Designing landscapes for biodiversity under climate change: Final report
|Title||Designing landscapes for biodiversity under climate change: Final report|
|Year of Publication||2013|
|Authors||Doerr, VAJ, Williams, KJ, Drielsma, M, Doerr, ED, Davies, MJ, Love, J, Langston, A, Choy, SLow, Manion, G, E. Cawsey, M, McGinness, HM, Jovanovic, T, Crawford, D, Austin, M, Ferrier, S|
|Institution||National Climate Change Adaptation Research Facility|
|Keywords||Akaike’s Information Criterion, case study, Catchment Management Authority, CMA, Generalised Linear Modelling, lanscape design, modelling, New South Wales, NSW, resilience, Terrestrial Biodiversity, Wimmera|
Landscape design – the particular placement of areas devoted to restoration of native vegetation at landscape scales – is a primary approach to climate adaptation for biodiversity management. It may facilitate the maintenance of larger populations as well as shifts in species distributions, both of which should help native species adjust to changing climates. However, it is unclear exactly how to design landscapes to best achieve these goals, particularly because a range of possible changes in land uses and shifts in species distributions are expected under climate change and these could interact with landscape design approaches for biodiversity.
We investigated whether one or more current approaches to landscape design would be robust to future climates – would tend to improve the likelihood of persistence for native species (and decrease the likelihood of persistence for key invasive species) across a range of plausible futures. Specifically, we selected two case study landscapes in south-eastern and north-eastern New South Wales and modelled 48 future landscapes for each. Future landscapes were constructed from four storylines of land-use change based on different future climates, two global climate models applied with future climates to model future vegetation communities, and three current approaches to landscape design plus controls for both spatial planning and total amount of restoration. We then used a metapopulation capacity model to evaluate the change in each landscape’s capacity to support viable populations relative to the current landscape. We modelled four native species groups: native orchids, fauna that specialise on wet forest environments, and two groups of fauna that specialise on grassy woodland and dry forest environments. We also modelled two invasive species, red fox (Vulpes vulpes) and peppercorn tree (Schinus molle). We then analysed whether the change in metapopulation capacity across all future landscapes for all species was influenced by landscape design principles. We used Generalised Linear Models and compared 14 candidate models based on alternative hypotheses using Akaike’s Information Criterion.
We found no effect of detailed spatial placement of restoration projects on the change in metapopulation capacity of our future landscapes. Only our positive control – restoring landscapes to ~30% native vegetation cover – improved future landscapes relative to current landscapes. All current design approaches failed to fully compensate for losses in metapopulation capacity resulting from climate-related changes in land use and native vegetation communities. However, the effect of design principles differed across species. The capacity of landscapes to support wet forest specialist fauna declined regardless of landscape design, and the invasive peppercorn tree increased with landscape improvements for native species. Improvement in metapopulation capacity also depended on land-use change storyline, so spatial planning of changes in land use may provide an additional management lever that is currently underutilised. We suggest that current approaches to landscape planning may not be sufficient to serve as climate adaptation strategies for biodiversity. A variety of new approaches need to be explored even if they may be challenging to implement. Greater concentration of effort in priority corridors, with local actions to match local goals, may be the best immediate action until new solutions are developed.