ORCID Profile
0000-0003-2979-4505
Current Organisation
Murdoch University
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Macromolecular and Materials Chemistry | Synthesis of Materials |
Expanding Knowledge in the Chemical Sciences | Expanding Knowledge in Technology
Publisher: Wiley
Date: 06-2010
Publisher: Wiley
Date: 28-07-2006
Publisher: Wiley
Date: 30-08-2005
Publisher: Informa UK Limited
Date: 06-1996
Publisher: Wiley
Date: 1989
Publisher: Wiley
Date: 04-2001
Publisher: Wiley
Date: 06-2003
Publisher: Wiley
Date: 09-2009
Publisher: Wiley
Date: 09-2007
DOI: 10.1890/06-1343.1
Abstract: The fire-prone shrublands of southwestern Australia are renowned for their high plant species ersity and prominence of canopy seed storage (serotiny). We compared species richness, abundance, and life history attributes for soil and canopy seed banks in relation to extant vegetation among four sites with different substrate conditions and high species turnover (50-80%) to identify whether this unusual community-level organization of seed storage might contribute to maintenance of high species richness. Soil seed bank (SSB) densities were low to moderate (233-1435 seeds/m2) compared with densities for other Mediterranean-type vegetation and were lowest for sites with highest canopy seed bank (CSB) species richness and lowest nutrient availability, but not richness or abundance of resprouters. Annuals were infrequent in the lowest nutrient sites, but there was no evidence that small SSB size was due to low seed inputs or a trade-off between seed production/storage and seed size in response to low nutrient availability. Sorensen's similarity between SSB and extant vegetation was 26-43% but increased to 54-57% when the CSB was included, representing levels higher than reported for most other ecosystems. Resprouting species were well represented in both the SSB and CSB, and there was no evidence for lower seed production in resprouters than in non-sprouters overall. The SSB and CSB held no species in common and were characterized by markedly different seed dispersal attributes, with winged or small seeds in the CSB and seeds dispersed by ants, birds, and wind (though none with wings) in the SSB. There was no evidence of spatial differentiation in the distribution of seeds of SSB species between vegetated and open microsites that might facilitate species coexistence, but most woody non-sprouters showed aggregation at scales of 1-2 m, implying limited seed dispersal. High similarity between overall seed bank (SSB + CSB) and extant species composition, high number of resprouting species, and seed dispersal processes before (SSB) and after fire (CSB) leading to differential spatial aggregation of post-fire recruits from the two seed bank types may buffer species composition against rapid change and provide a mechanism for maintaining species coexistence at the local scale.
Publisher: Wiley
Date: 29-01-2008
DOI: 10.3170/2008-8-18441
Publisher: Elsevier BV
Date: 06-2018
Publisher: Wiley
Date: 12-1985
Publisher: Wiley
Date: 06-11-2007
Publisher: Wiley
Date: 30-09-2019
Publisher: Springer Science and Business Media LLC
Date: 23-05-2016
DOI: 10.1038/SREP26315
Abstract: Substantial climate changes are evident across Australia, with declining rainfall and rising temperature in conjunction with frequent fires. Considerable species loss and range contractions have been predicted however, our understanding of how genetic variation may promote adaptation in response to climate change remains uncertain. Here we characterized candidate genes associated with rainfall gradients, temperatures and fire intervals through environmental association analysis. We found that overall population adaptive genetic variation was significantly affected by shortened fire intervals, whereas declining rainfall and rising temperature did not have a detectable influence. Candidate SNPs associated with rainfall and high temperature were erse, whereas SNPs associated with specific fire intervals were mainly fixed in one allele. Gene annotation further revealed four genes with functions in stress tolerance, the regulation of stomatal opening and closure, energy use and morphogenesis with adaptation to climate and fire intervals. B. attenuata may tolerate further changes in rainfall and temperature through evolutionary adaptations based on their adaptive genetic variation. However, the capacity to survive future climate change may be compromised by changes in the fire regime.
Publisher: JSTOR
Date: 09-1989
DOI: 10.2307/3566085
Publisher: Informa UK Limited
Date: 12-1991
Publisher: Springer Science and Business Media LLC
Date: 14-11-2018
DOI: 10.1038/S41467-018-06649-5
Abstract: The total number of acquired melanocytic nevi on the skin is strongly correlated with melanoma risk. Here we report a meta-analysis of 11 nevus GWAS from Australia, Netherlands, UK, and USA comprising 52,506 in iduals. We confirm known loci including MTAP , PLA2G6 , and IRF4 , and detect novel SNPs in KITLG and a region of 9q32. In a bivariate analysis combining the nevus results with a recent melanoma GWAS meta-analysis (12,874 cases, 23,203 controls), SNPs near GPRC5A, CYP1B1 , PPARGC1B , HDAC4 , FAM208B, DOCK8 , and SYNE2 reached global significance, and other loci, including MIR146A and OBFC1, reached a suggestive level. Overall, we conclude that most nevus genes affect melanoma risk ( KITLG an exception), while many melanoma risk loci do not alter nevus count. For ex le, variants in TERC and OBFC1 affect both traits, but other telomere length maintenance genes seem to affect melanoma risk only. Our findings implicate multiple pathways in nevogenesis.
Publisher: American Society for Microbiology
Date: 16-02-2023
DOI: 10.1128/IAI.00510-22
Abstract: Mycobacterium tuberculosis ( Mtb ) is a bacterium that exclusively resides in human hosts and remains a dominant cause of morbidity and mortality among infectious diseases worldwide. Host protection against Mtb infection is dependent on the function of immunity-related GTPase clade M (IRGM) proteins.
Publisher: Public Library of Science (PLoS)
Date: 29-11-2012
Publisher: JSTOR
Date: 12-1989
DOI: 10.2307/2260826
Publisher: CSIRO Publishing
Date: 2015
DOI: 10.1071/BT15041
Abstract: Seedlings of Xanthorrhoea glauca subsp. angustifolia D.J.Bedford (Xanthorrhoeaceae) were grown in burnt, unburnt and ash-rich soils from the box-ironbark ecosystem, northern central Victoria. Analysis of root architecture and the chemistry of leaves and roots demonstrate that burning improves seedling biomass development and acquisition of nutrients. An increased uptake of zinc by seedlings after fire is thought to be ecologically important and may infer vesicular-arbuscular mycorrhizal associations. The early development of a secondary root system is likely to contribute to seedling survivorship. Given the observed high adult mortality after managed fuel-reduction fires, the importance of understanding and manipulating recruitment dynamics through an adaptive and strategic fire management of the remaining populations is likely to define the long-term survival of the species in Victoria.
Publisher: Wiley
Date: 09-1982
Publisher: Wiley
Date: 12-08-2008
Publisher: Springer Science and Business Media LLC
Date: 05-07-2018
DOI: 10.1038/S41598-018-28160-Z
Abstract: Previous studies have shown an increased risk for mental health problems in children born to both younger and older parents compared to children of average-aged parents. We previously used a novel design to reveal a latent mechanism of genetic association between schizophrenia and age at first birth in women (AFB). Here, we use independent data from the UK Biobank (N = 38,892) to replicate the finding of an association between predicted genetic risk of schizophrenia and AFB in women, and to estimate the genetic correlation between schizophrenia and AFB in women stratified into younger and older groups. We find evidence for an association between predicted genetic risk of schizophrenia and AFB in women (P-value = 1.12E-05), and we show genetic heterogeneity between younger and older AFB groups (P-value = 3.45E-03). The genetic correlation between schizophrenia and AFB in the younger AFB group is −0.16 (SE = 0.04) while that between schizophrenia and AFB in the older AFB group is 0.14 (SE = 0.08). Our results suggest that early, and perhaps also late, age at first birth in women is associated with increased genetic risk for schizophrenia in the UK Biobank s le. These findings contribute new insights into factors contributing to the complex bio-social risk architecture underpinning the association between parental age and offspring mental health.
Publisher: Wiley
Date: 29-11-2014
Abstract: The development and screening of microsatellite markers have been accelerated by next-generation sequencing (NGS) technology and in particular GS-FLX pyro-sequencing (454). More recent platforms such as the PGM semiconductor sequencer (Ion Torrent) offer potential benefits such as dramatic reductions in cost, but to date have not been well utilized. Here, we critically compare the advantages and disadvantages of microsatellite development using PGM semiconductor sequencing and GS-FLX pyro-sequencing for two gymnosperm (a conifer and a cycad) and one angiosperm species. We show that these NGS platforms differ in the quantity of returned sequence data, unique microsatellite data and primer design opportunities, mostly consistent with the differences in read length. The strength of the PGM lies in the large amount of data generated at a comparatively lower cost and time. The strength of GS-FLX lies in the return of longer average length sequences and therefore greater flexibility in producing markers with variable product length, due to longer flanking regions, which is ideal for capillary multiplexing. These differences need to be considered when choosing a NGS method for microsatellite discovery. However, the ongoing improvement in read lengths of the NGS platforms will reduce the disadvantage of the current short read lengths, particularly for the PGM platform, allowing greater flexibility in primer design coupled with the power of a larger number of sequences.
Publisher: Informa UK Limited
Date: 06-2012
Publisher: Wiley
Date: 28-07-2006
Publisher: Wiley
Date: 08-04-2013
DOI: 10.1111/AEC.12045
Publisher: Springer Science and Business Media LLC
Date: 07-1983
DOI: 10.1007/BF00279492
Publisher: Springer Science and Business Media LLC
Date: 12-11-2008
DOI: 10.1038/HDY.2008.118
Abstract: In plants, pollen- and seed-dispersal distributions are characteristically leptokurtic, with significant consequences for spatial genetic structure and nearest-neighbour mating. However, most studies to date have been on wind- or insect-pollinated species. Here, we assigned paternity to quantify effective pollen dispersal over 9 years of mating, contrasted this to seed dispersal and examined their effects on fine-scale spatial genetic structure, within the bird-pollinated shrub Banksia hookeriana (Proteaceae). We used 163 polymorphic lified fragment length polymorphism markers to assess genetic structure and pollen dispersal in a spatially discrete population of 112 plants covering 0.56 ha. Spatial autocorrelation analysis detected spatial genetic structure in the smallest distance class of 0-5 m (r=0.025), with no significant structure beyond 8 m. Experimentally quantified seed-dispersal distances for 337 seedlings showed a leptokurtic distribution around a median of 5 m, reaching a distance of 36 m. In marked contrast, patterns of pollen dispersal for 274 seeds departed strikingly from typical near-neighbour pollination, with a distribution largely corresponding to the spatial distribution of plants. We found very high multiple paternity, very low correlated paternity and an equal probability of siring for the 50 closest potential mates. Extensive pollen carryover was demonstrated by multiple siring in 83 of 86 (96.5%) two-seeded fruits. Highly mobile nectar-feeding birds facilitate this promiscuity through observed movements that were effectively random. As the incidence of bird-pollination is markedly greater in the Southwest Australian Floristic Region than elsewhere, our results have broad and novel significance for the evolution and conservation for many species in Gondwanan lineages.
Publisher: SAGE Publications
Date: 2006
DOI: 10.1191/0309133306PP469RA
Abstract: Because of the spatiotemporal scales involved and the logistical constraints in collecting landscape-level data, spatially explicit simulation models have become important tools in ecological and biogeographical studies conducted over broad extents. Here we review the methods used and some of the applications of landscape-level models of succession and disturbance dynamics. Mechanistic and stochastic models are compared and contrasted and the development, over the last 15 years, of spatial landscape models of ecological change is discussed. Coarse-grained spatial landscape models are compared with finer-grained in idual-based approaches (eg, forest gap models). Management and monitoring applications of landscape models are considered alongside a discussion of the appropriate use of models in this context. A key area where spatial landscape models of the type described here need to develop is improved integration with the social sciences - both in terms of the parameters and the processes that the models incorporate. Finally issues related to scale and scaling are outlined and, in particular, the utility of methods for linking ecological models operating at disparate scales (eg, forest gap models versus landscape models) is examined.
Publisher: MDPI AG
Date: 10-06-0004
DOI: 10.3390/BIOM11060865
Abstract: Stress contributes to various aspects of malignancy and could influence survival in laryngeal cancer patients. Among antioxidant mechanisms, zinc and the antioxidant enzymes superoxide dismutase 2, catalase and glutathione peroxidase 1 play a major role. The aim of this study was a prospective evaluation of the survival of patients with laryngeal cancer in relation to serum levels of zinc in combination with functional genotype differences of three key antioxidant enzymes. The study group consisted of 300 patients treated surgically for laryngeal cancer. Serum zinc levels and common polymorphisms in SOD2, CAT and GPX1 were analyzed. The risk of death in patients with the lowest zinc levels was increased in comparison with patients with the highest levels. Polymorphisms of antioxidant genes by themselves were not correlated with survival, however, serum zinc level impact on survival was stronger for SOD2 TC/TT and CAT CC variants. GPX1 polymorphisms did not correlate with zinc levels regarding survival. In conclusion, serum zinc concentration appears to be an important prognostic factor for survival of patients diagnosed with laryngeal cancer. When higher zinc levels were correlated with polymorphisms in SOD2 and CAT a further increase in survival was observed.
Publisher: Springer Science and Business Media LLC
Date: 20-11-2022
Publisher: CSIRO Publishing
Date: 2005
DOI: 10.1071/MF04307
Abstract: Digenean parasites of marine bivalves are relatively poorly known, particularly in Australia. We surveyed 2256 bivalve in iduals (47 species, 17 families) from Queensland marine waters incorporating south-east Queensland, Heron Island (southern Great Barrier Reef) and Lizard Island (northern Great Barrier Reef). Infections of trematode species from three families, Bucephalidae, Gorgoderidae and Monorchiidae, were found. Overall prevalence of infection was 2.3%. The Bucephalidae was the most commonly found family 11 species were found in Tellinidae, Ostreidae, Isognomonidae and Spondylidae – the latter two previously unknown as hosts for bucephalids. A single gorgoderid infection was found in a venerid, Lioconcha castrensis. Five species of monorchiids were found from Tellinidae and Lucinidae. All infections are new host arasite records. No infections were found in 35 of the 47 bivalve species s led. The generally low prevalence of infection by digeneans of bivalves suggests that it is unlikely that any of the species reported here are seriously damaging to bivalve populations in these waters. We deduce that, at best, we have some life-cycle information but no actual identifications for 10% of the species of trematodes that infect bivalves of Queensland marine waters.
Publisher: Elsevier BV
Date: 10-2007
Publisher: Wiley
Date: 19-03-2007
DOI: 10.1111/J.1472-4642.2007.00348.X
Abstract: Banksia hookeriana Meissn. (Proteaceae) is a fire‐killed shrub endemic to the northern sandplains of south‐western Australia that could be described as endangered based on its small geographical range ( 5000 km 2 ) and area of occupancy (∼500 km 2 ). Impacts on the species’ geographical range by land clearance for farming and mining, and by altered fire regime, were investigated using three lines of evidence: records of herbarium collections, a comprehensive field survey of extant populations, and air photo and satellite images revealing the recent history of land clearance and fires. These show that the species’ range has contracted by up to 40% in area and 26% latitudinally through the loss of outlier and range limit populations since 1960. In addition, 22% of remaining native shrubland on the Eneabba sandplain has been lost over this period through clearing for farming and mining, representing further habitat loss for B. hookeriana . Detailed investigation of B . hookeriana herbarium collections ( n = 46) revealed important errors that artificially affected the geographical range of the species and emphasized the importance of close examination of all data captured from collection records. Recorded locations occurred hundreds of kilometres outside the current geographical range of the species in areas with different climate and substrate. Incorrect species identification of herbarium specimens further extended the apparent geographical range of the species. On the other hand, credible records indicated the loss of the species from localities at the limits of its range. Overall, a disconcertingly high proportion of records contained errors that may be difficult to identify without close examination of the original collections and detailed ground‐truthing. Were these records to be used to model climate envelopes, identify potential habitat where the species might occur, or might migrate to either as pests or under climate change scenarios, or to analyse evolutionary or ecological theory (for ex le) — as is now becoming commonplace — large errors may ensue.
Publisher: Wiley
Date: 08-2000
Publisher: Elsevier BV
Date: 05-2005
Publisher: Wiley
Date: 07-1998
Publisher: Wiley
Date: 06-1994
Publisher: CSIRO Publishing
Date: 2014
DOI: 10.1071/WF13006
Abstract: Fuel age is an imprecise surrogate for fire hazard in species-rich Mediterranean-type shrublands. We present an efficient method for aerial biomass and litter estimation of shrublands on sandy and calcareous substrates in south-western Australia that enables fuel accumulation patterns to be compared independently of vegetation age. For sites ranging 3–16 years since last fire, total available fuel loads were 2.7–7.6tha–1 for the sandplain and 2.6–8.14tha–1 for the calcareous shrublands. Despite calcareous shrublands having higher soil nutrient concentrations and winter rainfall, total available fuel loads were similar between community types over the range of fuel ages examined. Sandplain biomass was dominated by resprouters and calcareous sites, by non-sprouters. Topographic variation in fuel loads was observed among sandplain sites, with greater available biomass and litter on the deeper sands of dunes compared to swales. More rapid fuel accumulation at the youngest sites and more uniform canopy structure in the calcareous shrublands indicate that they have the potential to support fire at shorter intervals than the sandplain. For each community type, an allometric equation based on the relationship between average maximum plant height and total available fuel was derived that enables rapid estimation of fuel loads that is more accurate than using fuel age.
Publisher: Wiley
Date: 26-07-2014
Publisher: CSIRO Publishing
Date: 2012
DOI: 10.1071/WF11065
Abstract: Fuel age (time since last fire) is often used to approximate fire hazard and informs decisions on placement of shrubland management burns worldwide. However, uncertainty remains concerning the relative importance of fuel age and weather conditions as predictors of fire hazard and behaviour. Using data from 35 experimental burns across three types of shrublands in Western Australia, we evaluated importance of fuel age and fire weather on probability of fire propagation (hazard) and four metrics of fire behaviour (rate of spread, fireline intensity, residence time, surface temperature) under moderate to high fire danger weather conditions. We found significant support for a threshold effect of fuel age for fire propagation but limited evidence for an effect of fuel age or fire weather on rates of spread or fireline intensity, although surface heating and heating duration were significantly related to fuel age and shrubland type. Further analysis suggested that dead fuel mass and accumulation rate rather than live fuels were responsible for this relationship. Using BEHAVE, predicted spread rates and intensities were consistently lower than observed values, suggesting further refinement is needed in modelling shrubland fire behaviour. These data provide important insight into fire behaviour in globally significant, fire-adapted shrublands, informing fire management and relationships between fire frequency and fire intensity.
Publisher: JSTOR
Date: 1992
DOI: 10.2307/2404474
Publisher: Springer Science and Business Media LLC
Date: 1982
DOI: 10.1007/BF00726882
Publisher: Springer Science and Business Media LLC
Date: 30-03-2006
Publisher: Wiley
Date: 08-2009
Publisher: JSTOR
Date: 07-1984
DOI: 10.2307/2845008
Publisher: FapUNIFESP (SciELO)
Date: 04-12-2015
DOI: 10.1590/0001-376520152014-0106
Abstract: Vegetation and soil properties of an iron-rich canga (laterite) island on the largest outcrop of banded-iron formation in Serra de Carajás (eastern Amazonia, Brazil) were studied along a topographic gradient (738-762 m asl), and analyzed to test the hypothesis that soil chemical and physical attributes play a key role in the structure and floristic composition of these plant communities. Soil and vegetation were s led in eight replicate plots within each of the four vegetation types. Surface (0-10 cm) soil s les from each plot were analyzed for basic cations, N, P and plant species density for all species was recorded. CCA ordination analysis showed a strong separation between forest and non-forest sites on the first axis, and between herbaceous and shrubby c o rupestre on the second axis. The four vegetation types shared few plant species, which was attributed to their distinctive soil environments and filtering of their constituent species by chemical, physical and hydrological constraints. Thus, we can infer that Edaphic (pedological) factors are crucial in explaining the types and distributions of c o rupestre vegetation associated with ferruginous ironstone uplands (Canga) in Carajás, eastern Amazonia, therefore the soil properties are the main drivers of vegetation composition and structure on these ironstone islands.
Publisher: Elsevier BV
Date: 06-2018
Publisher: Elsevier BV
Date: 12-2019
DOI: 10.1016/J.TREE.2019.07.009
Abstract: Altered fire regimes resulting from climate change and human activity threaten many terrestrial ecosystems. However, we lack a holistic and detailed understanding of the effects of altering one key fire regime component - season of fire. Altered fire seasonality can strongly affect post-fire recovery of plant populations through interactions with plant phenology. We identify seven key mechanisms of fire seasonality effects under a conceptual demographic framework and review evidence for these. We reveal negative impacts of altered fire seasonality and identify research gaps for mechanisms and climate types for future analyses of fire seasonality effects within the identified demographic framework. This framework and these mechanisms can inform critical decisions for conservation, land management, and fire management policy development globally.
Publisher: Springer Science and Business Media LLC
Date: 16-09-2011
Publisher: Wiley
Date: 04-1972
Abstract: Selection bias occurs when recruiters selectively enrol patients into the trial based on what the next treatment allocation is likely to be. This can occur even if appropriate allocation concealment is used if recruiters can guess the next treatment assignment with some degree of accuracy. This typically occurs in unblinded trials when restricted randomisation is implemented to force the number of patients in each arm or within each centre to be the same. Several methods to reduce the risk of selection bias have been suggested however, it is unclear how often these techniques are used in practice. We performed a review of published trials which were not blinded to assess whether they utilised methods for reducing the risk of selection bias. We assessed the following techniques: (a) blinding of recruiters (b) use of simple randomisation (c) avoidance of stratification by site when restricted randomisation is used (d) avoidance of permuted blocks if stratification by site is used and (e) incorporation of prognostic covariates into the randomisation procedure when restricted randomisation is used. We included parallel group, in idually randomised phase III trials published in four general medical journals (BMJ, Journal of the American Medical Association, The Lancet, and New England Journal of Medicine) in 2010. We identified 152 eligible trials. Most trials (98%) provided no information on whether recruiters were blind to previous treatment allocations. Only 3% of trials used simple randomisation 63% used some form of restricted randomisation, and 35% did not state the method of randomisation. Overall, 44% of trials were stratified by site of recruitment 27% were not, and 29% did not report this information. Most trials that did stratify by site of recruitment used permuted blocks (58%), and only 15% reported using random block sizes. Many trials that used restricted randomisation also included prognostic covariates in the randomisation procedure (56%). The risk of selection bias could not be ascertained for most trials due to poor reporting. Many trials which did provide details on the randomisation procedure were at risk of selection bias due to a poorly chosen randomisation methods. Techniques to reduce the risk of selection bias should be more widely implemented.
Publisher: Wiley
Date: 08-2009
Publisher: Informa UK Limited
Date: 06-1995
Publisher: Springer Science and Business Media LLC
Date: 11-08-2023
DOI: 10.1186/S42408-023-00205-3
Abstract: In recent decades, fire has increasingly occurred in the tropical montane rainforests of northern Vietnam. However, there are few studies of the effects of fire on forest composition and recovery in this region, and understanding these effects is critical for effective forest fire management and conservation. Forest plant species richness, structure (density, basal area), and composition were quantified for 133 forest plots randomly located in unburned ( 20 years since last fire) and recently burned (3–9 years since fire) vegetation associated with ten selected wildfires in three provinces of northern Vietnam where fires since 2000 were most frequent. Linear mixed effect models and nonmetric multidimensional scaling (NMDS) ordination were used to explore the structure, richness, and composition of burned and unburned forests and their environmental drivers, and to explore the key drivers of regeneration patterns in burned forest, including time since fire occurrence, fire severity, and distance to unburned forest edge. Total species richness and ersity, tree species richness, tree density, and basal area were higher in unburned (vs. burned) forest plots, low (vs. high) severity burn areas, near (vs. far) from the closest unburned forest edge, and longer (vs. shorter) time since last fire. Results suggest that while burned forests were recovering on a trajectory back towards unburned forest composition, recovery was likely to be markedly slowed where fires were large (distance from edge effects) and/or of high severity, and forests may shift towards a different state (i.e., composition and structure) where more than one fire affects the same area over short time intervals. This study provides insights into the effects of fire and other environmental factors on forest composition and recovery in the tropical montane forests of northern Vietnam, crucial for informing policymakers involved in forest conservation and management.
Publisher: Public Library of Science (PLoS)
Date: 29-05-2013
Publisher: Oxford University Press (OUP)
Date: 19-07-2010
DOI: 10.1093/AOB/MCQ140
Publisher: Springer Science and Business Media LLC
Date: 19-01-2017
DOI: 10.1038/BJC.2016.426
Publisher: Oxford University Press (OUP)
Date: 09-10-2017
DOI: 10.1093/IJE/DYX131
Publisher: Wiley
Date: 12-1978
Publisher: Springer Science and Business Media LLC
Date: 27-11-2013
Publisher: Wiley
Date: 12-1998
Publisher: CSIRO Publishing
Date: 2023
DOI: 10.1071/BT22134
Publisher: Oxford University Press (OUP)
Date: 25-11-2017
DOI: 10.1093/IJE/DYX236
Publisher: Wiley
Date: 12-1991
Publisher: Springer Science and Business Media LLC
Date: 10-1991
DOI: 10.1007/BF02858770
Publisher: Springer Science and Business Media LLC
Date: 07-10-2011
Publisher: Public Library of Science (PLoS)
Date: 04-10-2018
Publisher: Elsevier BV
Date: 10-2020
Publisher: Springer Science and Business Media LLC
Date: 1995
DOI: 10.1007/BF00365565
Publisher: Wiley
Date: 28-03-2011
Publisher: Wiley
Date: 06-06-2013
Publisher: Elsevier BV
Date: 11-2015
DOI: 10.1016/J.SCITOTENV.2015.04.002
Abstract: Postfire resprouting and recruitment from seed are key plant life-history traits that influence population dynamics, community composition and ecosystem function. Species can have one or both of these mechanisms. They confer resilience, which may determine community composition through differential species persistence after fire. To predict ecosystem level responses to changes in climate and fire conditions, we examined the proportions of these plant fire-adaptive traits among woody growth forms of 2880 taxa, in eight fire-prone ecosystems comprising ~87% of Australia's land area. Shrubs comprised 64% of the taxa. More tree (>84%) than shrub (~50%) taxa resprouted. Basal, epicormic and apical resprouting occurred in 71%, 22% and 3% of the taxa, respectively. Most rainforest taxa (91%) were basal resprouters. Many trees (59%) in frequently-burnt eucalypt forest and savanna resprouted epicormically. Although crown fire killed many mallee (62%) and heathland (48%) taxa, fire-cued seeding was common in these systems. Postfire seeding was uncommon in rainforest and in arid Acacia communities that burnt infrequently at low intensity. Resprouting was positively associated with ecosystem productivity, but resprouting type (e.g. basal or epicormic) was associated with local scale fire activity, especially fire frequency. Although rainforest trees can resprout they cannot recruit after intense fires and may decline under future fires. Semi-arid Acacia communities would be susceptible to increasing fire frequencies because they contain few postfire seeders. Ecosystems dominated by obligate seeders (mallee, heath) are also susceptible because predicted shorter inter-fire intervals will prevent seed bank accumulation. Savanna may be resilient to future fires because of the adaptive advantage of epicormic resprouting among the eucalypts. The substantial non-resprouting shrub component of shrublands may decline, but resilient Eucalyptus spp. will continue to dominate under future fire regimes. These patterns of resprouting and postfire seeding provide new insights to ecosystem assembly, resilience and vulnerability to changing fire regimes on this fire-prone continent.
Publisher: Wiley
Date: 28-06-2008
Publisher: Wiley
Date: 28-07-2006
Publisher: Springer Science and Business Media LLC
Date: 12-11-2014
Publisher: Springer Science and Business Media LLC
Date: 06-09-2019
DOI: 10.1038/S41380-019-0463-8
Abstract: Based on the discovery by the Resilience Project (Chen R. et al. Nat Biotechnol 34:531–538, 2016) of rare variants that confer resistance to Mendelian disease, and protective alleles for some complex diseases, we posited the existence of genetic variants that promote resilience to highly heritable polygenic disorders1,0 such as schizophrenia. Resilience has been traditionally viewed as a psychological construct, although our use of the term resilience refers to a different construct that directly relates to the Resilience Project, namely: heritable variation that promotes resistance to disease by reducing the penetrance of risk loci, wherein resilience and risk loci operate orthogonal to one another. In this study, we established a procedure to identify unaffected in iduals with relatively high polygenic risk for schizophrenia, and contrasted them with risk-matched schizophrenia cases to generate the first known “polygenic resilience score” that represents the additive contributions to SZ resistance by variants that are distinct from risk loci. The resilience score was derived from data compiled by the Psychiatric Genomics Consortium, and replicated in three independent s les. This work establishes a generalizable framework for finding resilience variants for any complex, heritable disorder.
Publisher: Wiley
Date: 28-04-2010
Publisher: Wiley
Date: 03-1982
Publisher: CSIRO Publishing
Date: 1998
DOI: 10.1071/BT97041
Abstract: Leucospermum conocarpodendron (L.) Beuk. and Mimetes fimbriifolius Salisb. ex J.Knight co-occur in the southern Cape Peninsula, where we studied their distribution patterns, demography and fire responses. Leucospermum conocarpodendron has relatively larger seedlings and is therefore the likely competitive dominant. Adults and seedlings of both species are widely spaced and interspecific competition is unlikely to cause competitive exclusion. Differences between the two species in recruitment levels and fire-mortality are small. Thus their size-class distributions are very similar. They are restricted to shallow-soil rocky habitats, not only because of reduced fire intensity in these sites, but because these are habitats avoided by the faster growing more competitive reseeding Proteaceae. Co-existence of these two species appears to mainly be due to fire keeping populations sparse, and ants keeping in iduals fairly isolated.
Publisher: Elsevier BV
Date: 02-2017
Publisher: Wiley
Date: 21-08-2006
Publisher: Elsevier BV
Date: 02-2019
DOI: 10.1016/J.CCELL.2018.12.011
Abstract: Biallelic germline mutations affecting NTHL1 predispose carriers to adenomatous polyposis and colorectal cancer, but the complete phenotype is unknown. We describe 29 in iduals carrying biallelic germline NTHL1 mutations from 17 families, of which 26 developed one (n = 10) or multiple (n = 16) malignancies in 14 different tissues. An unexpected high breast cancer incidence was observed in female carriers (60%). Mutational signature analysis of 14 tumors from 7 organs revealed that NTHL1 deficiency underlies the main mutational process in all but one of the tumors (93%). These results reveal NTHL1 as a multi-tumor predisposition gene with a high lifetime risk for extracolonic cancers and a typical mutational signature observed across tumor types, which can assist in the recognition of this syndrome.
Publisher: Elsevier BV
Date: 02-2012
Publisher: Springer Science and Business Media LLC
Date: 18-06-2018
Publisher: Springer Science and Business Media LLC
Date: 06-10-2013
Publisher: Hindawi Limited
Date: 12-03-2018
DOI: 10.1002/HUMU.23406
Publisher: Wiley
Date: 16-08-2020
Publisher: Elsevier BV
Date: 11-2007
DOI: 10.2111/06-143R1.1
Publisher: Wiley
Date: 03-1982
Publisher: Elsevier BV
Date: 05-2022
Publisher: Wiley
Date: 03-1987
Publisher: Wiley
Date: 10-2008
Publisher: Springer Science and Business Media LLC
Date: 30-05-2015
Publisher: MDPI AG
Date: 28-08-2021
DOI: 10.3390/BIOMEDICINES9091105
Abstract: In following study we examined whether blood arsenic (As) levels combined with specific polymorphisms in MT1B, GSTP1, ABCB1, NQO1, CRTC3, GPX1, SOD2, CAT, XRCC1, ERCC2 can be used as a marker for the detection of colorectal cancer (CRC) among Polish women. A retrospective case-control study of CRC included 83 CRC cases and 78 healthy controls. From each study participant pre-treatment peripheral blood was collected for As level measurement by inductively coupled–plasma mass spectrometry (ICP-MS). We estimated the odds ratio (OR) of the association between blood-As levels and CRC using multivariable unconditional logistic regression models. A low blood-As level (0.27–0.67 µg/L) was associated with an increased frequency of CRC (OR: 3.69 p = 0.005). This correlation was significantly greater when participants carried particular gene variants: CAT, rs1001179-nonCC (OR: 19.4 p = 0.001) ABCB1 rs2032582–CC (OR: 14.8 p = 0.024) GPX1 rs1050450-CC (OR: 11.6 p = 0.002) and CRTC3 rs12915189-nonGG (OR: 10.3 p = 0.003). Our study provides strong evidence that low blood-As levels are significantly associated with increased CRC occurrence and that particular gene variants significantly enhanced this correlation however, due to the novelty of these findings, we suggest further validation before a definitive statement that the combined effect of low blood-As levels with specific gene polymorphisms is a suitable CRC biomarker.
Publisher: Wiley
Date: 21-09-2014
DOI: 10.1002/CJP2.109
Publisher: Springer Science and Business Media LLC
Date: 05-06-2017
Publisher: CSIRO Publishing
Date: 2007
DOI: 10.1071/BT06024
Abstract: We have studied the ecology and conservation requirements of Banksia species in the species-rich sandplains of south-western Australia for 25 years. Loss of habitat through land-clearing has had the greatest impact on their conservation status over the last 50 years. Ascertaining optimal conditions for conservation management in bushland requires detailed knowledge of the species under consideration, including demographic attributes, fire regime, growing conditions and interactions with other species. Where populations have been fragmented, seed production per plant has also fallen. The group most vulnerable to the vagaries of fire, disease, pests, weeds and climate change are the non-sprouters, rather than the resprouters, with population extinction so far confined to non-sprouting species. Recent short-interval fires ( years) appear to have had little impact at the landscape scale, possibly because they are rare and patchy. Fire intervals exceeding 25–50 years can also lead to local extinction. Up to 200 viable seeds are required for parent replacement in Banksia hookeriana when growing conditions are poor (low post-fire rainfall, commercial flower harvesting) and seed banks of this size can take up to 12 years to be reached. Seed production is rarely limited by pollinators, but interannual seasonal effects and resource availability are important. Genetic ersity of the seed store is quickly restored to the level of the parents in B. hookeriana. Florivores and granivores generally reduce seed stores, although this varies markedly among species. In Banksia tricuspis, black cockatoos actually increase seed set by selectively destroying borers. Potential loss of populations through the root pathogen Phytophthora cinnamomi also challenges management, especially in the southern sandplains. Prefire dead plants are a poor source of seeds for the next generation when fire does occur. Harvesting seeds and sowing post-fire have much to commend them for critically endangered species. Bare areas caused by humans can result in ideal conditions for plant growth and seed set. However, in the case of B. hookeriana/B. prionotes, disturbance by humans has fostered hybridisation, threatening the genetic integrity of both species, whereas fine-textured soils are unsuitable for colonisation or rehabilitation. Few viable seeds become seedlings after fire, owing to post-release granivory and herbivory and unsuitable germination conditions. Seedling-competitive effects ensure that season/intensity of fire is not critical to recruitment levels, except in the presence of weeds. Water availability during summer–autumn is critical and poses a problem for conservation management if the trend for declining rainfall in the region continues. Our simulation modelling for three banksias shows that the probability of co-occurrence is maximal when fire is stochastic around a mean of 13 years, and where fire-proneness and post-fire recruitment success vary in the landscape. Modelling results suggest that non-sprouting banksias could not survive the pre-European frequent-fire scenario suggested by the new grasstree technique for south-western Australia. However, we have yet to fully explore the conservation significance of long-distance dispersal of seeds, recently shown to exceed 2.5 km in B. hookeriana.
Publisher: Informa UK Limited
Date: 12-1988
Publisher: Informa UK Limited
Date: 12-1988
Publisher: Elsevier BV
Date: 07-2002
Publisher: Wiley
Date: 29-01-2008
DOI: 10.3170/2008-8-18401
Publisher: Wiley
Date: 27-09-2012
Publisher: Wiley
Date: 08-06-2020
Publisher: Wiley
Date: 12-1998
Publisher: Elsevier BV
Date: 10-2009
Publisher: American Association for Cancer Research (AACR)
Date: 31-05-2017
DOI: 10.1158/0008-5472.CAN-16-2568
Abstract: Breast cancer risks conferred by many germline missense variants in the BRCA1 and BRCA2 genes, often referred to as variants of uncertain significance (VUS), have not been established. In this study, associations between 19 BRCA1 and 33 BRCA2 missense substitution variants and breast cancer risk were investigated through a breast cancer case–control study using genotyping data from 38 studies of predominantly European ancestry (41,890 cases and 41,607 controls) and nine studies of Asian ancestry (6,269 cases and 6,624 controls). The BRCA2 c.9104A& C, p.Tyr3035Ser (OR = 2.52 P = 0.04), and BRCA1 c.5096G& A, p.Arg1699Gln (OR = 4.29 P = 0.009) variant were associated with moderately increased risks of breast cancer among Europeans, whereas BRCA2 c.7522G& A, p.Gly2508Ser (OR = 2.68 P = 0.004), and c.8187G& T, p.Lys2729Asn (OR = 1.4 P = 0.004) were associated with moderate and low risks of breast cancer among Asians. Functional characterization of the BRCA2 variants using four quantitative assays showed reduced BRCA2 activity for p.Tyr3035Ser compared with wild-type. Overall, our results show how BRCA2 missense variants that influence protein function can confer clinically relevant, moderately increased risks of breast cancer, with potential implications for risk management guidelines in women with these specific variants. Cancer Res 77(11) 2789–99. ©2017 AACR.
Publisher: Wiley
Date: 23-02-2019
DOI: 10.1002/AJMG.B.32716
Publisher: Elsevier BV
Date: 03-2018
Publisher: Wiley
Date: 25-04-2021
DOI: 10.1111/REC.13379
Abstract: Ecological resilience is widely acknowledged as a vital attribute of successful ecosystem restoration, with potential for restoration practice to contribute to this goal. Hence, defining common metrics of resilience to naturally occurring disturbances is essential for restoration planning, efforts, and monitoring. Here, we reviewed how plant community ecologists have measured resilience of restoration projects to disturbances and propose a framework to guide measurement of restoration projects to disturbance. We found 22 studies that investigated the impact of disturbances on restoration projects, from three continents and for three disturbance types. Over half of the studies were from Australia, with the dataset biased toward fire responses of restored, or partially restored, forest ecosystems. Native plant species richness, cover, and density were common response variables. Studies varied in restoration context, design, response variables, and statistical approaches, limiting generalizations. Nonetheless we have identified several response variables that offer potential as lagging indicators (e.g. species richness) and leading indicators (e.g. recruitment) of resilience in erse vegetation types exposed to a variety of disturbance regimes. We suggest a third set of variables, proxy measures of resilience (e.g. functional redundancy), to complement lagging and leading indicators. We conclude with a framework to guide decisions about when to use each of the three types of measures to assess resilience of restoration projects to disturbance, providing some clarity to decision‐making despite the uncertainty of changing disturbance regimes. Lastly, we invite researchers to understand the impact of disturbance on the resilience of restoration projects, rather than assume resilience.
Publisher: Wiley
Date: 03-1985
Publisher: Springer Science and Business Media LLC
Date: 06-1997
DOI: 10.1007/BF02201856
Abstract: The aim of this study was to assess vaccination perception and the prevalence of the overall vaccination coverage (VC) and associated factors among university students. An online study was conducted among students of a university in Rouen (Normandy), France, in January 2021, with questions about the VC and perception of the vaccines. The convenience s le included 3089 students (response rate of 10.3%), with a mean age of 20.3 (SD = 1.9). The overall VC was 27.8% (39.2% for the healthcare students (HCS) and 21.3% for the non-HCS
Publisher: Wiley
Date: 27-09-2002
Publisher: Springer Science and Business Media LLC
Date: 16-12-2020
Publisher: Elsevier BV
Date: 09-2011
Publisher: Springer Science and Business Media LLC
Date: 11-07-2015
Publisher: Elsevier BV
Date: 05-2008
Publisher: Wiley
Date: 24-02-1999
DOI: 10.2307/3237304
Publisher: Wiley
Date: 18-06-2003
DOI: 10.1046/J.1420-9101.2003.00548.X
Abstract: Putative hybrids between Banksia hookeriana and B. prionotes were identified among 12 of 106 populations of B. hookeriana located at or near anthropogenically disturbed sites, mainly roadways, but none in 156 undisturbed populations. Morphometrics and AFLP markers confirmed that a hybrid swarm existed in a selected disturbed habitat, whereas no intermediates were present where the two species co-occurred in undisturbed vegetation. In iduals of both species in disturbed habitats at 12 sites were more vigorous, with greater size and more flower heads than their counterparts in undisturbed vegetation. These more fecund plants also showed a shift in season and duration of flowering. By promoting earlier flowering of B. hookeriana plants and prolonging flowering of B. prionotes, anthropogenic disturbance broke the phenological barrier between these two species. We conclude that anthropogenic disturbance promotes hybridization through increasing opportunities for gene flow by reducing interpopulation separation, increasing gamete production and, especially, promoting coflowering.
Publisher: Wiley
Date: 09-2014
Publisher: Wiley
Date: 03-1982
Publisher: Wiley
Date: 29-12-2011
Publisher: Informa UK Limited
Date: 2003
Publisher: Wiley
Date: 30-10-2012
DOI: 10.1111/NPH.12001
Abstract: Resprouting as a response to disturbance is now widely recognized as a key functional trait among woody plants and as the basis for the persistence niche. However, the underlying mechanisms that define resprouting responses to disturbance are poorly conceptualized. Resprouting ability is constrained by the interaction of the disturbance regime that depletes the buds and resources needed to fund resprouting, and the environment that drives growth and resource allocation. We develop a b uds‐ p rotection‐ r esources ( BPR ) framework for understanding resprouting in fire‐prone ecosystems, based on bud bank location, bud protection, and how buds are resourced. Using this framework we go beyond earlier emphases on basal resprouting and highlight the importance of apical, epicormic and below‐ground resprouting to the persistence niche. The BPR framework provides insights into: resprouting typologies that include both fire resisters (i.e. survive fire but do not resprout) and fire resprouters the methods by which buds escape fire effects, such as thick bark and the predictability of community assembly of resprouting types in relation to site productivity, disturbance regime and competition. Furthermore, predicting the consequences of global change is enhanced by the BPR framework because it potentially forecasts the retention or loss of above‐ground biomass. Contents Summary 19 I. Introduction 20 II. Resprouters rather than ‘sprouters’ 21 III. How do plants resprout? 21 IV. Life‐history consequences of resprouting 27 V. Environmental constraints on resprouting 28 VI. Resprouting, community patterns and assembly 29 VII. Global change, carbon storage and resprouting 30 VIII. Conclusions 31 Acknowledgements 31 References 32
Publisher: Wiley
Date: 13-01-2010
Publisher: Wiley
Date: 27-08-2009
Publisher: Springer Science and Business Media LLC
Date: 19-02-2022
Publisher: Wiley
Date: 19-11-2008
DOI: 10.1111/J.1469-8137.2008.02686.X
Abstract: Estimating distances and rates of seed dispersal, especially long-distance dispersal (LDD), is critical for understanding the dynamics of patchily distributed populations and species' range shifts in response to environmental change. Daviesia triflora (Papilionaceae) is an ant-dispersed shrub. The ant Rhytidoponera violacea was recorded dispersing its seeds to a maximum distance of 4.7 m, and in more intensive trials seeds of a related species from the study area, to a maximum of 8.1 m. Microsatellite DNA markers and population assignment tests identified interpopulation immigrants among 764 plants on 23 adjacent dunes bearing D. triflora, and 13 interpopulation seed dispersal (LDD) events (1.7%) were inferred. The distance between source and sink populations ranged from 410 m to 2350 m (mean 1260 m). These distances exceed ant dispersal distances by two to three orders of magnitude but are comparable with previous measurements of LDD for two co-occurring wing-seeded (wind-dispersed) species from the same system. The observed distances of seed dispersal in this arillate species demonstrate the significance of nonstandard dispersal mechanisms in LDD and the independence of these from primary dispersal syndromes. The likely role of emus in dispersal of the many 'ant-dispersed' species in Australia is discussed.
Publisher: Elsevier BV
Date: 06-2001
Publisher: Springer Science and Business Media LLC
Date: 11-06-2018
Publisher: Springer Science and Business Media LLC
Date: 24-06-2010
Publisher: Informa UK Limited
Date: 10-1993
Publisher: Wiley
Date: 27-02-2004
Publisher: Wiley
Date: 12-02-2015
DOI: 10.1111/AVSC.12162
Publisher: CSIRO Publishing
Date: 2004
DOI: 10.1071/PC040009
Abstract: Natural communities have the capacity to regenerate themselves, and this functional ecosystem attribute must be regarded as a key indicator of success for revegetation programmes. The accumulation of species (and in iduals) as dormant propagules in a soil seedbank, representing potential future states for the vegetation, is one possible index of revegetation success. Here, we investigate the soil seedbanks for five natural vegetation (Box-Ironbark forest) remnants, a topsoil stockpile and three revegetated mine-site areas associated with gold mining at Stawell (Victoria, Australia). The revegetation efforts largely date from 1987 and, in terms of their composition and structure, are relatively similar to natural vegetation remnants. Soil s les were treated with heat or smoke (plus control) and were monitored for seedling emergence, species composition and density in the glasshouse for 150 days. Seedling densities in treated seedbank s les were high (2 200 to 17 500 seedlings m-2) while species richness was low, ranging from 10 to 20 species per s le. Exotic species made up 22?61 % of emergents and 33?50% of species observed. Correlation of seedbank composition and density with chemical attributes of soils, and with above ground (extant) vegetation at sites showed few significant relationships. Total species richness and the proportion of exotic species varied significantly between natural bushland remnants and revegetation areas. Richness was highest, and the proportion of exotic species was lowest in natural bushland s les. Total emergent numbers and the density of exotic emergents did not vary significantly between remnant bushland and revegetation areas. Declining vigour of some woody species in revegetation sites that are well represented in the seedbank, including Acacia pycnantha and A. genistifolia, indicates that the reintroduction of fire might be an appropriate management practice to facilitate long-term recovery of a functional community on these revegetated surfaces, but the potential for the establishment of weed species from the seed-bank following fire may pose a challenge to management.
Publisher: Wiley
Date: 04-2000
Publisher: Public Library of Science (PLoS)
Date: 23-07-2018
Publisher: SAGE Publications
Date: 09-2001
Abstract: This paper begins to identify the relative roles of climiiate change, people and fire as factors in the late-Pleistocene and Holocene evolution of one of the most erse terrestrial ecosystems in southern Australia. Our research illustrates that pollen from mediterranean-type heathlands can be recognized from sediments taken from small basins in semi-arid ecosystems. The use of pollen and carbonized particle analyses from sedimenitcores, in conjunction with ecological research on planit-fire relationships, establishes a role for palaeoecological techniques in the interpretationi of long-term processes in semi-arid heathlands in Australia. Radiocarbon dates indicate that the treeless structure at our study site in the Little Desert of western Victoria has existed since at least the early Holocene. Pollen evidence indicates an increase in plant ersity, especially in Proteaceae and fire ephemerals, and a decrease in fire-sensitive taxa (e.g.. Callitris spp., Allocasuarina muelleriana type) our the last 4000 years. This decline octirs in conjunction with increases in the frequency of carbonized particles.
Publisher: JSTOR
Date: 02-1996
DOI: 10.2307/2261695
Publisher: JSTOR
Date: 03-1990
DOI: 10.2307/2845327
Publisher: Wiley
Date: 09-1985
Publisher: Wiley
Date: 1999
Publisher: Wiley
Date: 16-09-2016
Publisher: Springer Science and Business Media LLC
Date: 11-06-2018
DOI: 10.1038/S41467-018-04109-8
Abstract: Prostate cancer is a polygenic disease with a large heritable component. A number of common, low-penetrance prostate cancer risk loci have been identified through GWAS. Here we apply the Bayesian multivariate variable selection algorithm JAM to fine-map 84 prostate cancer susceptibility loci, using summary data from a large European ancestry meta-analysis. We observe evidence for multiple independent signals at 12 regions and 99 risk signals overall. Only 15 original GWAS tag SNPs remain among the catalogue of candidate variants identified the remainder are replaced by more likely candidates. Biological annotation of our credible set of variants indicates significant enrichment within promoter and enhancer elements, and transcription factor-binding sites, including AR, ERG and FOXA1. In 40 regions at least one variant is colocalised with an eQTL in prostate cancer tissue. The refined set of candidate variants substantially increase the proportion of familial relative risk explained by these known susceptibility regions, which highlights the importance of fine-mapping studies and has implications for clinical risk profiling.
Publisher: Informa UK Limited
Date: 04-1988
Publisher: Wiley
Date: 09-2002
Publisher: Wiley
Date: 06-1999
Publisher: Wiley
Date: 11-08-2021
DOI: 10.1002/EAP.2411
Abstract: Unseasonal fire occurrence is increasing globally, driven by climate change and other human activity. Changed timing of fire can inhibit postfire seedling recruitment through interactions with plant phenology (the timing of key processes, e.g., flower initiation, seed production, dispersal, germination), and therefore threaten the persistence of many plant species. Although empirical evidence from winter‐rainfall ecosystems shows that optimal seedling recruitment is expected following summer and autumn (dry season) fires, we sought experimental evidence isolating the mechanisms of poor recruitment following unseasonal (wet season) fire. We implemented a seed‐sowing experiment using nine species native to fire‐prone, Mediterranean‐climate woodlands in southwestern Australia to emulate the timing of postfire recruitment and test key mechanisms of fire seasonality effects. For seeds sown during months when fire is unseasonal (i.e., August–September: end of the wet winter season), seedling recruitment was reduced by up to 99% relative to seeds sown during seasonal fire months (i.e., May–June: end of the dry summer season) because of varying seed persistence, seedling emergence, and seedling survival. We found that up to 70 times more seedlings emerged when seeds were sown during seasonal fire months compared to when seeds were sown during unseasonal fire months. The few seedlings that emerged from unseasonal sowings all died with the onset of the dry season. Of the seeds that failed to germinate from unseasonal sowings, only 2% survived exposure on the soil surface over the ensuing hot and dry summer. Our experimental results demonstrate the potential for unseasonal fire to inhibit seedling recruitment via impacts on pregermination seed persistence and seedling establishment. As ongoing climate change lengthens fire seasons (i.e., unseasonal wildfires become more common) and managed fires are implemented further outside historically typical fire seasons, postfire seedling recruitment may become more vulnerable to failure, causing shifts in plant community composition towards those with fewer species solely dependent on seeds for regeneration.
Publisher: Elsevier BV
Date: 02-2015
Publisher: JSTOR
Date: 07-1988
DOI: 10.2307/2845442
Publisher: Wiley
Date: 03-1993
DOI: 10.2307/1939311
Publisher: Wiley
Date: 12-2001
Publisher: Springer Science and Business Media LLC
Date: 12-1995
DOI: 10.1007/BF01245387
Publisher: Public Library of Science (PLoS)
Date: 06-07-2018
Publisher: Springer Science and Business Media LLC
Date: 23-05-2022
DOI: 10.1007/S11258-022-01244-7
Abstract: Climate change projections predict that Mediterranean-type ecosystems (MTEs) are becoming hotter and drier and that fires will become more frequent and severe. While most plant species in these important bio ersity hotspots are adapted to hot, dry summers and recurrent fire, the Interval Squeeze framework suggests that reduced seed production (demographic shift), reduced seedling establishment after fire (post fire recruitment shift), and reduction in the time between successive fires (fire interval shift) will threaten fire killed species under climate change. One additional potential driver of accelerated species decline, however, has not been considered so far: the decrease in pollination success observed in many ecosystems worldwide has the potential to further reduce seed accumulation and thus population persistence also in these already threatened systems. Using the well-studied fire-killed and serotinous shrub species Banksia hookeriana as an ex le, we apply a new spatially implicit population simulation model to explore population dynamics under past (1988–2002) and current (2003–2017) climate conditions, deterministic and stochastic fire regimes, and alternative scenarios of pollination decline. Overall, model results suggest that while B. hookeriana populations were stable under past climate conditions, they will not continue to persist under current (and prospective future) climate. Negative effects of climatic changes and more frequent fires are reinforced by the measured decline in seed set leading to further reduction in the mean persistence time by 12–17%. These findings clearly indicate that declining pollination rates can be a critical factor that increases further the pressure on the persistence of fire-killed plants. Future research needs to investigate whether other fire-killed species are similarly threatened, and if local population extinction may be compensated by recolonization events, facilitating persistence in spatially structured meta-communities.
Publisher: Wiley
Date: 2023
DOI: 10.1111/AVSC.12713
Abstract: Responses of ecological restoration projects to disturbances are rarely explored, yet their capacity to withstand and recover from disturbance (resilience) is a critical measure of restoration success. In many plant communities, the soil seed bank (SSB) provides an important source of propagules for species persistence and community resilience to disturbance. Understanding how SSBs develop with time can inform restoration of resilient ecosystems. Here, in fire‐prone Banksia woodland restoration following sand mining, we ask: (a) how does the smoke‐responsive (dormancy broken by smoke) SSB develop over time (b) what plant‐trait and climate factors influence its development and (c) what do the data suggest for the resilience of these restored woodlands to fire? Ellenbrook, Swan Coastal Plain, Western Australia (latitude −31.76, longitude 115.95). We used smoke, a key germination cue associated with fire disturbance, to trigger germination of the SSB in Banksia woodland restoration. Using a chronosequence of nine ages between 3 and 26 years since initiation of restoration, we tested how the SSB develops using counts and richness of germinating native and invasive annuals, and native perennial obligate seeding and resprouting species. To understand the contribution of above‐ground restored vegetation to SSB development, we compared Sørensen's similarity of the smoke germinable SSB (smoked SSB) and untreated germinable SSB (control SSB) with above‐ground vegetation. Smoked SSB germinant density decreased with restoration age for both native and invasive annuals, but was stable for native perennials. Similarity between smoked SSB and above‐ground vegetation was higher for perennial obligate seeders than for resprouters and peaked for perennials at 23 years. Post‐fire regeneration potential of the SSB was evident across the chronosequence, with restoration age influencing the density of native annuals and overall composition of the SSB. The findings for perennial species suggest an increase in resilience to fire with restoration age.
Publisher: Wiley
Date: 12-1998
Publisher: Springer Science and Business Media LLC
Date: 05-10-2010
Publisher: Elsevier BV
Date: 09-2018
Publisher: The Royal Society
Date: 11-2016
DOI: 10.1098/RSOS.160637
Abstract: Declining rainfall is projected to have negative impacts on the demographic performance of plant species. Little is known about the adaptive capacity of species to respond to drying climates, and whether adaptation can keep pace with climate change. In fire-prone ecosystems, episodic recruitment of perennial plant species in the first year post-fire imposes a specific selection environment, offering a unique opportunity to quantify the scope for adaptive response to climate change. We examined the growth of seedlings of four fire-killed species under control and drought conditions for seeds from populations established in years following fire receiving average-to-above-average winter rainfall, or well-below-average winter rainfall. We show that offspring of plants that had established under drought had more efficient water uptake, and/or stored more water per unit biomass, or developed denser leaves, and all maintained higher survival in simulated drought than did offspring of plants established in average annual rainfall years. Adaptive phenotypic responses were not consistent across all traits and species, while plants that had established under severe drought or established in years with average-to-above-average rainfall had an overall different physiological response when growing either with or without water constraints. Seedlings descended from plants established under severe drought also had elevated gene expression in key pathways relating to stress response. Our results demonstrate the capacity for rapid adaptation to climate change through phenotypic variation and regulation of gene expression. However, effective and rapid adaptation to climate change may vary among species depending on their capacity to maintain robust populations under multiple stresses.
Publisher: Springer Science and Business Media LLC
Date: 20-03-2018
Publisher: Wiley
Date: 03-1997
Publisher: Informa UK Limited
Date: 1992
Publisher: Informa UK Limited
Date: 1992
Publisher: Wiley
Date: 07-2003
Publisher: Wiley
Date: 09-04-2003
Publisher: Hindawi Limited
Date: 06-04-2018
DOI: 10.1002/HUMU.23411
Publisher: Springer Science and Business Media LLC
Date: 23-10-2017
DOI: 10.1038/NATURE24284
Publisher: Wiley
Date: 28-01-2009
Publisher: Elsevier BV
Date: 2010
Publisher: CSIRO Publishing
Date: 2010
DOI: 10.1071/BT10013
Abstract: Functional-trait analysis at a global scale has found evidence for evolutionary specialisation of species into those designed to acquire resources rapidly and those designed to conserve resources. The present study aimed to determine whether such a trade-off exists in sclerophyllous vegetation in Australia. We measured 10 traits for 167 plant species. The first axis of a principal components analysis represented a trade-off between resource acquisition and resource conservation, consistent with global trends. Common traits shared by resource-conservative species included low specific leaf area (SLA), resprouting, ant-dispersal, and ericoid mycorrhizal and ectomycorrhizal associations. These attributes were typical of 3 of 13 functional groups produced by cluster analysis (eucalypts, ant-dispersed shrubs, ericoid heaths) that had the lowest SLA, and were almost exclusively native shrubs and trees. Resource-acquisitive species had high SLA, a small stature, annual life cycle, arbuscular mycorrhizal or non-mycorrhizal associations, and small, wind-dispersed seeds. These attributes are similar to those identified for species with a ruderal strategy and were typical of the functional groups representing wind-dispersed composites, AM annuals and non-mycorrhizal annuals that had the highest SLA and were dominated by introduced species. Comparable trait associations have been found in other studies, suggesting that similar processes drive plant design at a global scale. However, there were some patterns specific to the flora studied that were attributable to adaptations to suit the nutrient-poor soils and arid conditions typical of the Australian environment.
Publisher: Informa UK Limited
Date: 03-2015
DOI: 10.1071/MU13113
Publisher: Wiley
Date: 14-03-2006
Publisher: Springer Science and Business Media LLC
Date: 2018
DOI: 10.1038/BJC.2017.429
Publisher: Springer Science and Business Media LLC
Date: 1999
Publisher: Springer Science and Business Media LLC
Date: 14-03-2020
Publisher: Wiley
Date: 06-2015
DOI: 10.1890/140231
Publisher: Wiley
Date: 09-12-2016
DOI: 10.1111/OIK.03680
Publisher: MDPI AG
Date: 05-08-2021
DOI: 10.3390/BIOM11081160
Abstract: The effects of heavy metals on cancer risk have been widely studied in recent decades, but there is limited data on the effects of these elements on cancer survival. In this research, we examined whether blood concentrations of the heavy metals arsenic, cadmium, mercury and lead were associated with the overall survival of lung cancer patients. The study group consisted of 336 patients with lung cancer who were prospectively observed. Blood concentrations of heavy metals were measured to study the relationship between their levels and overall survival using Cox proportional hazards analysis. The hazard ratio of death from all causes was 0.99 (p = 0.94) for arsenic, 1.37 (p = 0.15) for cadmium, 1.55 (p = 0.04) for mercury, and 1.18 (p = 0.47) for lead in patients from the lowest concentration quartile, compared with those in the highest quartile. Among the patients with stage IA disease, this relationship was statistically significant (HR = 7.36 p 0.01) for cadmium levels in the highest quartile ( .97–7.77 µg/L) compared to quartile I (0.23–0.57 µg/L, reference). This study revealed that low blood cadmium levels .47 µg/L are probably associated with improved overall survival in treated patients with stage IA disease.
Publisher: International Society for Horticultural Science (ISHS)
Date: 11-2001
Publisher: Springer Science and Business Media LLC
Date: 23-09-2022
DOI: 10.1186/S42408-022-00145-4
Abstract: Climate change is eroding forest resilience to disturbance directly through warming climate and indirectly through increasing disturbance activity. Forests characterized by stand-replacing fire regimes and dominated by serotinous species are at risk when the inter-fire period is insufficient for canopy seed bank development and climate conditions for recruitment in the post-fire growing season are unsuitable. Although both factors are critical to serotinous forest persistence, their relative importance for post-fire regeneration in serotinous forests remains poorly understood. To assess the relative effects of each factor, we established plots in severely burned knobcone pine ( Pinus attenuata Lemmon) forests in Oregon and California, USA, representing a range of past fire intervals (6 to 31+ years). Specifically, we evaluated effects of fire interval and pre-fire canopy seed bank (proxies for seed supply) and post-fire climate on three metrics of post-fire tree regeneration (seedling density, probability of self-replacement, percent population recovery). Seed supply consistently had the strongest effect on post-fire regeneration. Between 6- and 31-year fire intervals, post-fire seedling density increased from 1000 to 100,000 seedlings ha −1 , while probability of self-replacement increased from ~ 0 to ~ 100% and percent population recovery increased from 20 to 2000% of the pre-fire population, respectively. Similarly, increasing the canopy seed bank by two orders of magnitude increased seedling density and percent population recovery by two orders and one order of magnitude, respectively, and increased the probability of self-replacement by 50%. Greater post-fire climatic moisture deficit exacerbated the effect of seed supply an additional 4–6 years between fires was required under high moisture stress conditions to reach similar regeneration levels as under low moisture stress conditions. The overriding effect of seed supply—strongly driven by pre-fire stand age—on post-fire regeneration suggests that altered fire frequency (an indirect effect of climate change) will have a profound impact on serotinous forests. Although direct effects of hot and dry climate are lower in magnitude, they can alter forest recovery where seed supply nears a threshold. These findings reveal how fire interval and climate combine to determine changes in forest cover in the future, informing management and vulnerability mapping.
Start Date: 2011
End Date: 2013
Funder: Australian Research Council
View Funded ActivityStart Date: 2002
End Date: 2004
Funder: Australian Research Council
View Funded ActivityStart Date: 2014
End Date: 2013
Funder: German Research Foundation
View Funded ActivityStart Date: 2013
End Date: 2015
Funder: Australian Research Council
View Funded ActivityStart Date: 2005
End Date: 2009
Funder: Australian Research Council
View Funded ActivityStart Date: 2007
End Date: 2009
Funder: Australian Research Council
View Funded ActivityStart Date: 2005
End Date: 2007
Funder: Australian Research Council
View Funded ActivityStart Date: 2004
End Date: 2006
Funder: Australian Research Council
View Funded ActivityStart Date: 2016
End Date: 2020
Funder: Australian Research Council
View Funded ActivityStart Date: 2003
End Date: 2007
Funder: Australian Research Council
View Funded ActivityStart Date: 2017
End Date: 2019
Funder: Australian Research Council
View Funded ActivityStart Date: 03-2013
End Date: 06-2017
Amount: $709,778.00
Funder: Australian Research Council
View Funded Activity