A system dynamics modelling approach to restoration of natural capital: An economic assessment of costs and benefits of different land use options and value added products to assist in the control of invasive alien plants in the fynbos biome of the Western Cape Province, South Africa

Invasive alien plants (IAPs) are major the major causes of environmental degradation in the Western Cape Province, South Africa. IAPs clearing activities have been implemented and funded largely by the state through the Working for Water Programme under the auspices of the Department of Environmental Affairs� Natural Resource Management directorates (DEA: NRM), to counteract these negative impacts. Using a system dynamics modelling approach, this study estimates the costs and benefits of clearing IAPs, using the cleared biomass to make VAPs and restoring the cleared land to various agricultural land use options under five broad management scenarios using a system dynamics modelling approach. The simulation results show positive cumulative net present values (NPV) when a private sector co-finance of between 20% and 100% from the private sector is included to clear IAPs whilst at the same time restoring the cleared land to productive agricultural land uses and making VAPs from the cleared IAPs biomass. However if the clearing of IAPs is conducted by the state alone (with no private sector co-finance) from 2008 whilst omitting the restoration of cleared land to productive agricultural land use options and the use of IAPs biomass to make VAPs , the cumulative NPV is negative.