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Ecological restoration is addressing the challenge of biodiversity conservation in landscapes where native vegetation has been extensively cleared. Reestablishing ecological interactions that support self‐sustainable populations plays an essential role in restoration efforts. For animal‐pollinated plant species, comparing mating system dynamics within restoration populations with natural remnant populations can inform the progress of restoration activities. We assessed mating system parameters, seed weight, invertebrate floral visitors, and genetic diversity for two restoration populations and two native reference remnant populations of the animal‐pollinated, woody shrub/tree, Hakea laurina (Proteaceae) in the Southwest Australian Floristic Region. There was no difference in outcrossing rates between the two sites (restoration and reference populations combined) or treatments (sites combined). However, one restoration population showed significantly lower outcrossing that was correlated with reduced seed weight, greater inbreeding, and significantly lower invertebrate richness and abundance compared to its nearby remnant population. In contrast, in the other restoration population, all measures were comparable to the reference remnant population. Local genetic diversity available in remnant populations was captured in both restoration populations. Limitations to pollinator services may be affecting mating patterns and potentially population fitness, in a younger restoration population with reduced proximity to remnant vegetation, which has a tall coplanted overstorey species and spatially aggregated individuals. We highlight these aspects of restoration populations as important areas of ongoing research that will impact the reestablishment of ecological interactions, and the assessment of mating system dynamics as a valuable tool to inform the current progress of restoration activities. [ABSTRACT FROM AUTHOR]

Ecological genetics can provide a novel contribution to assessing the achievement of restoration objectives. We used paternity assignment to infer realized pollen dispersal within, and pollen immigration into, a restoration population of Hakea nitida, a common near‐coastal shrub or small tree in southwest Australia. We compared mating system parameters and genetic diversity with a nearby remnant reference population and assessed genetic divergence among the restoration and reference populations. We found realized pollen dispersal events closely tracked the frequency distributions of the distances between all plants within the restoration focus area. Mean realized pollen dispersal distance (359 m) approached the mean of the distances between all plants (407 m), far exceeding mean nearest neighbor distance (12 m). Maximum realized pollen dispersal distance (869 m) approached the maximum distance between all plants in the study area (1,033 m). Pollen immigration into the restoration study area was limited (4%). The mating system revealed moderate outcrossing rates (tm = 0.861 restoration and tm = 0.745 reference population), with significant and similar biparental inbreeding (tm − ts = 0.180, tm− ts = 0.186) but greater correlated paternity (rpm) in the restoration (0.519) than in the reference (0.188) population. Genetic divergence among the restoration and reference remnant population was moderate (FST = 0.094, DST = 0.239). Patterns of pollen dispersal and mating system parameters imply the attraction of pollinators within the restoration population as a key factor in progressing towards the establishment of self‐sustaining populations. [ABSTRACT FROM AUTHOR]

Indigenous societies' interactions with plants may result in contemporary distribution patterns that reflect these relationships, such as concentration of resource species close to occupation sites or transport routes. Seeds of the cycad, Macrozamia dyeri, are food of Nyungar First People of the south‐eastern Southwest Australian Floristic Region. Processing of seeds by leaching in soil or water enables detoxification and preservation of the pre‐colonial staple, a Nyungar technique archaeologically dated to at least 13 000 years BP. We measured the distance of M. dyeri populations to cultural landscape features and registered heritage sites. We also compared within‐population plant distribution characteristics to Nyungar occupation preferences around granite inselbergs. We found evidence of Nyungar influence on contemporary distribution of M. dyeri. Populations of M. dyeri occur close to surface water features in the west and granite outcrops in the east of Nyungar country, which corresponds closely to differential pre‐colonial patterns of Nyungar occupation. M. dyeri population frequency was negatively correlated with distance to registered Nyungar sites, and 75% of all M. dyeri populations occur within 3.2 km of a registered Nyungar site. We found no correlation between habitat availability and size of granite populations, but found that Nyungar occupation preferences in relation to ground surface aspect, slope and landform type correlated with intra‐population M. dyeri plant distribution, suggesting a mutualistic relationship with Nyungar people, has influenced the plant's distribution. We suggest that contemporary M. dyeri distribution is therefore useful for interpreting past location‐specific Nyungar land practices to inform contemporary conservation management. Our findings demonstrate that along with edaphic, climate and other environmental factors, consideration of pre‐colonial human dispersal and land practices is important for plant conservation in Australia, particularly for taxa with prolonged use by humans. Further, we suggest that analyses of long‐lived Macrozamia elsewhere may be useful for interpreting past Aboriginal land practices. [ABSTRACT FROM AUTHOR]

Pollination by nectarivorous birds is predicted to result in different patterns of pollen dispersal and plant mating compared to pollination by insects. We tested the prediction that paternal genetic diversity, outcrossing rate and realized pollen dispersal will be reduced when the primary pollinator group is excluded from bird‐pollinated plants. Pollinator exclusion experiments in conjunction with paternity analysis of progeny were applied to Eucalyptus caesia Benth. (Myrtaceae), a predominantly honeyeater‐pollinated tree that is visited by native insects and the introduced Apis mellifera (Apidae). Microsatellite genotyping at 14 loci of all adult E. caesia at two populations (n = 580 and 315), followed by paternity analysis of 705 progeny, revealed contrasting results between populations. Honeyeater exclusion did not significantly impact pollen dispersal or plant mating at Mount Caroline. In contrast, at the Chiddarcooping site, the exclusion of honeyeaters led to lower outcrossing rates, a threefold reduction in the average number of sires per fruit, a decrease in intermediate‐distance mating and an increase in near‐neighbour mating. The results from Chiddarcooping suggest that bird pollination may increase paternal genetic diversity, potentially leading to higher fitness of progeny and favouring the evolution of this strategy. However, further experimentation involving additional trees and study sites is required to test this hypothesis. Alternatively, insects may be effective pollinators in some populations of bird‐adapted plants, but ineffective in others. [ABSTRACT FROM AUTHOR]

Acacia cyclops, or Ngaamarur, is a common coastal shrub or small tree of the southwest of Western Australia and South Australia used for restoration in these landscapes and elsewhere. Knowledge of genetic diversity and mating systems of restoration populations is often lacking but can help inform likely restoration success. We compared genetic diversity and mating system parameters at three restoration populations of A. cyclops to nearby remnant reference populations. Mean levels of genetic diversity in restoration populations (Na = 1.806, Ne = 1.560, He = 0.270, Ho = 0.359) were not significantly different from those in the reference populations (Na = 1.833, Ne = 1.574, He = 0.269, Ho = 0.352) suggesting diverse seed collections were made for restoration. Allelic genetic divergence among restoration and reference populations was low (DST ≤ 0.04) suggesting that seeds were of local provenance. Mating system parameters were similar among restoration (tm = 0.989, tm–ts = 0.010, rpm = 0.392) and reference populations (tm = 0.868, tm–ts = 0.039, rpm = 0.410), suggesting functionality of the mating system and restitution of generalist insect pollinator services in restored populations at 7, 10, and 12 years after planting. Lower levels of heterozygosity in progeny compared to adults suggest post‐germination or late‐acting selection against inbred seedlings. Evidence for selection and seedling attrition further emphasizes the benefits of collections from many individuals in well‐connected outcrossed source populations. Overall, results suggest available local genetic diversity was captured and restoration populations have mating systems equivalent to those of reference populations. [ABSTRACT FROM AUTHOR]

Historically fragmented and specialized habitats such as granite outcrops are understudied globally unique hot spots of plant evolution. In contrast to predictions based on mainstream population genetic theory, some granite outcrop plants appear to have persisted as very small populations despite prolonged geographic and genetic isolation. Eucalyptus caesia Benth. is a long‐lived lignotuberous tree endemic with a naturally fragmented distribution on granite outcrops in south‐western Australia. To quantify population to landscape‐level genetic structure, we employed microsatellite genotyping at 14 loci of all plants in 18 stands of E. caesia. Sampled stands were characterized by low levels of genetic diversity, small absolute population sizes, localized clonality and strong fine‐scale genetic subdivision. There was no significant relationship between population size and levels of heterozygosity. At the landscape scale, high levels of population genetic differentiation were most pronounced among representatives of the two subspecies in E. caesia as originally circumscribed. Past genetic interconnection was evident between some geographic neighbours separated by up to 20 km. Paradoxically, other pairs of neighbouring stands as little as 7 km apart were genetically distinct. There was no consistent pattern of isolation by distance across the 280 km range of E. caesia. Low levels of gene flow, together with strong drift within stands, provide some explanation of the patterns of genetic differentiation we observed. Individual genet longevity via the ability to repeatedly resprout and expand from a lignotuber may enhance the persistence of some woody perennial endemic plants despite small population size, minimal genetic interconnection and low heterozygosity. [ABSTRACT FROM AUTHOR]

Determining patterns of plant diversity on granite inselbergs is an important task for conservation biogeography due to mounting threats. However, beyond the tropics there are relatively few quantitative studies of floristic diversity, or consideration of these patterns and their environmental, biogeographic, and historical correlates for conservation. We sought to contribute broader understanding of global patterns of species diversity on granite inselbergs and inform biodiversity conservation in the globally significant Southwest Australian Floristic Region (SWAFR). We surveyed floristics from 16 inselbergs (478 plots) across the climate gradient of the SWAFR stratified into three major habitats on each outcrop. We recorded 1,060 species from 92 families. At the plot level, local soil and topographic variables affecting aridity were correlated with species richness in herbaceous (HO) and woody vegetation (WO) of soil‐filled depressions, but not in woody vegetation on deeper soils at the base of outcrops (WOB). At the outcrop level, bioclimatic variables affecting aridity were correlated with species richness in two habitats (WO and WOB) but, contrary to predictions from island biogeography, were not correlated with inselberg area and isolation in any of the three habitats. Species turnover in each of the three habitats was also influenced by aridity, being correlated with bioclimatic variables and with interplot geographic distance, and for HO and WO habitats with local site variables. At the outcrop level, species replacement was the dominant component of species turnover in each of the three habitats, consistent with expectations for long‐term stable landscapes. Our results therefore highlight high species diversity and turnover associated with granite outcrop flora. Hence, effective conservation strategies will need to focus on protecting multiple inselbergs across the entire climate gradient of the region. [ABSTRACT FROM AUTHOR]

Aim Although all five of the major mediterranean-climate ecosystems (MCEs) of the world are recognized as loci of high plant species diversity and endemism, they show considerable variation in regional-scale richness. Here, we assess the role of stable Pleistocene climate and Cenozoic topography in explaining variation in regional richness of the globe's MCEs. We hypothesize that older, more climatically stable MCEs would support more species, because they have had more time for species to accumulate than MCEs that were historically subject to greater topographic upheavals and fluctuating climates. Location South-western Africa (Cape), south-western Australia, California, central Chile and the eastern (Greece) and western (Spain) Mediterranean Basin. Methods We estimated plant diversity for each MCE as the intercepts of species-area curves that are homogeneous in slope across all regions. We used two down-scaled global circulation models of the Last Glacial Maximum (LGM) to quantify climate stability by comparing the change in the location of MCEs between the LGM and present. We quantified the Cenozoic topographic stability of each MCE by comparing contemporary topographic profiles with those present in the late Oligocene and the early Pliocene. Results The most diverse MCEs - Cape and Australia - had the highest Cenozoic environmental stability, and the least diverse - Chile and California - had the lowest stability. Main conclusions Variation in plant diversity in MCEs is likely to be a consequence not of differences in diversification rates, but rather the persistence of numerous pre-Pliocene clades in the more stable MCEs. The extraordinary plant diversity of the Cape is a consequence of the combined effects of both mature and recent radiations, the latter associated with increased habitat heterogeneity produced by mild tectonic uplift in the Neogene. [ABSTRACT FROM AUTHOR]

Aim Granite outcrops may be able to act as refugia for species during adverse climate change, owing to their topographic complexity. We assessed this hypothesis by examining phylogeographical patterns in a common, geographically widespread granite endemic, Stypandra glauca (Hemerocallidaceae). Location Granite outcrops of the Southwest Australian Floristic Region, Western Australia. Methods Twenty-four tetraploid individuals of the granite endemic Stypandra glauca were sampled from each of 12 granite outcrops: 7 from a mesic environment and 5 from the semi-arid region. Phylogenetic reconstruction and divergence-dating was achieved using Bayesian and parsimony analyses of chloroplast haplotypes from 90 individuals. Nuclear diversity and population differentiation were analysed across all individuals using 10 microsatellite loci. Results Stypandra glauca exhibited high (chloroplast) or moderate (nuclear) levels of divergence among, and low diversity within, outcrops. Haplotype diversity was high in both sampling regions, and each haplotype was unique to one outcrop. There was little correlation between geographical and genetic distance. Both nuclear and chloroplast diversity were higher in southern (mesic) outcrops than in northern (semi-arid) outcrops, although the level of chloroplast divergence among outcrops was similar for both climatic regions. Main conclusions The levels of divergence and low diversity revealed in S. glauca support a scenario of prolonged isolation and persistence on granite outcrops in both mesic and semi-arid climatic regions, with no evidence of contraction-expansion dynamics across the outcrop network. The higher levels of diversity in the southern populations may result from the maintenance of a larger effective population size in southern regions, which retained more mesic climates during drier glacial periods. Although the climatic conditions differ between outcrops in this study, our results indicate that outcrops in both regions have harboured S. glauca throughout climatic changes, accentuating the value of these habitats to biodiversity conservation under future changing climate. [ABSTRACT FROM AUTHOR]

ABSTRACT Aim Identifying and protecting refugia is a priority for conservation under projected anthropogenic climate change, because of their demonstrated ability to facilitate the survival of biota under adverse conditions. Refugia are habitats that components of biodiversity retreat to, persist in and can potentially expand from under changing environmental conditions. However, the study and discussion of refugia has often been ad hoc and descriptive in nature. We therefore: (1) provide a habitat-based concept of refugia, and (2) evaluate methods for the identification of refugia. Location Global. Methods We present a simple conceptual framework for refugia and examine the factors that describe them. We then demonstrate how different disciplines are contributing to our understanding of refugia, and the tools that they provide for identifying and quantifying refugia. Results Current understanding of refugia is largely based on Quaternary phylogeographic studies on organisms in North America and Europe during significant temperature fluctuations. This has resulted in gaps in our understanding of refugia, particularly when attempting to apply current theory to forecast anthropogenic climate change. Refugia are environmental habitats with space and time dimensions that operate on evolutionary time-scales and have facilitated the survival of biota under changing environmental conditions for millennia. Therefore, they offer the best chances for survival under climate change for many taxa, making their identification important for conservation under anthropogenic climate change. Several methods from various disciplines provide viable options for achieving this goal. Main conclusions The framework developed for refugia allows the identification and description of refugia in any environment. Various methods provide important contributions but each is limited in scope; urging a more integrated approach to identify, define and conserve refugia. Such an approach will facilitate better understanding of refugia and their capacity to act as safe havens under projected anthropogenic climate change. [ABSTRACT FROM AUTHOR]

While rarely tested, the rarity of a species may be linked to the rarity of symbiotic partners. The requirement of many terrestrial plants to form a symbiosis with mycorrhizal fungi may limit the distribution and abundance of plant species. Here, in just the second test of the role of mycorrhiza in host species rarity, we investigate the influence of mycorrhizal specificity, distribution and ecological requirements in the genus Drakaea (Orchidaceae). In situ seed baiting was used to resolve the distribution of mycorrhizal fungi for three common and two co-occurring rare species of Drakaea. Mycorrhizal fungi were isolated from wild adult orchids and protocorms and the ITS nrDNA regions sequenced. An in vitro study tested the range of Drakaea species of which each fungus can support germination. All Drakaea species studied used a narrow monophyletic clade of Tulasnella endophyte for protocorm, seedling and adult plant stages. In situ seed baiting revealed that germination of Drakaea is largely restricted to the same microhabitat as that of the orchid. However, within this habitat Drakaea exhibit comparable germination to other Western Australian orchid genera. Rare and common Drakaea exhibited no difference in germination rates and both germinated in suitable habitat not currently occupied. Synthesis. In contrast to the previous study of the role of mycorrhiza in plant rarity, there was no evidence that mycorrhizal specificity contributed to rarity in Drakaea. However, the formation of mycorrhiza being mostly restricted to a specific microhabitat may limit the abundance of Drakaea in some landscapes. In Drakaea, the highly specific pollination system of sexual deception may contribute to rarity. A trend towards high specificity in orchid mycorrhizal associations in southern Australia is hypothesized to result from the predominance of old landscapes affording the opportunity for specialization on a single or few mycorrhiza(s) best adapted to the landscape conditions. [ABSTRACT FROM AUTHOR]

The causes of orchid diversification and intrinsic rarity are poorly resolved. The Orchidaceae of the Southwest Australian Floristic Region use a diversity of pollination strategies and sites of mycorrhizal infection, and occupy a diversity of habitats. We combined a biogeographic analysis with analysis of factors associated with rarity to establish: (1) the landscape features correlated with taxon turnover and speciation, and (2) the possible role in taxon rarity of geographic region, pollination strategy, edaphic habitat and site of mycorrhizal infection. Southwest Australian Floristic Region. The distributions of 407 orchid taxa (species and subspecies) were mapped at the quarter-degree scale using 13,267 collections in the Western Australian Herbarium. This database was used to map taxon richness, for a biogeographic analysis and to quantify rarity of taxa. Using herbarium records, rarity was expressed as mean abundance, mean distribution and incidence of rarity based on abundance and distribution for each genus. We tested for differences in rarity of species between pollination strategies, edaphic habitats and sites of mycorrhizal infection. Taxon richness was highest in the High Rainfall Province. Biogeographic provincial boundaries for orchids were aligned with rainfall, while district boundaries tended to follow geological formations. When rarity was defined as either low abundance or small distribution, the greatest number of rare taxa occurred in areas of high taxon richness and naturally fragmented edaphic environments. For both abundance and distributional extent, sexual deception had a significantly higher incidence of rarity than food-rewarding taxa. There was no significant difference in rarity with site of mycorrhizal infection. While large-scale edaphic and climatic variation are correlated with orchid taxon turnover and speciation in a similar fashion to the flora in general, the processes responsible for patterns of diversity may differ. Fragmented edaphic environments appear to be associated with a higher incidence of rare species due to limited dispersal/colonization opportunities or radiations of taxa in allopatry. The high incidence of rarity in sexually deceptive taxa could be due to either low fruit set or the risk of specializing on a single pollinator species. [ABSTRACT FROM AUTHOR]

Summary. Nuytsia floribunda (Labill.) R.Br. ex G.Don, a monotypic arborescent root hemiparasite endemic to the Southwest Australian Floristic Region, sister to all other showy mistletoes, is described and illustrated. A review is provided of its mythological and practical use by Noongar Aborigines, its discovery and early documentation by Europeans, and its phylogeny, biology, ecology and systematics. Experiences with its cultivation and propagation before and after it was discovered to be parasitic are discussed. Nuytsia provides a useful case study for testing many hypotheses developed in OCBIL theory, which aims to explain the evolution and ecology of, and best conservation practices for, biota on very old, climatically buffered, infertile landscapes (i.e. OCBILs), found especially in regions such as the Southwest Australian Floristic Region, the Greater Cape of South Africa and the Pantepui of Venezuela. [ABSTRACT FROM AUTHOR]

Part II. Discusses the history, discovery, collection and naming of the south-western Australian flora. How the full extent of the diversity of the region's flora had been hidden and revealed only during the last 20 years; French scientific expedition led by Thomas Nicholas Baudin; Achievements of early post-settlement botanical contributors; Discoveries in the past three decades.

Explores the diversity of plants in Australia. Presence of nutrient-deficient sands; Systematic relationships of plants.

The taxonomy, distribution and horticulture of the south-west Australian endemic Anigozanthos rufus Labill. (Haemodoraceae) are discussed. Illustrations and a description of the species are provided. [ABSTRACT FROM AUTHOR]

The taxonomy, distribution and horticulture of the south-west Australian endemic Caladenia drummondii Benth. (Orchidaceae) are discussed, including a brief account of recent insights from molecular pbylogenetic research on the subtribe Caladeniinac and circumscription of the genus Caladenia. Illustrations and a description of C. drummondii are provided. [ABSTRACT FROM AUTHOR]

In seasonally dry regions of the world fire is a recurring disturbance but little is known of how fire interacts with granite outcrop vegetation. We hypothesize that the floristic composition in granite vegetation, usually attributed to the edaphic environment, may also reflect the impact of disturbances such as fire. Dramatic differences in floristic composition and cover over 13 years and two fires were observed in vegetation on a Western Australian granite outcrop. This was very marked in the first year following the two fires, with annuals and geophytes showing the greatest turnover of species. Even among the perennial shrubs there was considerable turnover in a number of obligate seeders. After the first fire the number of species declined for woody perennials, herbaceous perennials and annuals, remained unchanged for perennial grasses and sedges, and varied with highest richness 4 yr after fire for geophytes. Demographic studies of two endemic woody obligate seeders and three endemic mallee eucalypt resprouters similarly showed dramatic differences within and between species in seedling recruitment following the two fires. Fire does have a significant impact on the floristic composition of semi-arid granite outcrop vegetation communities. Studies on other granite outcrop systems are needed to test the generality of this conclusion. [ABSTRACT FROM AUTHOR]

Presents a study that used DNA sequence data from plastid matK and trnL-F regions in phylogenetic analyses of Diurideae. Background on Diurideae, a southern Hemisphere species of terrestrial orchids; Methodology; Results and discussion.

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