43 research outputs found

    Waratah theft in Brisbane Water National Park - an analysis of the blue paint poaching reduction program

    Get PDF
    The flowers of Waratahs, Telopea speciosissima (family Proteaceae) are regularly harvested illegally from natural bushland, particularly close to urban areas such as the New South Wales Central Coast. The removal of Waratah blooms from the wild may have implications for the long-term survival of local populations because of the interaction between wildfire events, subsequent flowering and limited seedling recruitment opportunities. To reduce the incidence of theft, blue acrylic paint was applied to blooms to reduce their commercial value. The painting of blooms in 2004 did not significantly reduce the incidence of wildflower theft when compared to unpainted blooms, but overall losses were lower (27%) than in 2003 (33%). However, painting of blooms had a deleterious affect on fruit production on plants with multiple heads with painted blooms having significantly reduced fruit set compared to unpainted blooms. Painting of blooms had no significant effect on seed quality (seed production per fruit, seed germination or seedling vigour) when compared to unpainted blooms. The painting of Waratah blooms to reduce theft was relatively ineffective and decreased fruit production. Alternative strategies should be considered to reduce wildflower theft in the area

    The impact of distance and a shifting temperature gradient on genetic connectivity across a heterogeneous landscape

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Inter-population distance and differences in breeding times are barriers to reproduction that can contribute to genotypic differentiation between populations. Temporal changes in environmental conditions and local selective processes can further contribute to the establishment of reproductive barriers. <it>Telopea speciosissima </it>(Proteaceae) is an excellent subject for studying the effect of geographic, edaphic and phenological heterogeneity on genotypic differentiation because previous studies show that these factors are correlated with morphological variation. Molecular, morphological and environmental datasets were combined to characterise the relative influence of these factors on inter-population differentiation, and Bayesian analyses were used to investigate current levels of admixture between differentiated genomes.</p> <p>Results</p> <p>A landscape genetic approach involving molecular and morphological analyses identified three endpoints of differentiated population groups: coastal, upland and southern. The southern populations, isolated from the other populations by an edaphic barrier, show low migration and no evidence of admixture with other populations. Amongst the northern populations, coastal and upland populations are connected along a skewed altitudinal gradient by genetically intermediate populations. The strong association between temperature and flowering time in <it>Telopea speciosissima </it>was shown to maintain a temporally unstable reproductive barrier between coastal and upland populations.</p> <p>Conclusions</p> <p>Substrate-mediated allopatry appears to be responsible for long-term genetic isolation of the southern populations. However, the temperature-dependent reproductive barrier between upland and coastal populations bears the genetic signature of temporal adjustments. The extreme climatic events of the last glacial maximum are likely to have caused more complete allochronic isolation between upland and coastal populations, as well as exerting increased selective pressure upon local genomes. However, at intermediate altitudes, current climatic conditions allow for the incorporation of alleles from previously distinct genomes, generating new, intermediate genomic assemblages and possibly increasing overall adaptive potential.</p

    Understanding seed dormancy and germination aids conservation of rainforest species from tropical montane cloud forest: a case study confirming morphophysiological dormancy in the genus Tasmannia

    Get PDF
    Context: Seed dormancy is one issue hindering implementation of conservation actions for rainforest species. Aims: We studied dormancy and germination in Tasmannia sp. Mt Bellenden Ker and Tasmannia membranea, two tropical montane rainforest species threatened by climate change, to develop a better understanding of dormancy in the species and the genus. Methods: Dormancy was classified for T. sp. Mt Bellenden Ker on the basis of an imbibition test, analysis of embryo to seed length (E:S) ratios and germination in response to the following four dormancy-breaking treatments: (I) scarification of the seedcoat near the micropylar end; (2) removal of the seedcoat; (3) application of 100 mg L(-1)or (4) 500 mg L-1 gibberellic acid. The most effective treatment was then tested on T. membranea. The requirement for light for germination was also assessed. Key results: Both scarified and intact seeds imbibed water. Initial E:S ratios were <0.22 for both species and increased up to 0.74 after 40 days, just before radicle emergence, for T. sp. Mt Bellenden Ker. Germination proportions were significantly higher in Treatments 1 and 2 than the remaining treatments for T. sp. Mt Bellenden Ker; T. membranea responded similarly well to Treatment 1. Germination under alternating light/dark conditions was slightly, but not significantly, greater than germination in the dark alone. Conclusions: Both species have morphophysiological dormancy and treatments that remove seedcoat resistance to embryo growth facilitate germination. These treatments may improve germination in other species from the genus Tasmannia. Implications: This knowledge will aid the germination of seeds to implement conservation strategies for Tasmannia spp

    Seed fill, viability and germination of NSW species in the family Rutaceae

    No full text
    The New South Wales Seedbank (at Mount Annan Botanic Garden) stores seeds of both common and threatened species for conservation, research and restoration or revegetation projects. The value of the collections depends on our ability to germinate seeds once they have been retrieved from storage. The collection includes 129 collections representing 93 taxa in the family Rutaceae, but seed viability in Rutaceae is variable, germination cues are poorly-understood and problems are likely to arise in trying to grow plants from seed. In this study we quantified seed fill and/or viability and germination for 112 species in the Rutaceae family. For many of the species, this is the first time that these seed characteristics have been recorded. We found that seed fill (0–100%) and seed viability (0–97%), were highly variable, with 80% of collections having low viability (<75%). There was also a trend for threatened species to have lower seed fill than common species, while viability and germination were similar. This review reaffirms the need for further study of seed characteristics in Rutaceae

    Defining biodiverse reforestation: Why it matters for climate change mitigation and biodiversity

    Get PDF
    Mixed species plantings present an attractive alternative to monoculture reforestation through their added benefits to biodiversity. Yet there is ambiguity in the use of the term ‘biodiversity’ in carbon and biodiversity markets, which may create perverse outcomes when designing schemes and projects. Here, we review how the concept of biodiversity is defined and applied in reforestation projects, and restoration more broadly. Improved transparency around the use of the term biodiversity is urgently needed to provide rigour in emerging market mechanisms, which seek to benefit the environment and people. Summary: Reforestation to capture and store atmospheric carbon is increasingly championed as a climate change mitigation policy response. Reforestation plantings have the potential to provide conservation co-benefits when diverse mixtures of native species are planted, and there are growing attempts to monetise biodiversity benefits from carbon reforestation projects, particularly within emerging carbon markets. But what is meant by ‘biodiverse’ across different stakeholders and groups implementing and overseeing these projects and how do these perceptions compare with long-standing scientific definitions? Here, we discuss approaches to, and definitions of, biodiversity in the context of reforestation for carbon sequestration. Our aim is to review how the concept of biodiversity is defined and applied among stakeholders (e.g., governments, carbon certifiers and farmers) and rights holders (i.e., First Nations people) engaging in reforestation, and to identify best-practice methods for restoring biodiversity in these projects. We find that some stakeholders have a vague understanding of diversity across varying levels of biological organisation (genes to ecosystems). While most understand that biodiversity underpins ecosystem functions and services, many stakeholders may not appreciate the difficulties of restoring biodiversity akin to reference ecosystems. Consequently, biodiversity goals are rarely explicit, and project goals may never be achieved because the levels of restored biodiversity are inadequate to support functional ecosystems and desired ecosystem services. We suggest there is significant value in integrating biodiversity objectives into reforestation projects and setting specific restoration goals with transparent reporting outcomes will pave the way for ensuring reforestation projects have meaningful outcomes for biodiversity, and legitimate incentive payments for biodiversity and natural capital accounting

    Managing Persoonia (Proteaceae) species in the landscape through a better understanding of their seed biology and ecology

    No full text
    Persoonia (family Proteaceae) is a diverse genus of 99 species, mainly of woody shrubs and small trees, that are endemic to Australia. The fleshy fruits that characterise these plants are an important resource in otherwise resource-depauperate ecological communities. However, this genus is highly under-represented in restoration and conservation programs, as its species are notoriously difficult to propagate and transplant in the wild. Understanding the mechanisms that control seed production, viability, dormancy and germination will hasten progress on Persoonia propagation. Here we review Persoonia studies to reveal the nature of, and variability within, the genus. We identify key factors that need to be addressed; specifically, those affecting fruit set, endocarp degradation and subsequent propagation of Persoonia. This synthesis of current knowledge provides important material to inform management of this taxon in the landscape, and outlines several important priorities for future seed biology research on the genus. We outline several important priorities for future seed biology research on the genus

    Leaf morphological traits show greater responses to changes in climate than leaf physiological traits and gas exchange variables.

    Get PDF
    Adaptation to changing conditions is one of the strategies plants may use to survive in the face of climate change. We aimed to determine whether plants' leaf morphological and physiological traits/gas exchange variables have changed in response to recent, anthropogenic climate change. We grew seedlings from resurrected historic seeds from ex-situ seed banks and paired modern seeds in a common-garden experiment. Species pairs were collected from regions that had undergone differing levels of climate change using an emerging framework-Climate Contrast Resurrection Ecology, allowing us to hypothesise that regions with greater changes in climate (including temperature, precipitation, climate variability and climatic extremes) would be greater trait responses in leaf morphology and physiology over time. Our study found that in regions where there were greater changes in climate, there were greater changes in average leaf area, leaf margin complexity, leaf thickness and leaf intrinsic water use efficiency. Changes in leaf roundness, photosynthetic rate, stomatal density and the leaf economic strategy of our species were not correlated with changes in climate. Our results show that leaves do have the ability to respond to changes in climate, however, there are greater inherited responses in morphological leaf traits than in physiological traits/variables and greater responses to extreme measures of climate than gradual changes in climatic means. It is vital for accurate predictions of species' responses to impending climate change to ensure that future climate change ecology studies utilise knowledge about the difference in both leaf trait and gas exchange responses and the climate variables that they respond to

    A comparative study of seed morphology in relation to desiccation tolerance and other physiological responses in 71 Eastern Australian Rainforest species

    No full text
    Seed characteristics were measured in 71 Eastern Australian rainforest species representing 30 families. Sensitivity to desiccation to low moisture contents (\u3c 10%) occurred in 42% of species. We estimate, based on findings from 100 species from this present study and previously published reports, that 49% of Eastern Australian rainforest species have non-orthodox seeds. Germination level and time to 50% germination were not significantly different between desiccation sensitive (DS) and desiccation tolerant (DT) seeds. The estimation of seed desiccation sensitivity based on predictors is an important tool underpinning ex situ conservation efforts. Seed characteristics differed significantly between DS and DT seeds; that is, DS seeds had: (i) larger fruits (19 949 mg vs 8322 mg); (ii) larger seeds (1663 mg vs 202 mg); (iii) higher seed moisture contents (49.7% vs 35.5% fresh weight); (iv) lower oil content (7.3% vs 24.8% yield); and (v) less investment in seed coats (0.19 vs 0.48 seed coat ratio). Only 25% of DS seeded species had oily seeds compared with 87% of DT seeded species. Most green embryos were DS. Seed coat ratio was the best predictor of seed DS (80% correctly predicted). Seed moisture content at maturity was also related to germination time. Mean seed size was correlated (−0.657, P = 0.01) with mean seed oil content in 46 species. Further research on seed storage physiology of possible oily and/or DS seeded species is crucial to ensure future long-term security of this biodiversity, particularly for species currently threatened in situ and/or of socioeconomic importance in Eastern Australian rainforests

    Seed fill, viability and germination of NSW species in the family Rutaceae

    No full text
    Abstract: The New South Wales Seedbank (at Mount Annan Botanic Garden) stores seeds of both common and threatened species for conservation, research and restoration or revegetation projects. The value of the collections depends on our ability to germinate seeds once they have been retrieved from storage. The collection includes 129 collections representing 93 taxa in the family Rutaceae, but seed viability in Rutaceae is variable, germination cues are poorly-understood and problems are likely to arise in trying to grow plants from seed. In this study we quantified seed fill and/or viability and germination for 112 species in the Rutaceae family. For many of the species, this is the first time that these seed characteristics have been recorded. We found that seed fill (0-100%) and seed viability (0-97%), were highly variable, with 80% of collections having low viability (\u3c75%). There was also a trend for threatened species to have lower seed fill than common species, while viability and germination were similar. This review reaffirms the need for further study of seed characteristics in Rutaceae
    corecore