Restore/create brackish/saline swamps in areas that will be climatically suitable in the future
Overall effectiveness category Unknown effectiveness (limited evidence)
Number of studies: 1
Background information and definitions
It may be wise to prioritize restoration or creation of swamps in areas that will remain – or become more – climatically suitable in the future, rather than areas that are destined to become unsuitable. These areas will provide space for existing vegetation to move into as their current sites become to dry, wet, warm or cold (Oliver et al. 2012).
Oliver T.H., Smithers R.J., Bailey S., Walmsley C.A. & Watts K. (2012) A decision framework for considering climate change adaptation in biodiversity conservation planning. Journal of Applied Ecology, 49, 1247–1255.
Supporting evidence from individual studies
A before-and-after study in 1969–2011 in an estuary in South Africa (Hoppe-Speer et al. 2015) reported that over 42 years after planting mangrove trees just outside their current range, the area of mangrove vegetation increased. Before planting, there were no mangroves present in the estuary. In the year after planting (1970), mangrove forests could not be identified on aerial photographs. Forty-two years after planting (2011), mangrove forests had established and covered 1.6 ha. Although mangroves encroached into and replaced existing salt marshes, the area of salt marsh in the estuary actually increased slightly over time (1970: 2.9 ha; 2011: 3.1 ha). Salt marshes developed on newly deposited sediment. Methods: In 1969, twenty-five grey mangrove Avicennia marina trees (age unclear) were planted into salt marsh in the Nahoon Estuary. This site is 60 km south of naturally occurring mangrove forests in South Africa. “A few” mangrove trees of other species were planted “a few” years later. The area of mangrove forest and salt marsh in the estuary was determined from aerial photographs (taken 1970–2004), satellite images (taken 2004–2010) and field surveys (2011).Study and other actions tested