Refugial potential – Continental 9-second analyses

Due to the considerable computation time required to run each of the continental refugial potential analyses (section 4.3.8), the full analytical process was completed for only four of the 15 biological groups: Order Proteales (banksias, grevilleas etc.), Order Fabales (peas, including acacias), reptiles and amphibians. However, all required inputs for the remaining biological groups have been prepared, including all projected environmental variables, biotically scaled at 250 m resolution, using the fitted GDMs for these groups. Potential therefore exists to undertake the final stage of processing; that

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is, the refugial analysis itself, for each of these groups in the future, if resourcing of required staff time can be secured beyond this project.

Figure 38: Continental analyses of refugial potential (based on compositional-turnover modelling).

We first assessed the effect that varying assumed dispersal capacity has on the identification of refugial potential for a single combination of biological group, Order Proteales, and climate scenario, RCP8.5 using the GFDL GCM. While the results exhibited some sensitivity to the choice of 1 km, 10 km or 50 km dispersal capacity, overall patterns of refugial potential generated by these three analyses were

reasonably consistent, at least at continental scale (Figure 36). The remaining continental analysis runs completed for this report were therefore performed using a single dispersal value, that is, the intermediate distance of 10 km.

Climate change refugia for terrestrial biodiversity 65 Figure 39: Refugial potential based on compositional-turnover modelling of the Order Proteales (banksias, grevilleas etc.), assuming three different dispersal capacities. GCM: GFDL. RCP: 8.5 (to 2085).

Results obtained from analyses of all possible combinations of the four selected biological groups, two GCMs (GFDL vs MIROC) and two RCPs (6.0 and 8.5) exhibited considerable variation both between climate scenarios within a given biological groups, and between groups within a given scenario. Examples of this variation are presented in Figure 37 (four climate scenarios for a single group, the Proteales) and Figure 38 (four biological groups for a single climate scenario, GCM: GFDL , RCP: 8.5).

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Figure 40: Refugial potential based on compositional-turnover modelling of the Order Proteales (banksias, grevilleas etc.), for four climate scenarios (to 2085).

Figure 41: Refugial potential based on compositional-turnover modelling of four different biological groups: Order Proteales (banksias, grevilleas etc.), Order Fabales (peas, including acacias), reptiles, and amphibians. GCM: GFDL. RCP:

8.5 (to 2085).

Climate change refugia for terrestrial biodiversity 67 Figure 42: Refugial potential averaged across Proteales, Fabales, reptiles, and amphibians, and four climate scenarios (to 2085). The red rectangles indicate areas depicted in greater detail.

To provide an indication of overall refugial potential across biological groups and across climate scenarios, the results of all 16 combinations of groups and scenarios were averaged, yielding the continental map presented in Figure 39.

Selected portions of this map are enlarged, and presented in greater detail, in Figure 40 to Figure 44, thereby providing a clearer indication of the 250 m spatial resolution of the analysis, and the effects of topography on refugial potential at finer scales. These enlarged maps also depict the location of protected areas within the National Reserve System (NRS), and mask out areas of land from which native vegetation has been ostensibly removed (based on mapping from the National Vegetation Information System, NVIS).

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Figure 43: Enlarged portion (Kimberley region) of map presented in Figure 39, depicting refugial potential averaged across Proteales, Fabales, reptiles, and amphibians, and four climate scenarios (to 2085). Protected areas included as hatched overlay.

Figure 44: Enlarged portion (Central Ranges) of map presented in Figure 39, depicting refugial potential averaged across Proteales, Fabales, reptiles, and amphibians, and four climate scenarios (to 2085). Protected areas included as hatched overlay.

Climate change refugia for terrestrial biodiversity 69 Figure 45: Enlarged portion (Wet Tropics) of map presented in Figure 39,

depicting refugial potential averaged across Proteales, Fabales, reptiles, and amphibians, and four climate scenarios (to 2085). Protected areas included as hatched overlay. Cleared land depicted in grey.

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Figure 46: Enlarged portion (Sydney Basin) of map presented in Figure 39, depicting refugial potential averaged across Proteales, Fabales, reptiles, and amphibians, and four climate scenarios (to 2085). Protected areas included as hatched overlay. Cleared land depicted in grey.

Climate change refugia for terrestrial biodiversity 71 Figure 47: Enlarged portion (Tasmania) of map presented in Figure 39, depicting refugial potential averaged across Proteales, Fabales, reptiles, and amphibians, and four climate scenarios (to 2085). Protected areas included as hatched overlay. Cleared land depicted in grey.

An overall indication of the current level of protection of areas of high refugial potential afforded by the National Reserve System (NRS) is provided in Figure 45 and Figure 46. These maps colour areas of relatively high refugial potential, extracted from Figure 39, according to whether these lie inside or outside current boundaries of NRS.

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Figure 48: Inclusion of areas of highest refugial potential (based on the averaged results for Proteales, Fabales, reptiles and amphibians) within the National Reserve System.

Figure 49: Inclusion of areas of highest refugial potential (based on the averaged results for Proteales, Fabales, reptiles and amphibians) within the National Reserve System, detail for the ‘Top End’.

Climate change refugia for terrestrial biodiversity 73 4.4.2.1 Refugial potential – NSW 3-second analyses

Results from the trial application of the refugial-potential analysis to higher quality biological data (floristic survey plot data), and 100 m grid-resolution environmental layers, for NSW are illustrated in Figure 47.

Figure 50: Refugial potential in NSW based on compositional-turnover modelling of vascular plants at 100 m grid resolution. GCM: CSIRO Mk 3.5. Emission

scenario: A1B (to 2070). Protected areas depicted as hatched overlay. Cleared land depicted in grey.