*2.1. Design and Data Collection*

For this study, the Sunshine Coast heathlands were defined as extending from Cooloola in the north, 150 km south to Bribie Island, and west up to 30 km to Mapleton and the Glasshouse Mountains. These heathlands fall within the council areas of Gympie, Noosa, Sunshine Coast, and Moreton Bay (Figure 1). The current extent and protection status of the heathlands is shown in Supplementary Figure S1.

The Queensland regional ecosystem framework is based on bioregions (broadscale landscape patterns), land zones (based on geology, soils and landforms), and vegetation (described in terms of structure and floristics) and are locally mapped at a scale of 1:50,000 [52]. To capture the diversity across the heath and to ensure the representativeness of heath types, sampling was undertaken of the mapped nine regional ecosystem (RE) heath types [53]. The Queensland Herbarium CORVEG database contained an existing dataset of thirteen sites from five regional ecosystems [54]. This dataset was expanded so that each regional ecosystem was sampled over at least six sites, although the limited extent of RE 12.12.10 meant that only three sites were sampled (Table 1). Sites were chosen which had been unaffected by fire for at least 12 months to reduce this confounding factor. There are also areas along the coast with special significance or were sites of "conservation battles" in the past [34], and some of these "iconic" areas were included to assess their diversity. To address the stratified sampling for other aspects of this project, a further 67 sites were sampled from across the Sunshine Coast study area, resulting in data for a total of 80 sites over nine regional ecosystems.

Site were selected using ArcGis 10.5: [55]: shape files of the Regional Ecosystem mapping of remnant vegetation for south-east Queensland [56] were overlaid with the Protected Area Status [57] to enable selection of sites within the Protected Area Estate. As site data were being added to the CORVEG database, collection methods were consistent with the Queensland Herbarium CORVEG techniques with a standard proforma and plot size of 1000 m<sup>2</sup> [58]. Data collection occurred during late winter, spring, and early summer, from July 2016 to December 2018. At each site, GPS bearings (10 m accuracy) were taken, and a complete native species list was recorded. The comprehensiveness of species lists was maximised by visiting each site twice, with at least one site visit aimed to be during the spring flowering peak [59]. Orchids were noted but not included in species lists, as their cryptic nature meant they were unable to be recorded consistently; likewise, ferns and bryophytes were noted but their inclusion was beyond the scope of this study. Species were identified on site using a field herbarium prepared and developed by comparing samples with Queensland Herbarium samples and by using field handbooks and keys [60,61]. Any species not clearly identified on site were collected for later verification by Queensland Herbarium botanists.


**Table 1.** Description and diversity metrics of the heathland regional ecosystems on the Sunshine Coast, Queensland.

Regional Ecosystem, the species richness (SR), phylogenetic diversity (PD), mean phylogenetic distance (MPD), mean nearest taxon distance (MNTD), net relatedness index (NRI), and nearest taxon index (NTI) are given. Values that were significantly different from random (*p* = 0.05) are indicated with an asterisk. Superscript letters indicate whether these values are higher (\*H) or lower (\*L) than expected or whether they are significantly or clustered (\*C). No Regional Ecosystems were significantly even. Biodiversity status is that given by Queensland Herbarium assessments in 2018 [53].

For each species, a herbarium voucher and DNA sample in silica consisting of approximately 5 g of healthy, fresh, clean leaf material (permit numbers WITK 17429716 and WITK 18628117) were collected with vouchers lodged at Queensland Herbarium or the University of the Sunshine Coast Herbarium. Taxonomy used was the same as for the Queensland Flora Census [62]. A total of 255 vouched DNA samples was collected.

A complete list of Sunshine Coast heath plants comprising 366 species was compiled for later analysis, which included the species encountered on site, along with other species listed in local guidebooks [60,61,63,64] and confirmed through the Australian Virtual Herbarium [65].

**Figure 1.** Map of Queensland [66], Australia indicating the Sunshine Coast study area. In the expanded box, the Sunshine Coast area showing the location of the 80 sites. Sites are marked by their NRI results: phylogenetically clustered, random, or even.
