Investing in natural capital and national security: a comparative review of restoration projects in South Africa.
Does restoration pay? We seek to answer this question by reviewing the benefits and costs of 37 economic values derived from five groups of actual restoration-related case studies in South Africa at various scales. The mean opportunity costs of not restoring are the following (a negative value implies an economic loss to society): (i) local level single species studies concerned with clearing invasive alien plants (mean = -$27.24/ha/yr, sd = +/-22.93; n = 5); (ii) local level multiple species studies concerned with clearing invasive alien plants (mean = -$289/ha/yr, sd = +/-550.6; n = 14); (iii) national level studies concerned with clearing invasive alien plants (mean = -$40.2/ha/yr, sd = +/-17.2; n = 3); (iv) non-clearing related restoration (mean = -$52/ha/yr, sd = +/-154.2; n = 10); and (v) agricultural land rehabilitation (mean = -$428.1/ha/yr, sd = +/-352.7; n = 5). When these annual values are capitalised (i.e. discounted into perpetuity) to reflect the temporal impact of the foregone benefits of restoration, the losses amount to between 16 and 50 times greater than the annual values. Capitalisation of these values is an important step towards an asset-based approach in the management, restoration and conservation of natural capital. It is a step towards viewing the investment in restoration not merely as an expenditure item to be minimised, but as a truly worthwhile investment in the future wellbeing of both people and the planet - an investment in the national security of the country. More work, however, is required to transfer this value onto the balance sheets of companies in order to entice the private sector to invest more as well as to convert the implicit societal benefits of restoration to explicit company-wide value enhancement opportunities.