A dynamic modelling tool to anticipate the effectiveness of invasive plant control and restoration recovery trajectories in South African Fynbos

Background: The South African National Environmental Management: Biodiversity Act (No. 10 of 2004) (NEM:BA) requires all Organs of State at all spheres of government to develop invasive species monitoring, control and eradication plans. Municipalities across South Africa are required to comply with the Alien and Invasive Species Regulations under NEM:BA but are faced with myriad challenges, making compliance difficult. Objective: This paper unpacks some of the challenges municipalities face and provides guidance on how to overcome these in order to achieve NEM:BA compliance. Through a strategic, municipal-wide approach involving different landowners, compliance can be achieved and many of the associated challenges can be overcome. For example, lack of awareness and capacity within municipal structures can be addressed through various platforms that have proven successful in some areas. Conclusions: Using the City of Cape Town as a case study, we highlight some of the notable successes in overcoming some of these challenges. For example, the City’s Invasive Species Strategy has resulted in municipal buy-in, departmental collaboration and a city-wide invasive plant tender, allowing for streamlined invasive plant control across the city. We present a framework as a first step towards measuring compliance and how the national status report can measure the level of compliance by Organs of State.

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A multi-criterion approach for prioritizing areas in urban ecosystems for active restoration following invasive plant control

Environmental Management ◽

10.1007/s00267-018-1103-9 ◽

2018 ◽

Vol 62 (6) ◽

pp. 1150-1167 ◽

Cited By ~ 5

Author(s):

Elana Mostert ◽

Mirijam Gaertner ◽

Patricia M. Holmes ◽

Patrick J. O’Farrell ◽

David M. Richardson

Keyword(s):

Invasive Plant ◽

Urban Ecosystems ◽

Active Restoration ◽

Criterion Approach ◽

Plant Control

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Autotomy in plants: organ sacrifice in Oxalis leaves

Journal of The Royal Society Interface ◽

10.1098/rsif.2018.0737 ◽

2019 ◽

Vol 16 (151) ◽

pp. 20180737 ◽

Cited By ~ 1

Author(s):

Ilana Shtein ◽

Alex Koyfman ◽

Amram Eshel ◽

Benny Bar-On

Keyword(s):

South African ◽

Invasive Plant ◽

Body Part ◽

Mechanical Analysis ◽

Small Cells ◽

African Origin ◽

Whole Plant ◽

Defence Strategy ◽

Far Field Stress ◽

The Sacrifice

Autotomy is a self-defence strategy of sacrificing a body part for survival. This phenomenon is widespread in the animal kingdom (e.g. gecko's tail) but was never reported in plants. In this study, we characterize the autotomy mechanism in the leaves of an invasive plant of South African origin, Oxalis pes-caprae. When the leaves and flowers of this plant are pulled, they break easily at their base, leaving the rest of the plant intact. Microscopic observations of the leaves reveal an area of small cells and a marked notch at this designated breaking point. Mechanical analysis showed that the strength statistics of the petioles follow Weibull's function. A comparison of the function parameters confirmed that strength of the tissue at that point is significantly smaller than at other points along the petiole, while the toughness of the tissue at the notch and at mid-petiole are approximately the same. We conclude that leaf fracture in Oxalis is facilitated by an amplification of the far-field stress in the vicinity of local, but abrupt, geometrical modification in the form of a notch. This presents an autotomy-like defence mechanism which involves the sacrifice of vital organs in order to prevent the uprooting of the whole plant.

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Effectiveness of Calluna-heathland restoration methods after invasive plant control

Ecological Engineering ◽

10.1016/j.ecoleng.2013.01.038 ◽

2013 ◽

Vol 54 ◽

pp. 218-226 ◽

Cited By ~ 9

Author(s):

Josu G. Alday ◽

Emma S. Cox ◽

Robin J. Pakeman ◽

Mike P.K. Harris ◽

Mike G. Le Duc ◽

...

Keyword(s):

Invasive Plant ◽

Plant Control

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Invasive Plant Control by Livestock: From Targeted Eradication to Ecosystem Restoration

Ecological Restoration ◽

10.3368/er.29.3.209 ◽

2011 ◽

Vol 29 (3) ◽

pp. 209-211 ◽

Cited By ~ 3

Author(s):

G. S. Kleppel ◽

C. B. Girard ◽

S. Caggiano ◽

E. LaBarge

Keyword(s):

Invasive Plant ◽

Ecosystem Restoration ◽

Plant Control

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Impact of invasive plant control on soil loss: a case study on Robinson Crusoe Island

Restoration Ecology ◽

10.1111/rec.12700 ◽

2018 ◽

Vol 26 (6) ◽

pp. 1165-1169 ◽

Cited By ~ 1

Author(s):

Jessica Castillo ◽

Cecilia Smith-Ramírez

Keyword(s):

Soil Loss ◽

Invasive Plant ◽

Robinson Crusoe ◽

Plant Control

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Forty years later: monitoring and status of the endangered Coachella Valley fringe-toed lizard

California Fish and Wildlife Journal ◽

10.51492/cfwj.cesasi.14 ◽

2021 ◽

pp. 243-257

Author(s):

Cameron W. Barrows ◽

Scott A. Heacox

Keyword(s):

Environmental Variables ◽

Sand Dune ◽

Invasive Plant ◽

Private Property ◽

Ecosystem Processes ◽

Coachella Valley ◽

Management Actions ◽

Habitat Islands ◽

Uma Inornata ◽

Plant Control

The Coachella Valley fringe-toed lizard, Uma inornata, was listed as endangered under the California Endangered Species Act in 1980. By that time, the lizard’s habitat was already reduced by 90%, fragmented into isolated habitat islands on private property among hundreds of landowners. Ecosystem processes that are essential for delivering sand and maintaining the lizard’s sand dune habitat were already compromised. As challenging as it was to protect its habitat under these conditions, populations of this lizard still occur across much of the area where it was found forty years ago. Annual monitoring was designed to assess the ongoing viability of these populations by quantifying the effects of potential threats and stressors and focusing adaptive management actions where they are most needed. Here we demonstrate how hypothesis-based monitoring identified specific locations where invasive plant control and sand corridor management were needed to maintain the lizard’s populations. By monitoring lizard densities within the context of environmental variables that either drive or inhibit population growth, this monitoring approach informs if, when, and where management actions are needed.

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Use of a rapid roadside survey to detect potentially invasive plant species along the Garden Route, South Africa

Koedoe ◽

10.4102/koedoe.v61i1.1515 ◽

2019 ◽

Vol 61 (1) ◽

Cited By ~ 4

Author(s):

Johan A. Baard ◽

Tineke Kraaij

Keyword(s):

South Africa ◽

South African ◽

National Park ◽

Invasive Plant ◽

Alien Plants ◽

Plant Distribution ◽

Plant Management ◽

Alien Plant ◽

Invasive Alien Plant ◽

Roadside Survey

Early detection of emerging or sleeper weeds and monitoring of alien plant invasions forms the foundation of effective invasive alien plant management. Using a rapid roadside survey technique, we aimed to (1) establish a baseline of alien plant distribution and abundance along roads in the Garden Route, South Africa, and (2) identify priority species (particularly sleeper weeds) and priority areas to inform appropriate management action. We surveyed along 530 km of roads and recorded 109 alien and/or extralimital species across 1942 point locations. Of these, 35 species were considered to be sleeper weeds on account of displaying estimated dispersal distances distinctive of invasive plants and not being listed by the South African Plant Invaders Atlas (SAPIA) or regulated by South African legislation. Roads along natural forest and fynbos vegetation (often within the Garden Route National Park) displayed lower incidences of alien plants than those associated with degraded or transformed land, with roads along farmland associated with the highest incidences of alien plants. Roads in the Southern Cape region had more species and higher densities of alien plants than roads in the Tsitsikamma region, and a few species were exclusive to either.Conservation implications: Our inventory contributed significant new records and range extensions to SAPIA, while the identified sleeper weeds offered suggestions for species that may be considered for regulation under the National Environmental Management: Biodiversity Act of South Africa. We furthermore provided information to facilitate (1) timely management of emerging invasive alien plants, (2) prioritisation of species and areas for management action, and (3) future monitoring of alien plants in the Garden Route National Park and surrounds.

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Estimating the Value of Invasive Aquatic Plant Control: A Bioeconomic Analysis of 13 Public Lakes in Florida

Journal of Agricultural and Applied Economics ◽

10.1017/s1074070800028972 ◽

2007 ◽

Vol 39 (s1) ◽

pp. 97-109 ◽

Cited By ~ 14

Author(s):

Damian C. Adams ◽

Donna J. Lee

Keyword(s):

Steady State ◽

Water Hyacinth ◽

Aquatic Plant ◽

Invasive Plant ◽

Water Lettuce ◽

Net Benefit ◽

Invasive Aquatic Plant ◽

Invasive Aquatic Plants ◽

One Year ◽

Plant Control

We present a bioeconomic model of three invasive aquatic plants (hydrilla, water hyacinth, and water lettuce) in 13 large Florida lakes, and simulate one-year and steady-state impacts of three control scenarios. We estimate that the steady-state annual net benefit of invasive plant control is $59.95 million. A one-year increase in control yields steady-state gains of $6.55 million per year, and a one-year lapse causes steady-state annual losses of $18.71 million. This model shows that increased control of hydrilla, water hyacinth, and water lettuce is optimal.

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