wolston Lane, Coventry, CV8 3LG, UK
| | - Jana Fried
- Centre for Agroecology, Water and Resilience, Coventry University, Ryton Gardens, Wolston Lane, Coventry, CV8 3LG, UK
| | - Mirijam Gaertner
- Centre for Invasion Biology, Department of Botany and Zoology, Stellenbosch University, Matieland, South Africa; Nürtingen-Geislingen University of Applied Sciences (HFWU), Nürtingen, Germany
| | - Sjirk Geerts
- Department Conservation and Marine Science, Cape Peninsula University of Technology, P.O. Box 652, Cape Town, 8000, South Africa
| | - Charles L Griffiths
- Marine Research (MA-RE) Institute, University of Cape Town, Private Bag X3, Rondebosch, 7701, South Africa; Department of Biological Sciences, University of Cape Town, Private Bag X3, Rondebosch, 7701, South Africa
| | - Haylee Kaplan
- South African National Biodiversity Institute, Kirstenbosch Research Centre, Claremont, South Africa
| | - Sabrina Kumschick
- Centre for Invasion Biology, Department of Botany and Zoology, Stellenbosch University, Matieland, South Africa; South African National Biodiversity Institute, Kirstenbosch Research Centre, Claremont, South Africa
| | - David C Le Maitre
- Council for Industrial and Scientific Research, P.O. Box 320, Stellenbosch, 7599, South Africa
| | - G John Measey
- Centre for Invasion Biology, Department of Botany and Zoology, Stellenbosch University, Matieland, South Africa
| | - Ana L Nunes
- Centre for Invasion Biology, Department of Botany and Zoology, Stellenbosch University, Matieland, South Africa; South African National Biodiversity Institute, Kirstenbosch Research Centre, Claremont, South Africa; South African Institute for Aquatic Biodiversity, Grahamstown, South Africa
| | - David M Richardson
- Centre for Invasion Biology, Department of Botany and Zoology, Stellenbosch University, Matieland, South Africa
| | - Tamara B Robinson
- Centre for Invasion Biology, Department of Botany and Zoology, Stellenbosch University, Matieland, South Africa
| | - Julia Touza
- Environment Department, Wentworth Way, University of York, Heslington, York, YO10 5NG, UK
| | - John R U Wilson
- Centre for Invasion Biology, Department of Botany and Zoology, Stellenbosch University, Matieland, South Africa; South African National Biodiversity Institute, Kirstenbosch Research Centre, Claremont, South Africa
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Fill JM, Forsyth GG, Kritzinger-Klopper S, Le Maitre DC, van Wilgen BW. An assessment of the effectiveness of a long-term ecosystem restoration project in a fynbos shrubland catchment in South Africa. J Environ Manage 2017; 185:1-10. [PMID: 27815003 DOI: 10.1016/j.jenvman.2016.10.053] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2016] [Revised: 09/08/2016] [Accepted: 10/24/2016] [Indexed: 06/06/2023]
Abstract
The long-term effectiveness of ecological restoration projects is seldom reported in the scientific literature. This paper reports on the outcomes of ecosystem restoration following the clearing of alien Pinus plantations and associated alien plant invasions over 13 years from an 8000 ha mountain catchment in the Western Cape Province, South Africa. We examined the goals, methods and costs of management, and the ecological outcomes in terms of reduced alien plant cover and native vegetation recovery. While the goals were not explicitly formulated at the outset, they were implicitly focussed on the conservation of water resources, the restoration of biodiversity, and the provision of employment. Initially, most (>90% of the area) was occupied by Pinus and Acacia invasions, mostly at low densities. The cost of control (initial clearing and up to 16 follow-up visits to remove emergent seedlings) amounted to almost ZAR 50 million (14 ZAR ∼ 1US$). Although the cover of alien plants was greatly reduced, over 1000 ha still support dense or medium invasions (>25% cover), and the area occupied by scattered Pinus plants increased by over 3000 ha to >5700 ha. A reliance on passive restoration had not yet resulted in full recovery of the natural vegetation. The mean number of species, and total projected canopy cover on 50 m2 plots was lower in cleared than in comparable reference sites with pristine vegetation (21 vs 32 species/plot, and 94 vs 168% cover respectively). While the project is ongoing, we conclude that the entire area could revert to a more densely-invaded state in the event of a reduction of funding. Several changes to the management approach (including the integrated use of fire, a greater use of power tools, and active re-seeding of cleared areas with indigenous shrubs) would substantially increase the future effectiveness of the project and the sustainability of its outcomes.
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Affiliation(s)
- Jennifer M Fill
- Centre for Invasion Biology, Department of Botany and Zoology, Stellenbosch University, Private Bag X1, Matieland, 7602, South Africa.
| | - Greg G Forsyth
- Centre for Invasion Biology, Natural Resources and the Environment, Council for Scientific and Industrial Research, P.O. Box 320, Stellenbosch, 7600, South Africa
| | - Suzaan Kritzinger-Klopper
- Centre for Invasion Biology, Department of Botany and Zoology, Stellenbosch University, Private Bag X1, Matieland, 7602, South Africa
| | - David C Le Maitre
- Centre for Invasion Biology, Natural Resources and the Environment, Council for Scientific and Industrial Research, P.O. Box 320, Stellenbosch, 7600, South Africa
| | - Brian W van Wilgen
- Centre for Invasion Biology, Department of Botany and Zoology, Stellenbosch University, Private Bag X1, Matieland, 7602, South Africa
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Shackleton RT, Le Maitre DC, Richardson DM. Stakeholder perceptions and practices regarding Prosopis (mesquite) invasions and management in South Africa. Ambio 2015; 44:569-81. [PMID: 25547521 PMCID: PMC4552717 DOI: 10.1007/s13280-014-0597-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Revised: 11/10/2014] [Accepted: 11/24/2014] [Indexed: 05/04/2023]
Abstract
Invasive alien trees impact the environment and human livelihoods. The human dimensions of such invasions are less well understood than the ecological aspects, and this is hindering the development of effective management strategies. Semi-structured interviews were undertaken to investigate the knowledge and perceptions of Prosopis between different stakeholder groups. Chi-squared tests, Welch ANOVAs, and Principle Component Analyses were run. Factors such as land tenure and proximity to invasions were especially important for explaining differences in perceptions and practices relating to Prosopis among different stakeholder groups. Most respondents were aware of Prosopis and considered it to be invasive (i.e., spreading). Costs associated with Prosopis were perceived to exceed benefits, and most stakeholders wanted to see a reduction in the abundance of Prosopis stands. The mean total cost for the management of Prosopis was US$ 1914 year(-1) per farm, where costs ranged from under US$ 10 to over UD$ 500 per ha based on invasion densities and objectives for control. The findings highlight the need for more effective management interventions.
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Affiliation(s)
- Ross T Shackleton
- Centre for Invasion Biology, Department of Botany and Zoology, Stellenbosch University, Private Bag X1, Matieland, 7602, South Africa,
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Rebelo AJ, Le Maitre DC, Esler KJ, Cowling RM. Hydrological responses of a valley-bottom wetland to land-use/land-cover change in a South African catchment: making a case for wetland restoration. Restor Ecol 2015. [DOI: 10.1111/rec.12251] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Alanna J. Rebelo
- Department of Conservation Ecology and Entomology; Stellenbosch University; JS Marais Building, Victoria Street 7600 Stellenbosch South Africa
- Ecosystem Management Research Group (ECOBE), Department of Biology; University of Antwerp; Office 2.20, Building C, Universiteitsplein 1, Wilrijk 2610 Antwerp Belgium
| | - David C. Le Maitre
- Council for Scientific and Industrial Research (CSIR); PO Box 320 7600 Stellenbosch South Africa
| | - Karen J. Esler
- Department of Conservation Ecology and Entomology; Stellenbosch University; JS Marais Building, Victoria Street 7600 Stellenbosch South Africa
- Centre for Invasion Biology (C.I.B); Stellenbosch South Africa
| | - Richard M. Cowling
- Department of Botany; Nelson Mandela Metropolitan University; PO Box 7700 6031 Port Elizabeth South Africa
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Shackleton RT, Le Maitre DC, Pasiecznik NM, Richardson DM. Prosopis: a global assessment of the biogeography, benefits, impacts and management of one of the world's worst woody invasive plant taxa. AoB Plants 2014; 6:plu027. [PMID: 24899150 PMCID: PMC4086457 DOI: 10.1093/aobpla/plu027] [Citation(s) in RCA: 72] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2014] [Accepted: 05/28/2014] [Indexed: 05/21/2023]
Abstract
Invasive species cause ecological, economic and social impacts and are key drivers of global change. This is the case for the genus Prosopis (mesquite; Fabaceae) where several taxa are among the world's most damaging invasive species. Many contentious issues ('conflicts of interest') surround these taxa, and management interventions have not yet sustainably reduced the negative impacts. There is an urgent need to better understand the factors that drive invasions and shape management actions, and to compare the effectiveness of different management approaches. This paper presents a global review of Prosopis, focusing on its distribution, impacts, benefits and approaches to management. Prosopis was found to occur in a 129 countries globally and many more countries are climatically suitable. All areas with naturalized or invasive Prosopis species at present are suitable for more taxa and many Asian and Mediterranean countries with no records of Prosopis are bioclimatically suitable. Several Prosopis species have substantial impacts on biodiversity, ecosystem services, and local and regional economies in their native and even more so in their invasive ranges; others provide multiple benefits to local communities. Management efforts are underway in only a small part of the invaded range. Countries where more research has been done are more likely to implement formal management than those where little published research is available. Management strategies differ among countries; developed nations use mainly mechanical and chemical control whereas developing nations tend to apply control through utilization approaches. A range of countries are also using biological control. Key gaps in knowledge and promising options for management are highlighted.
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Affiliation(s)
- Ross T Shackleton
- Department of Botany and Zoology, Centre for Invasion Biology, Private Bag X1, Stellenbosch University, Matieland 7602, South Africa
| | - David C Le Maitre
- Department of Botany and Zoology, Centre for Invasion Biology, Private Bag X1, Stellenbosch University, Matieland 7602, South Africa Natural Resources and the Environment, CSIR, P.O. Box 320, Stellenbosch 7599, South Africa
| | | | - David M Richardson
- Department of Botany and Zoology, Centre for Invasion Biology, Private Bag X1, Stellenbosch University, Matieland 7602, South Africa
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Nel JL, Le Maitre DC, Nel DC, Reyers B, Archibald S, van Wilgen BW, Forsyth GG, Theron AK, O’Farrell PJ, Kahinda JMM, Engelbrecht FA, Kapangaziwiri E, van Niekerk L, Barwell L. Natural hazards in a changing world: a case for ecosystem-based management. PLoS One 2014; 9:e95942. [PMID: 24806527 PMCID: PMC4012988 DOI: 10.1371/journal.pone.0095942] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2013] [Accepted: 04/01/2014] [Indexed: 11/18/2022] Open
Abstract
Communities worldwide are increasingly affected by natural hazards such as floods, droughts, wildfires and storm-waves. However, the causes of these increases remain underexplored, often attributed to climate changes or changes in the patterns of human exposure. This paper aims to quantify the effect of climate change, as well as land cover change, on a suite of natural hazards. Changes to four natural hazards (floods, droughts, wildfires and storm-waves) were investigated through scenario-based models using land cover and climate change drivers as inputs. Findings showed that human-induced land cover changes are likely to increase natural hazards, in some cases quite substantially. Of the drivers explored, the uncontrolled spread of invasive alien trees was estimated to halve the monthly flows experienced during extremely dry periods, and also to double fire intensities. Changes to plantation forestry management shifted the 1∶100 year flood event to a 1∶80 year return period in the most extreme scenario. Severe 1∶100 year storm-waves were estimated to occur on an annual basis with only modest human-induced coastal hardening, predominantly from removal of coastal foredunes and infrastructure development. This study suggests that through appropriate land use management (e.g. clearing invasive alien trees, re-vegetating clear-felled forests, and restoring coastal foredunes), it would be possible to reduce the impacts of natural hazards to a large degree. It also highlights the value of intact and well-managed landscapes and their role in reducing the probabilities and impacts of extreme climate events.
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Affiliation(s)
- Jeanne L. Nel
- Natural Resources and the Environment, Council for Scientific and Industrial Research (CSIR), Stellenbosch, Western Cape, South Africa
- * E-mail:
| | - David C. Le Maitre
- Natural Resources and the Environment, Council for Scientific and Industrial Research (CSIR), Stellenbosch, Western Cape, South Africa
| | - Deon C. Nel
- World Wide Fund for Nature (WWF), Cape Town, Western Cape, South Africa
| | - Belinda Reyers
- Natural Resources and the Environment, Council for Scientific and Industrial Research (CSIR), Stellenbosch, Western Cape, South Africa
| | - Sally Archibald
- School of Animal, Plant and Environmental Sciences, University of the Witwatersrand, Johannesburg, Gauteng, South Africa
- Natural Resources and the Environment, Council for Scientific and Industrial Research (CSIR), Pretoria, Gauteng, South Africa
| | - Brian W. van Wilgen
- Natural Resources and the Environment, Council for Scientific and Industrial Research (CSIR), Stellenbosch, Western Cape, South Africa
- Centre for Invasion Biology, Department of Botany and Zoology, Stellenbosch University, Stellenbosch, Western Cape, South Africa
| | - Greg G. Forsyth
- Natural Resources and the Environment, Council for Scientific and Industrial Research (CSIR), Stellenbosch, Western Cape, South Africa
| | - Andre K. Theron
- Natural Resources and the Environment, Council for Scientific and Industrial Research (CSIR), Stellenbosch, Western Cape, South Africa
| | - Patrick J. O’Farrell
- Natural Resources and the Environment, Council for Scientific and Industrial Research (CSIR), Stellenbosch, Western Cape, South Africa
| | - Jean-Marc Mwenge Kahinda
- Natural Resources and the Environment, Council for Scientific and Industrial Research (CSIR), Pretoria, Gauteng, South Africa
| | - Francois A. Engelbrecht
- Natural Resources and the Environment, Council for Scientific and Industrial Research (CSIR), Pretoria, Gauteng, South Africa
| | - Evison Kapangaziwiri
- Natural Resources and the Environment, Council for Scientific and Industrial Research (CSIR), Pretoria, Gauteng, South Africa
| | - Lara van Niekerk
- Natural Resources and the Environment, Council for Scientific and Industrial Research (CSIR), Stellenbosch, Western Cape, South Africa
| | - Laurie Barwell
- Natural Resources and the Environment, Council for Scientific and Industrial Research (CSIR), Stellenbosch, Western Cape, South Africa
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Le Maitre DC, Kruger FJ, Forsyth GG. Interfacing ecology and policy: Developing an ecological framework and evidence base to support wildfire management in South Africa. AUSTRAL ECOL 2013. [DOI: 10.1111/aec.12100] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- David C. Le Maitre
- Natural Resources and the Environment; CSIR; P.O. Box 320 Stellenbosch 7599 South Africa
| | - Fred J. Kruger
- Department of Biological Sciences; University of Cape Town; Cape Town South Africa
| | - Greg G. Forsyth
- Natural Resources and the Environment; CSIR; P.O. Box 320 Stellenbosch 7599 South Africa
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Affiliation(s)
- Bruce L. Webber
- Commonwealth Scientific and Industrial Research Organisation (CSIRO), Ecosystem Sciences and Climate Adaptation Flagship, Wembley, WA 6913, Australia; and School of Plant Biology, The University of Western Australia, Crawley, WA 6009, Australia
| | - David C. Le Maitre
- Natural Resources and Environment, Council for Scientific and Industrial Research, Stellenbosch 7599, South Africa
| | - Darren J. Kriticos
- CSIRO Ecosystem Sciences and Sustainable Agriculture Flagship, Canberra, ACT 2601, Australia; EH Graham Centre for Agricultural Innovation, Charles Sturt University, Wagga Wagga, NSW 2678, Australia; and Cooperative Research Centre for Plant Biosecurity, Bruce, ACT 2617, Australia
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van Wilgen BW, Dyer C, Hoffmann JH, Ivey P, Le Maitre DC, Moore JL, Richardson DM, Rouget M, Wannenburgh A, Wilson JRU. National-scale strategic approaches for managing introduced plants: insights from Australian acacias in South Africa. DIVERS DISTRIB 2011. [DOI: 10.1111/j.1472-4642.2011.00785.x] [Citation(s) in RCA: 132] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Webber BL, Yates CJ, Le Maitre DC, Scott JK, Kriticos DJ, Ota N, McNeill A, Le Roux JJ, Midgley GF. Modelling horses for novel climate courses: insights from projecting potential distributions of native and alien Australian acacias with correlative and mechanistic models. DIVERS DISTRIB 2011. [DOI: 10.1111/j.1472-4642.2011.00811.x] [Citation(s) in RCA: 162] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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Le Maitre DC, Gaertner M, Marchante E, Ens EJ, Holmes PM, Pauchard A, O’Farrell PJ, Rogers AM, Blanchard R, Blignaut J, Richardson DM. Impacts of invasive Australian acacias: implications for management and restoration. DIVERS DISTRIB 2011. [DOI: 10.1111/j.1472-4642.2011.00816.x] [Citation(s) in RCA: 261] [Impact Index Per Article: 20.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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Le Maitre DC, Krug RM, Hoffmann JH, Gordon AJ, Mgidi TN. Hakea sericea: Development of a model of the impacts of biological control on population dynamics and rates of spread of an invasive species. Ecol Modell 2008. [DOI: 10.1016/j.ecolmodel.2007.11.011] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Mgidi TN, Le Maitre DC, Schonegevel L, Nel JL, Rouget M, Richardson DM. Alien plant invasions--incorporating emerging invaders in regional prioritization: a pragmatic approach for Southern Africa. J Environ Manage 2007; 84:173-87. [PMID: 17067735 DOI: 10.1016/j.jenvman.2006.05.018] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2005] [Revised: 02/21/2006] [Accepted: 05/16/2006] [Indexed: 05/12/2023]
Abstract
Plant invasions are a serious threat to natural and semi-natural ecosystems worldwide. Most management-orientated research on invasions focuses on invaders that are already widespread and often have major impacts. This paper deals with "emerging" invaders-those alien species with the potential to become important problems without timely intervention. A climate matching procedure was developed to define areas of South Africa, Lesotho and Swaziland that could be invaded by 28 plant species that had previously been classified as emerging invaders. Information on the location of populations of these species in the study area was combined with information on their distributions (as native or alien) in parts of Australia and the United States of America. These two countries had the best available distribution data for this study. They also share many invasive alien plant species with South Africa. Climatic data obtained for weather stations near points of known occurrence in these countries were used to define the climatically suitable areas for each species in the study area. Almost 80% of the remaining natural environment in southern Africa was found to be vulnerable to invasion by at least one of these species, 50% by six or more and 24% by 16 or more species. The most vulnerable areas are the highveld grasslands and the eastern escarpment. The emerging invaders with the greatest potential range included Acacia podalyriifolia and Cortaderia selloana. The globally important invaders Ulex europaeus and Lythrum salicaria had a more limited invasion potential but could still become major invaders. There was no relationship between the extent of the climatically suitable areas for the different species and an expert ranking of their invasion potential, emphasising the uncertainties inherent in making expert assessments based on very little information. The methods used in this analysis establish a protocol for future modelling exercises to assess the invasion potential of other emerging invaders.
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Affiliation(s)
- Theresa N Mgidi
- Natural Resources and Environment, CSIR, Stellenbosch, South Africa
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Rouget M, Richardson DM, Nel JL, Le Maitre DC, Egoh B, Mgidi T. Mapping the potential ranges of major plant invaders in South Africa, Lesotho and Swaziland using climatic suitability. DIVERS DISTRIB 2004. [DOI: 10.1111/j.1366-9516.2004.00118.x] [Citation(s) in RCA: 144] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
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