Limits to climate change adaptation in floodplain wetlands: The Macquarie Marshes
Authors: K.M. Jenkins, R.T. Kingsford, B.J. Wolfenden, S. Whitten, H. Parris, C. Sives, R. Rolls, and S. Hay
The primary adaptation that will transform the Macquarie Marshes ecosystem from its current state of decline is the return of adequate environmental water to restore the short and moderate IFI floodplain. The Macquarie Marshes have been severely impacted by regulation that has reduced flooding (by 59%) and extended the inter-flood interval (IFI) to the point where the ecological character of the Ramsar site has changed. With a business as usual scenario the future state of the Macquarie Marshes sees a worsening of all ecological and social indicators by 2030 and a marked decline by 2070. By 2070 the combination of markedly increased temperatures and reduced rainfall will see the core areas of Marsh reduce further and the possible loss of all floodplain with a short IFI (1-2 years). If the restoration of the IFI floodplain can occur in the next 5-10 years, the Marshes should be buffered against the 2030 projections of increased temperature and reduced runoff. However, this technological adaptation will not succeed if changes to the social institutions (behaviours), namely: a transformation of society to increase the value it places on the natural environment of the Marshes, and a review of the water sharing plan to specify shorter durations for the IF, do not occurI. Other key adaptation strategies identified include water buy-back, environmental flows, developing an adaptive management plan, social capital, responsive institutional frameworks and preserving free-flowing rivers. This study found that landholders have developed many practices to adapt to the loss of flooding due to regulation that will enable them to adapt to climate change current projections at 2030. A major limit to adaptation is the capacity of river managers to learn from problems during drought periods and implement a reviewed water sharing plan that avoids similar losses occurring again if drought intensity and frequency increase with climate change.