but include value-added industries related to alien biomass removal, such as firewood, charcoal and biomass to electricity industries (Stafford and Blignaut 2017).
Managing and valuing ecosystem services remains a challenge in South Africa and
globally, with native ecosystems typically undervalued, and is not limited to the field
of restoration ecology. The accuracy of measuring restoration success is complicated
because policy is still dictated by narrow, mainstream economic ideas (Costanza
et al. 2017). Furthermore, information, databases and models related to ecosystem
services in South Africa and elsewhere could be developed further, integrated and
made available to stakeholders to ensure ecosystem services are optimised (Turner
et al. 2016). One well-studied example is the negative impact of invasive alien trees
on water supply and the benefits of restoring water catchments (Marais and
Wannenburgh 2008).
Mountain fynbos ecosystems are important for the delivery of clean water to
downstream agricultural and urban areas and for wild flower harvesting and ecotourism, among other services. Invasion by alien trees has severely disrupted these
services (Holmes et al. 2007). Recovery potential is initially high in these ecosystems, owing to persistent soil-stored native seed banks, but this declines with the
duration and density of invasion (Galloway et al. 2017; Holmes and Cowling 1997).
For example, the benefit-cost ratio for total alien clearance (initial plus follow-ups)
was 8:1 for medium-dense alien stands compared to 3:1 (at 4% discount rate) for
long-term, closed alien stands (Holmes et al. 2007). Therefore, in an attempt to guide
decisions on when restoration activities may be feasible, Crookes et al. (2013)
coupled ecological restoration with system dynamics and portfolio mapping. They
showed how restoration costs and derived benefits varied across sites, but that those
projects in South Africa with the highest expectations of success and high payoffs
were those associated with protection of water resources—justifying the focus on
alien-clearing related restoration efforts in catchment areas.
Turpie et al. (2008) suggested that these valuable ecosystem services, such as
water, should act as ‘umbrella services’ and that doing so would enhance broader
conservation goals. In South Africa, payments for ecosystem services only started
with the establishment of the Working for Water programme in 1995.
From an ecosystem services viewpoint, an increased investment in restoration
activities often is warranted (Anderson et al. 2017). However, the effectiveness of
these investments will differ depending on their costs and aims. For example, Currie
et al. (2009) determined the cost-effectiveness of restoration by using the costs of
invasive alien plant clearing, erosion control and revegetation as the input costs and
water and tourism as the benefits. Importantly, they compared three different restoration options (comprehensive, moderate, basic) and three economic scenarios
(optimistic, realistic, pessimistic). They found that comprehensive restoration was
not worth the input costs, basic restoration was always economically viable, whilst
for moderate restoration it depended on the economic scenario selected. Naturally,
these results are highly dependent on the invasive alien species, the ecosystem type
and potential benefits, highlighting the importance of conducting such studies in a
variety of ecosystems. Gaertner et al. (2012c) showed that for flower harvesting,
active fynbos restoration is financially feasible for flower harvesters compared to
23 Biological Invasions and Ecological Restoration in South Africa
677
Managing and valuing ecosystem services remains a challenge in South Africa and
globally, with native ecosystems typically undervalued, and is not limited to the field
of restoration ecology. The accuracy of measuring restoration success is complicated
because policy is still dictated by narrow, mainstream economic ideas (Costanza
et al. 2017). Furthermore, information, databases and models related to ecosystem
services in South Africa and elsewhere could be developed further, integrated and
made available to stakeholders to ensure ecosystem services are optimised (Turner
et al. 2016). One well-studied example is the negative impact of invasive alien trees
on water supply and the benefits of restoring water catchments (Marais and
Wannenburgh 2008).
Mountain fynbos ecosystems are important for the delivery of clean water to
downstream agricultural and urban areas and for wild flower harvesting and ecotourism, among other services. Invasion by alien trees has severely disrupted these
services (Holmes et al. 2007). Recovery potential is initially high in these ecosystems, owing to persistent soil-stored native seed banks, but this declines with the
duration and density of invasion (Galloway et al. 2017; Holmes and Cowling 1997).
For example, the benefit-cost ratio for total alien clearance (initial plus follow-ups)
was 8:1 for medium-dense alien stands compared to 3:1 (at 4% discount rate) for
long-term, closed alien stands (Holmes et al. 2007). Therefore, in an attempt to guide
decisions on when restoration activities may be feasible, Crookes et al. (2013)
coupled ecological restoration with system dynamics and portfolio mapping. They
showed how restoration costs and derived benefits varied across sites, but that those
projects in South Africa with the highest expectations of success and high payoffs
were those associated with protection of water resources—justifying the focus on
alien-clearing related restoration efforts in catchment areas.
Turpie et al. (2008) suggested that these valuable ecosystem services, such as
water, should act as ‘umbrella services’ and that doing so would enhance broader
conservation goals. In South Africa, payments for ecosystem services only started
with the establishment of the Working for Water programme in 1995.
From an ecosystem services viewpoint, an increased investment in restoration
activities often is warranted (Anderson et al. 2017). However, the effectiveness of
these investments will differ depending on their costs and aims. For example, Currie
et al. (2009) determined the cost-effectiveness of restoration by using the costs of
invasive alien plant clearing, erosion control and revegetation as the input costs and
water and tourism as the benefits. Importantly, they compared three different restoration options (comprehensive, moderate, basic) and three economic scenarios
(optimistic, realistic, pessimistic). They found that comprehensive restoration was
not worth the input costs, basic restoration was always economically viable, whilst
for moderate restoration it depended on the economic scenario selected. Naturally,
these results are highly dependent on the invasive alien species, the ecosystem type
and potential benefits, highlighting the importance of conducting such studies in a
variety of ecosystems. Gaertner et al. (2012c) showed that for flower harvesting,
active fynbos restoration is financially feasible for flower harvesters compared to
23 Biological Invasions and Ecological Restoration in South Africa
677