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Perry G.L.W.,University of Auckland | Enright N.J.,Murdoch University | Miller B.P.,Botanic Gardens and Parks Authority | Miller B.P.,University of Western Australia | Lamont B.B.,Curtin University Australia
Journal of Vegetation Science | Year: 2013

Questions: A species' spatial pattern is the outcome of a series of filters: demographic, disturbance, environmental and functional, all varying over space and time. To evaluate the importance of function as a filter we ask: (1) do a species' functional traits allow prediction of its fine-scale spatial patterning, and (2) how consistent is the fine-scale spatial pattern shown by the same species across multiple sites where the properties of the other filters may vary? Location: Species-rich Mediterranean climate shrublands of southwestern Australia's northern sandplains. Methods: Using fully mapped plots at four sites (each >10 000 individuals, 74-112 species), we characterized individual species spatial patterning using point pattern analyses. We classified species spatial patterns in three ways: (1) whether they departed from a null model controlling for first-order effects (i.e. are they aggregated?), (2) parameterization of Thomas cluster processes (what form does any clustering take?), and (3) their position in a multivariate 'pattern space' (do species show different types of pattern?). We then explored the extent to which a species' functional traits, abundance and/or the site at which it occurred predicted these three facets of its spatial pattern. Results: Although at all sites most species were aggregated, site was consistently important in predicting a species' spatial pattern. Regenerative response to fire - whether a species is killed by fire and recruits solely via seeds, or survives and resprouts vegetatively after fire - was the functional trait most consistently useful in predicting a species' spatial pattern. Fire-killed species tended to show more aggregated distributions than resprouters. Species present at multiple sites did not show consistency in their spatial patterns across those sites more than expected by chance alone. Conclusions: Although functional traits relating to fire responses and water use predict species spatial distributions at the landscape level, at the fine scales we considered site effects were as important as functional traits in explaining spatial pattern. Within and between site heterogeneity, some of which can be generated by the stochastic properties of fire, may mask the deterministic effects of species functional traits. © 2012 International Association for Vegetation Science. Source

Barrett R.L.,Botanic Gardens and Parks Authority | Barrett R.L.,University of Western Australia | Barrett R.L.,Bentley Delivery Center
Annals of Botany | Year: 2013

BackgroundSedges (Cyperaceae) form an important ecological component of many ecosystems around the world. Sword and rapier sedges (genus Lepidosperma) are common and widespread components of the southern Australian and New Zealand floras, also occurring in New Caledonia, West Papua, Borneo, Malaysia and southern China. Sedge ecology is seldom studied and no comprehensive review of sedge ecology exists. Lepidosperma is unusual in the Cyperaceae with the majority of species occurring in dryland habitats.ScopeExtensive review of ecological literature and field observations shows Lepidosperma species to be important components of many ecosystems, often dominating understorey and sedge-rich communities. For the first time, a detailed ecological review of a Cyperaceae genus is presented.Conclusions Lepidospermaspecies are long-lived perennials with significant abundance and persistence in the landscape. Speciation patterns in the genus are of considerable interest due to complex biogeographical patterns and a high degree of habitat specificity. Potential benefits exist for medicinal products identified from several Lepidosperma species. Over 178 organisms, including 26 mammals, 42 birds, six reptiles, five amphibians, eight arachnids, 75 insects, three crustaceans and 13 fungi, are found to be dependent on, or making use of, Lepidosperma species. A significant relationship exists between Lepidosperma species and the moth genus Elachista. Implications for the conservation and ecology of both sedges and associated species are discussed. © 2013 The Author. Source

Barrett R.L.,Botanic Gardens and Parks Authority | Barrett R.L.,University of Western Australia | Barrett R.L.,Bentley Delivery Center
Nuytsia | Year: 2013

Recent surveys in the North Kimberley have brought numerous new species to light. Studies have revealed considerable taxonomic complexity in the genus Solanum L. in the Kimberley region that requires the recognition of a number of new taxa. Solanum zoeae R.L. Barrett is described here following collection of the first fertile material on a remote sandstone outcrop on Doongan Station. Notes are provided on all phrase-named Solanum taxa currently recognised in the Kimberley region and a revised key to Solanum species in the Kimberley region is provided. © Department of Environment and Conservation 2013. Source

Barrett R.L.,Botanic Gardens and Parks Authority | Barrett R.L.,University of Western Australia | Wilson K.L.,Bentley Delivery Center
Australian Systematic Botany | Year: 2012

Species diversity in the genus Lepidosperma Labill. is much greater than previously thought. On the basis of morphological and molecular data, we currently recognise 73 named species (mainly in Australia), with many more species yet to be described. As a precursor to a complete revision, we review the names published in Lepidosperma. All published names at infrageneric, specific and infraspecific rank are typified and their current taxonomic status is indicated. Brief distribution notes are given for the 73 named species recognised. We also give a list of names referrable to other genera. A summary of the taxonomic history of the genus is provided, as well as notes on the specimens collected by early collectors in Australia. Three new combinations are made in Lepidosperma: L. asperatum (Kk.) R.L.Barrett, L. neozelandicum (Kk.) R.L.Barrett K.L.Wilson and L. rigidulum (Kk.) K.L.Wilson. L. sanguinolentum K.L.Wilson is a nomen novum based on L. drummondii var. floribundum Kk. Lectotypes are designated for eight infrageneric names and for 39 specific and infraspecific names, including the following: L. angustifolium Hook.f., L. angustatum R.Br., L. angustatum var. curvispiculum Benth., L. australe (A.Rich.) Hook.f., L. benthamianum C.B.Clarke, L. brunonianum Nees, L. brunonianum var. binuciferum Kk., L. canescens Boeckeler, L. carphoides Benth., L. concavum var. pyramidatum Benth., L. confine Nees, L. costale Nees, L. costale var. densispicatum Kk., L. drummondii Benth., L. effusum Benth., L. forsythii A.A.Ham., L. gladiatum Labill., L. globosum Labill., L. inops F.Muell. ex Rodway, L. laterale var. angustum Benth., L. laterale var. majus Benth., L. leptophyllum Benth., L. leptostachyum Benth., L. leptostachyum var. asperatum Kk., L. muelleri Boeckeler, L. neesii Kunth, L. perplanum Guillaumin, L. perteres C.B.Clarke, L. pruinosum Kk., L. pruinosum var. rigidulum Kk., L. quadrangulatum A.A.Ham., L. resinosum var. pleianthemum Kük., L. scabrum Nees, L. scabrum var. effusum Benth., L. sieberi Kunth, L. squamatum Labill., L. tenue Benth., L. viscidum R.Br. and L. viscidum var. subpyramidale Kk. Twenty-two excluded names are listed and new combinations are provided in Tricostularia for L. aphyllum R.Br. and L. exsul C.B.Clarke. A lectotype is selected for L. pauciflorum F.Muell. (=Tricostularia pauciflora (F.Muell.) Benth.). © CSIRO 2012. Source

Fontaine J.B.,Murdoch University | Westcott V.C.,University of Melbourne | Enright N.J.,Murdoch University | Lade J.C.,University of Melbourne | Miller B.P.,Botanic Gardens and Parks Authority
International Journal of Wildland Fire | Year: 2012

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. © IAWF 2012. Source

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