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Background: Tea tree (Melaleuca alternifolia) oil is an essential oil that is steam distilled from the leaves of the tea tree, native to Australia. The oil has fresh and pleasant odour and some medicinal properties of odour eliminating as well as antibacterial and antiseptic action. Tea tree oil has found increasing use in certain consumer products including cosmetics. Tea tree oil components will vary depending on the growing environment including air and sunlight conditions. Methods: The present study on estimation and seasonal variation on essential oils from different plant parts of tea tree was carried by hydro distillation method. Result: The study reveals that, the needle leaves and flowers have the higher oil content of 2.30% and 2.25% respectively. The effect of months on different plant parts showed that the oil recovery from needle leaves and flowers were higher during the month of July and August. [ABSTRACT FROM AUTHOR]

Premise: Within closed‐canopy forests, vertical gradients of light and atmospheric CO2 drive variations in leaf carbon isotope ratios, leaf mass per area (LMA), and the micromorphology of leaf epidermal cells. Variations in traits observed in preserved or fossilized leaves could enable inferences of past forest canopy closure and leaf function and thereby habitat of individual taxa. However, as yet no calibration study has examined how isotopic, micro‐ and macromorphological traits, in combination, reflect position within a modern closed‐canopy forest or how these could be applied to the fossil record. Methods: Leaves were sampled from throughout the vertical profile of the tropical forest canopy using the 48.5 m crane at the Daintree Rainforest Observatory, Queensland, Australia. Carbon isotope ratios, LMA, petiole metric (i.e., petiole‐width2/leaf area, a proposed proxy for LMA that can be measured from fossil leaves), and leaf micromorphology (i.e., undulation index and cell area) were compared within species across a range of canopy positions, as quantified by leaf area index (LAI). Results: Individually, cell area, δ13C, and petiole metric all correlated with both LAI and LMA, but the use of a combined model provided significantly greater predictive power. Conclusions: Using the observed relationships with leaf carbon isotope ratio and morphology to estimate the range of LAI in fossil floras can provide a measure of canopy closure in ancient forests. Similarly, estimates of LAI and LMA for individual taxa can provide comparative measures of light environment and growth strategy of fossil taxa from within a flora. [ABSTRACT FROM AUTHOR]

Forty-seven lucerne varieties/lines were examined to quantify their morphological, production characteristics, and nutritive values in southeastern Australia. The experiment was established in 2015 with a randomized complete block design and four replications. The morphological and production characteristics were measured from January to October 2017, and nutritive values were measured in February 2017. The results showed that the cultivars differed significantly (P < 0.01) in morphological, production characteristics, and nutritive values. Total herbage yield was highest for Haymaster 7 (14,186 kg/ha) and lowest for Qingshui (5927 kg/ha). Plant height was highest for Cropper 9.5 (31.4 cm) and lowest for Qingshui (14.5 cm). SF 714QL had the greatest branch number (44.7 branches/15 cm row segment). AV1001 had longest leaf (2.3 cm) and greatest leaf area (16.68 cm2/10 leaves) whereas Force 10 and SARDI 10 SERIES 2 had widest leaves (1.3 cm). AV1005 had the highest leaf-to-stem ratio (5.64). Crude protein (CP) content was highest for SARDI 10 SERIES 2 (15.1%) and lowest for SF 714QL (8.0%). AV12 was highest in crude fat (4.5%). Neutral detergent fiber (NDF) content was lowest in Stamina 5 (33.5%). Acid detergent fiber (ADF) content was lowest in Gannong 4 (29.3%). Relative feed value (RFV) was highest in Force 11 (193.0%). Calcium (Ca) content was highest for Titan 5 (1.8%). Phosphorous content was highest for AV1 and Gannong 6 (0.1%). Overall, Cropper 9.5, SARDI 10 SERIES 2, Haymaster 9, Titan 9, SF 714QL, Kaituna, Haymaster 7, AV1001, AV1002, and WL925HQ performed well based on their comprehensive scores. Abbreviations: CP - crude protein; CF - crude fat; NDF - neutral detergent fiber; ADF - acid detergent fiber; Ca - calcium; P - phosphorus; RFV - relative feed value. [ABSTRACT FROM AUTHOR]

Phylogenetic analyses imply that monocots were a key group in the early radiation of angiosperms, yet they are much rarer than other major clades in the Early Cretaceous macrofossil record. Here we describe a well-preserved leaf and several inflorescences related to the near-basal monocot family Araceae and abundant monocot leaves of uncertain affinities from two latest Albian localities in north-eastern Spain. Orontiophyllum ferreri sp. nov. has a multistranded midrib, several orders of parallel-pinnate veins, two orders of transverse veins, and paracytic-oblique stomata. This suite of characters (but with both anomocytic and paracytic-oblique stomata) is characteristic today of Orontium in the near-basal araceous subfamily Orontioideae, and later Cretaceous and early Cenozoic leaves assigned to Orontiophyllum have similar architecture. Sedimentology and anatomy suggest a (semi)aquatic ecology. Other monocot leaves at the same locality are linear and parallel-veined but have similar stomata. Although anomocytic stomata have been proposed as ancestral in monocots, O. ferreri, the associated linear leaves, Albian–Cenomanian cuticles from Australia and Portugal, and extant data are consistent with the hypothesis that variable paracytic-oblique stomata are ancestral. Turolospadix bogneri gen. et sp. nov., from the other locality, includes spadices of ebracteate flowers with four tepals, a central gynoecium, and a long stipe (vs a spathe attached just below the fertile zone as in most Araceae). Phylogenetic analyses indicate that the character combinations seen in O. ferreri and T. bogneri are ancestral for Araceae, and they could be either sister to Araceae or nested within a basal grade of the family. Together with fossils from the Aptian–Albian of Brazil and Portugal, the Spanish fossils indicate that Araceae are among the oldest extant monocot families, but they were associated with diverse linear-leaved monocots of uncertain affinities. [ABSTRACT FROM AUTHOR]

Introduction: Xanthophyllum fragrans C.T. White is a rainforest tree that is native to north-eastern regions of Australia. X. fragrans leaf extracts were examined for the ability to inhibit the growth of Pseudomonas aeruginosa. Methods: The antimicrobial activity of a methanolic X. fragrans leaf extracts were investigated by disc diffusion and growth time course assays against P. aeruginosa. The growth inhibitory activity was further quantified by MIC determination. Toxicity was determined using the Artemia franciscana nauplii bioassay. Results: The methanolic X. fragrans leaf extract was a potent inhibitor of P. aeruginosa growth (MICs of 430 and 1687µg/mL against the reference and clinical strains respectively). The aqueous X. fragrans leaf extract was also a moderate inhibitor of P. aeruginosa growth (MICs approximately 1000 and 2500µg/mL against the reference and clinical bacterial strains respectively). The antibacterial activities of the methanolic X. fragrans leaf extracts were further investigated using growth time course assays that showed significant growth inhibition in cultures of P. aeruginosa within 1 h of exposure. All extracts were determined to be non-toxic in the Artemia franciscana nauplii bioassay, indicating their safety for use in preventing diseases caused by these pathogens. Conclusion: The lack of toxicity of the X. fragrans leaf extracts and their growth inhibitory bioactivity against P. aeruginosa indicates their potential in the development of new therapies targeting this bacterium. [ABSTRACT FROM AUTHOR]

• Teratosphaeria leaf blight (TLB), caused by six related species, is the most serious leaf disease of plantation Eucalyptus. • Recently, T. destructans has spread from south-east Asia to South Africa and T. pseudoeucalypti from Australia to South America. • Management of TLB will involve breeding and selection of tolerant/resistant clones, matching species to site and conditionsoptimal growth in order to reduce stress related disease impacts. • Of paramount concern is the need for more sophisticated and stringent biosecurity measures to reduce the introduction of new pathogens and pathotypes. In Australia, during the course of the last two decades, plantation area of Eucalyptus has expanded dramatically. One of the most important threats to these trees, and to the forest industries they sustain, is a complex of fungal diseases broadly treated as Teratosphaeria Leaf Blight. The aim of this review is to summarise some of the most important findings relating to Teratosphaeria spp. (previously Kirramyces) associated with leaf and shoot blight of Eucalyptus. The review spans a period of 23 years since the description of the aptly named Teratosphaeria destructans. Six species of Teratosphaeria are associated with leaf and shoot blights of Eucalyptus and these are T. destructans , T. eucalypti , T. novaehollandiae , T. pseudoeucalypti , T. viscida and T. tiwiana. With the exception of T. destructans, all of these species have been found in Australia. Based on the damage they cause, the most significant of these fungi are T. destructans , T. pseudoeucalypti and T. viscida. Teratosphaeria viscida has been found only in the tropics of eastern Australia, while T. destructans and T. pseudoeucalypti have spread globally; T. destructans throughout Asia and South Africa and T. pseudoeucalypti into South America. Factors driving the development of these diseases have included the establishment of plantations adjacent to native eucalypt forests in Australia and planting on sites not favourable to the growth of the host trees. These factors, in conjunction with a lack of selection for resistance to emerging pathogens, lack of resilience to disease in monocultures, and the movement of pathogens with planting stock and seeds around the globe have led to substantial losses. Based on the Teratosphaeria leaf blight example, it is clear that more effective forest management and more stringent biosecurity measurements will be a required to sustain eucalypt plantations globally. [ABSTRACT FROM AUTHOR]

Arboreal folivores are particularly vulnerable to the impacts of extreme climate change-driven heatwaves and droughts as they rely on leaf moisture to maintain hydration. During these increasingly frequent and intense weather events, leaf water content may not be enough to meet their moisture requirements, potentially leading to large-scale mortality due to dehydration. Water supplementation could be critical for the conservation of these animals. We tested artificial water stations for a threatened arboreal folivore, the koala (Phascolarctos cinereus), as a potential mitigation measure during hot and dry weather in New South Wales, Australia. We provided ground and tree drinkers to koalas and investigated changes in use with season, environmental conditions and foliar moisture. Our study provides first evidence of the regular use of free water by koalas. Koalas used supplemented water extensively throughout the year, even during cooler months. Time spent drinking varied with season and depended on days since last rain and temperature. The more days without rain, the more time koalas spent drinking. When temperature was high, visits to water stations were more frequent, indicating that in hot weather koalas need regular access to free water. Our results suggest that future changes in rainfall regimes and temperature in Australia have the potential to critically affect koala populations. Our conclusions can be applied to many other arboreal folivorous mammals worldwide which rely on leaves for their nutritional and water requirements. Artificial water stations may facilitate the resilience of vulnerable arboreal folivores during heat and drought events and may help mitigate the effects of climate change. [ABSTRACT FROM AUTHOR]

Abstract Callitris Vent., is the most speciose of the Southern Hemisphere Cupressaceae (conifer) genera, with species indigenous to Australia and New Caledonia. While most other Southern Hemisphere conifers are restricted to wet climates, Callitri s species occupy a broad range of habitats, from the margins of rainforests to arid Australia. This study examines fossilized Callitri s foliage collected from three south-eastern Australian sites ranging in age from middle Miocene to the Last Interglacial. The oldest, middle Miocene, fossils are from Yallourn, southern Victoria and represent a new (extinct) species, Callitris blackburnii. Much younger, early Pleistocene (~ 1.59 Ma), fossils are from four slightly different aged horizons within the Stony Creek Basin, western Victorian uplands. One of these specimens is consistent with extant C. rhomboidea R.Br. ex Rich. & A. Rich. in both morphology and size. Specimens from other depths in the Stony Creek sediments are assigned to another extant species, C. columellaris F. Muell., but are smaller in size than the extant species. The youngest fossil specimens (Last Interglacial (~ 110 ka) Yarra Creek, King Island) are assigned to extant C. rhomboidea. The findings of this study enhance the previously sparse fossil record of Callitris and further indicate that two widespread extant Callitris species have been present in south-eastern Australia for at least ~ 1.5 million years. Highlights • Callitris fossil foliage record enhanced by discoveries from three South Eastern Australian sites. • Middle Miocene Callitris assigned to new species, Callitris blackburnii. • Early Pleistocene Callitris consistent with extant species, C. rhomboidea and C. columellaris. • Last interglacial Callitris assigned to extant C. rhomboidea. [ABSTRACT FROM AUTHOR]

Abstract The bioassay-guided isolation of new anti-inflammatory metabolites from the Australian Indigenous plant Angophora costata led to the discovery of three new 4-phenylcoumarins, costatamins A – C (1–3). The structures were determined by detailed spectroscopic analysis. Costatamins A – C were evaluated for their inhibitory effects on (a) NO production and (b) TNF-α release in RAW 264.7 macrophages, displaying an IC(50) value of 20–30 μg/mL for both the inflammatory markers. Graphical abstract Unlabelled Image [ABSTRACT FROM AUTHOR]

Graphical abstract Ginkgo biloba Quality Control Decision Tree. Unlabelled Image [ABSTRACT FROM AUTHOR]

Recent reports of Eremophila glabra (R.Br.) Ostenf. (Scrophulariaceae) displaying antibacterial activity has led us to investigate the bioactive secondary metabolites responsible for this activity. Bioassay-directed fractionation of solvent extracts prepared from the leaves of E. glabra led to the isolation of seven serrulatane diterpenes, three flavonoids and the caffeoyl ester disaccharide verbascoside. Among these, four serrulatanes, namely 18-acetoxy-8, 20-dihydroxyserrulat-14-en-19-oic acid ( 14 ), 18,20-diacetoxy-8-hydroxyserrulat-14-en-19-oic acid ( 16 ), 8,18,20-triacetoxyserrulat-14-en-19-oic acid ( 17 ) and 18-acetoxy-8-hydroxyserrulat-14-en-19-oic acid ( 18 ) are described for the first time, while 8,20-diacetoxyserrulat-14-en-19-oic acid ( 3 ), 8,18,20-trihydroxyserrulat-14-en-19-oic acid ( 5 ) and 20-acetoxy-8-hydroxyserrulat-14-en-19-oic acid ( 19 ) were previously reported. All three flavonoids hispidulin ( 12 ), jaceosidin ( 13 ) and cirsimaritin ( 15 ) are known but reported for the first time in E. glabra. All compounds were tested in an agar diffusion antimicrobial assay against Staphylococcus aureus (NCTC 10442) and Staphylococcus epidermidis (ATCC 14990). Compounds 12 , 13 , 17 , 18 and 19 exhibited moderate activity, with minimum inhibitory concentrations (MICs) ranging from 32 to 512 μg/mL. Compound 19 demonstrated the highest activity against S. epidermidis ATCC 14990 with MIC of 32 μg/mL, while 13 demonstrated the highest activity against S. aureus NCTC 10442 with MIC of 128 μg/mL. [ABSTRACT FROM AUTHOR]

Tomato spotted wilt virus (TSWV) causes sporadic but serious disease in Australian potato crops. TSWV is naturally spread to potato by thrips of which Thrips tabaci is the most important. Prior studies indicated possible non-preference of potato cultivars to T. tabaci. Select potato cultivars were assessed for non-preference to T. tabaci in paired and group choice trials. Cultivars ‘Bismark’, ‘Tasman’ and ‘King Edward’ were less preferred than ‘Atlantic’, ‘Russet Burbank’ and ‘Shepody’. Green leaf volatiles were sampled using solid-phase microextraction from the headspace of potato cultivars of two ages that differed in T. tabaci preference. Analysis of headspace volatile data using Receiver Operating Characteristic curves identified individual volatiles associated with T. tabaci preference and non-preference, young and old plants and individual cultivars. These data could be used to inform breeding programs for selection of T. tabaci resistance to assist with TSWV management, and biological testing of novel thrips management compounds. [ABSTRACT FROM AUTHOR]

Plant functional traits are increasingly used to generalize across species, however few examples exist of predictions from trait-based models being evaluated in new species or new places. Can we use functional traits to predict growth of unknown species in different areas? We used three independently collected datasets, each containing data on heights of individuals from non-resprouting species over a chronosquence of time-since-fire sites from three ecosystems in south-eastern Australia. We examined the influence of specific leaf area, woody density, seed size and leaf nitrogen content on three aspects of plant growth; maximum relative growth rate, age at maximum growth and asymptotic height. We tested our capacity to perform out-of-sample prediction of growth trajectories between ecosystems using species functional traits. We found strong trait-growth relationships in one of the datasets; whereby species with low SLA achieved the greatest asymptotic heights, species with high leaf-nitrogen content achieved relatively fast growth rates, and species with low seed mass reached their time of maximum growth early. However these same growth-trait relationships did not hold across the two other datasets, making accurate prediction from one dataset to another unachievable. We believe there is evidence to suggest that growth trajectories themselves may be fundamentally different between ecosystems and that trait-height-growth relationships may change over environmental gradients. [ABSTRACT FROM AUTHOR]

Willows ( Salix spp.) are listed as a weed of national significance in Australia. Despite this recognition, functional effects of willows on streams compared to native species are largely unknown. Leaves supply carbon to instream food webs, but may also act as surfaces for biofilm, and thus can contribute in different ways to stream metabolism. Salix fragilis L. and Eucalyptus camaldulensis Dehnh. leaves that had been colonised by biofilms were placed into chambers in laboratory conditions, and metabolic rates were measured. Gross Primary Production (GPP) of biofilms on E. camaldulensis leaves after 10 days of incubation were significantly greater than biofilms on S. fragilis leaves. S. fragilis leaves displayed greater rates of microbial decomposition per leaf mass. Autotrophic biomass was one hundred fold greater on E. camaldulensis leaves. The biofilm on E. camaldulensis leaves is likely to support a greater population of grazers, compared to S. fragilis. The alien S. fragilis leaves, therefore, are fuelling a different component of the food web to endemic E. camaldulensis leaves. Endemic Eucalyptus spp. leaves play an important role in temperate Australian streams as a substrate for autotrophic growth and provide a year round pathway for carbon to reach secondary invertebrate consumers. [ABSTRACT FROM AUTHOR]

Phytochemical investigation of the leaves of the Australian rainforest tree Cryptocarya mackinnoniana led to the discovery of three new oxygenated phenyl alkyl acids, cryptocaryoic acids A – C and two known compounds, cryptocaryone and 2′,6′-dihydroxy-4′-methoxychalcone. The structures of all the compounds were determined by detailed spectroscopic analysis. Mosher's analysis was used for absolute stereochemistry determination at C-11, while the remaining stereochemistry determination of the one remaining stereocenter C-13 was based on NOESY correlations. All compounds isolated were also evaluated for their anti-inflammatory properties by assessing their inhibitory effects on LPS and interferon-γ induced nitric oxide (NO) production and TNF- α release in RAW 264.7 macrophages. The new cryptocaryoic acids exhibited weak to moderate anti-inflammatory activity (NO inhibition) ranging from (18.4–56 μM). [Display omitted] • Three new phenyl alkyl acids, cryptocaryoic acids A – C, were isolated from the leaves of Cryptocarya mackinnoniana • Cryptocaryoic acids exhibited weak to moderate anti-inflammatory activity • Cryptocaryoic acids are the first in the series of molecules bearing the phenyl oxy-alkyl acid from C.mackinnoniana [ABSTRACT FROM AUTHOR]

Background The foraging choices of honey bees are influenced by many factors, such as floral aroma. The composition of volatile compounds influences the bioactivity of the aromatic plants and honey produced from them. In this study, Agastache rugosa was evaluated as part of a project to select the most promising medicinal plant species for production of bioactive honey. Methods Headspace solid-phase microextraction HS-SPME /GC-MS was optimized to identify the volatile bioactive compounds in the leaves, flower spikes, and for the first time, the flower nectar of Australian grown A. rugosa. Results Methyl chavicol (= estragole) was the predominant headspace volatile compound in the flowers with nectar, flower spikes, and leaves, with a total of 97.16%, 96.74% and 94.35%, respectively. Current results indicate that HS-SPME/GC-MS could be a useful tool for screening estragole concentration in herbal products. Conclusion Recently, estragole was suspected to be carcinogenic and genotoxic, according to the European Union Committee on Herbal Medicinal Products. Further studies are needed on safe daily intake of Agastache as herbal tea or honey, as well as for topical uses. [ABSTRACT FROM AUTHOR]

The percentage of woody dicots with entire-margined leaves in a flora is known to be positively correlated with mean annual temperature (Leaf Margin Analysis — LMA) but this relationship is not globally uniform. In particular the floras of Australia and New Zealand have been regarded as displaying a different physiognomic relationship to climate than floras seen in the Northern Hemisphere. This difference is more marked in New Zealand where the LMA relationship appears entirely absent. Here we amass data for both Northern and Southern hemispheres using standard protocols and show that regional variations in the leaf margin–mean annual temperature relationship are real but become less significant when other characters are included. Even New Zealand falls into line and most of the mean annual temperature signal in New Zealand floras is encoded in non-margin features. We introduce a new CLAMP (Climate Leaf Analysis Multivariate Program) calibration dataset for the Southern Hemisphere, comprising leaf physiognomic data from Argentina, Bolivia, South Africa, Australia, New Zealand and other Pacific Islands that offers comparable precision for climate prediction to similar datasets derived from the Northern Hemisphere. [ABSTRACT FROM AUTHOR]

Abstract: Leaf floras in fluvial–lacustrine sediments of the Upper Cretaceous (Cenomanian–Turonian) portion of the Winton Formation suggest a community with co-dominance of angiosperms, conifers, ginkgo and other seed plants. To date wood floras associated with the Winton Formation have not been examined in detail. Winton Formation wood has been presumed to comprise araucarian, podocarp and taxodiaceous components, but this has been based largely on the identification of other plant macro and microfossils. Here we describe a new species of podocarp fossil wood from the genus Protophyllocladoxylon based on eleven specimens of silicified wood found as surface material at two broadly coeval sites in the Cenomanian–Turonian portion of the Winton Formation: QM L311 and Bladensburg National Park. The new species is characterised by the presence of araucaroid tracheid pitting and phyllocladoid oopores, the absence of oculipores, and the paired arrangement of the oopores within the crossfields. The recognition of Protophyllocladoxylon in the Winton Formation supports previous palynological frequency counts that suggest a dominance of podocarp conifers. [Copyright &y& Elsevier]

Mangrove forests act as a natural filter of land-derived wastewaters along industrialized tropical and sub-tropical coastlines and assist in maintaining a healthy living condition for marine ecosystems. Currently, these intertidal communities are under serious threat from heavy metal contamination induced by human activity associated with rapid urbanization and industrialization. Studies on the biotic responses of these plants to heavy metal contamination are of great significance in estuary management and maintaining coastal ecosystem health. The main objective of the present investigation was to assess the biotic response in Avicennia marina ecosystems to heavy metal contamination through the determination of metal concentrations in leaves, fine nutritive roots and underlying sediments collected in fifteen locations across Sydney Estuary (Australia). Metal concentrations (especially Cu, Pb and Zn) in the underlying sediments of A. marina were enriched to a level (based on Interim Sediment Quality Guidelines) at which adverse biological effects to flora could occasionally occur. Metals accumulated in fine nutritive roots greater than underlying sediments, however, only minor translocation of these metals to A. marina leaves was observed (mean translocation factors, TFs, for all elements <0.13, except for Mn). Translocation factors of essential elements (i.e., common plant micro-nutrients, Cu, Ni, Mn and Zn) were greater than non-essential elements (As, Cd, Co, Cr and Pb), suggesting that A. marina mangroves of this estuary selectively excluded non-essential elements, while regulating essential elements and limiting toxicity to plants. This study supports the notion that A. marina mangroves act as a phytostabilizer in this highly modified estuary thereby protecting the aquatic ecosystem from point or non-point sources of heavy metal contamination. [ABSTRACT FROM AUTHOR]

Abstract: Ethnopharmacological significance: Eremophila longifolia is one of the most respected of the traditional medicines used by Australian Aboriginal people. Customary use involves smoldering the leaves over hot embers of a fire to produce an acrid smoke, believed to have therapeutic effects broadly consistent with antimicrobial, antifungal and anti-inflammatory capacity. Aim of the study: The current study aims to examine the contribution of partially pyrolysed and non-pyrolysed essential oils in traditional usage of Eremophila longifolia. Materials and methods: Non-pyrolysed and partially pyrolysed essential oils were produced by hydrodistillation and part-wet/part-dry distillation, respectively. All samples were tested for antimicrobial activity by broth dilution. Some of these samples were further treated to an incrementally stepped temperature profile in a novel procedure employing a commercial thermocycler in an attempt to mimic the effect of temperature gradients produced during smoking ceremonies. Components from the pyrodistilled oils were compared with the non-pyrodistilled oils, using GC–MS, GC-FID and HPLC-PAD. The 2,2-diphenyl-1-picrylhydrazyl method, was used to compare free radical scavenging ability. Results: Partially pyrolysed oils had approximately three or more times greater antimicrobial activity, enhanced in cultures warmed incrementally to 60°C and held for 30s and further enhanced if held for 2min. Partially pyrolysed oils showed a radical scavenging capacity 30–700 times greater than the corresponding non-pyrolysed oils. HPLC-PAD revealed the presence of additional constituents not present in the fresh essential oil. Conclusion: These results, by showing enhanced antimicrobial and antioxidant activities, provide the first known Western scientific justification for the smoking ceremonies involving leaves of Eremophila longifolia. During customary use, both partially pyrolysed as well as non-pyrolysed essential oils may contribute significantly to the overall intended medicinal effect. [Copyright &y& Elsevier]

The article discusses the taxonomic status of Grimmia procumbens. This species was described in 1882 by W. Mitten from material collected by Ferdinand von Muller in Australia. The plant is small and slender and grow in loose tufts. It is identical to Bucklandiella sudetica, based on the undifferentiated perichaetial leaves, the structure of the costa, leaf margins, and basal marginal cells.

Abstract: Ethnopharmacological significance: Although no known medicinal use for Pittosporum undulatum Vent. (Pittosporaceae) has been recorded, anecdotal evidence suggests that Australian Aboriginal people used Pittosporum angustifolium Lodd., G. Lodd. & W. Lodd. topically for eczema, pruritis or to induce lactation in mothers following child-birth and internally for coughs, colds or cramps. Aims of the study: Essential oil composition and bioactivity as well as differential solvent extract antimicrobial activity from Pittosporum angustifolium are investigated here first, to partially describe the composition of volatiles released in traditional applications of Pittosporum angustifolium for colds or as a lactagogue, and second to investigate antibacterial activity related to topical applications. Essential oils were also investigated from Pittosporum undulatum Vent., first to enhance essential oil data produced in previous studies, and second as a comparison to Pittosporum angustifolium. Materials and methods: Essential oils were hydrodistilled from fruit and leaves of both species using a modified approach to lessen the negative (frothing) effect of saponins. This was achieved by floating pumice or pearlite obsidian over the mixture to crush the suds formed while boiling. Essential oil extracts were analysed using GC–MS, quantified using GC-FID then screened for antimicrobial activity using a micro-titre plate broth dilution assay (MIC). Using dichloromethane, methanol, hexane and H2O as solvents, extracts were produced from leaves and fruit of Pittosporum angustifolium and screened for antimicrobial activity and qualitative phytochemical character. Results: Although the essential oil from leaves and fruit of Pittosporum undulatum demonstrated some component variation, the essential oil from fruits of Pittosporum angustifolium had major constituents that strongly varied according to the geographical location of collection, suggesting the existence of at least two chemotypes; one with high abundance of acetic acid decyl ester. This chemotype had high antimicrobial activity whilst the other chemotype had only moderate antimicrobial activity against the three microbial species investigated here. This result may support the occurrence of geographical specificity with regard to ethnopharmacological use. Antimicrobial activity screening of the solvent extracts from Pittosporum angustifolium revealed the leaves to be superior to fruit, with water being the most suitable extraction solvent. Conclusion: To the best of our knowledge, this study constitutes the first time essential oils, and solvent extracts from the fruits of Pittosporum angustifolium, have been examined employing comprehensive chemical and biological analysis. The essential oil composition presented in this paper, includes components with structural similarity as chemosemiotic compounds involved in mother–infant identification, which may have significance with regard to traditional applications as a lactagogue. [Copyright &y& Elsevier]

Cuticle thickness of leaves varies > 100 times across species, yet its dry mass cost and ecological benefits are poorly understood. It has been repeatedly demonstrated that thicker cuticle is not superior as a water barrier, implying that other functions must be important., Here, we measured the mechanical properties, dry mass and density of isolated cuticle from 13 evergreen woody species of Australian forests., Summed adaxial and abaxial cuticle membrane mass per unit leaf area ( CMA) varied from 2.95 to 27.4 g m−2 across species, and accounted for 6.7-24% of lamina dry mass. Density of cuticle varied only from 1.04 to 1.24 g cm−3; thus variation in CMA was mostly due to variation in cuticle thickness. Thicker cuticle was more resistant to tearing. Tensile strength and modulus of elasticity of cuticle were much higher than those of leaf laminas, with significant differences between adaxial and abaxial cuticles., While cuticle membranes were thin, they could account for a significant fraction of leaf dry mass due to their high density. The substantial cost of thicker cuticle is probably offset by increased mechanical resistance which might confer longer leaf lifespans among evergreen species. [ABSTRACT FROM AUTHOR]

Abstract: A study on the growth of Rhizophora stylosa Griff. was undertaken in three estuaries spanning the southernmost 265km of its range at its latitudinal limit in eastern Australia. A shoot tracking methodology was devised to follow vegetative phenological patterns and branching and to derive indices of relative growth between trees. Despite an apparent expansionary phase in distribution and a recent increased trend in mean temperature, comparisons of growth in the three estuaries do not suggest a latitudinal cline. The phenologies of leaf gain and leaf loss are generally comparable between R. stylosa in New South Wales and elsewhere, as is the rate of growth assessed by leaf initiation. However, leaf longevity and the number of leaves held on the shoot appears to be overall greater in NSW than in lower latitudes, perhaps as an adaptive response to lower levels of assimilation. This study suggests that R. stylosa is not close to physiological limits at the end of its range, supporting a contention that its current known southern limit is not at an absolute thermal boundary. [Copyright &y& Elsevier]

A new species of gall midge, Austroacacidiplosis botrycephalae Kolesik gen. et sp. n. induces conspicuous spherical, often red coloured, galls on leaves of Acacia deanei (R. T. Baker), Acacia decurrens Willd., Acacia baileyana F. Muell. and Acacia dealbata Link in south-eastern Australia. A new genus is erected to contain the new species. Austroacacidiplosis belongs to the tribe Cecidomyiini and its closest relative is Acacidiplosis Gagné, an African genus containing species that induce galls on leaves and flower buds of acacias in Kenya. [ABSTRACT FROM AUTHOR]

Abstract: Effective leaf area index (LAI) retrievals from a scanning, ground-based, near-infrared (1064nm) lidar that digitizes the full return waveform, the Echidna Validation Instrument (EVI), are in good agreement with those obtained from both hemispherical photography and the Li-Cor LAI-2000 Plant Canopy Analyzer. We conducted trials at 28 plots within six stands of hardwoods and conifers of varying height and stocking densities at Harvard Forest, Massachusetts, Bartlett Experimental Forest, New Hampshire, and Howland Experimental Forest, Maine, in July 2007. Effective LAI values retrieved by four methods, which ranged from 3.42 to 5.25 depending on the site and method, were not significantly different (β<0.1 among four methods). The LAI values also matched published values well. Foliage profiles (leaf area with height) retrieved from the lidar scans, although not independently validated, were consistent with stand structure as observed and as measured by conventional methods. Canopy mean top height, as determined from the foliage profiles, deviated from mean RH100 values obtained from the Lidar Vegetation Imaging Sensor (LVIS) airborne large-footprint lidar system at 27 plots by −0.91m with RMSE=2.04m, documenting the ability of the EVI to retrieve stand height. The Echidna Validation Instrument is the first realization of the Echidna® lidar concept, devised by Australia''s Commonwealth Scientific and Industrial Research Organization (CSIRO), for measuring forest structure using full-waveform, ground-based, scanning lidar. [Copyright &y& Elsevier]

Tropical rain forests have more species-rich tree assemblages than forests at higher latitudes, but is this because they comprise a wider array of niches or functional types? We address this by considering one tree functional type - light-demanding canopy trees with fast foliage turnover and growth - that is common in the tropics and subtropics, but virtually absent from mid-latitude rain forests. Although often referred to as 'tall pioneers' or 'large pioneers', they are by no means confined to early-successional stages, also recruiting directly to the canopy in old-growth stands by rapid growth beneath tree-fall gaps. We also explored the influence of latitude on tree-fall gap light environments as a possible constraint on the geographic distribution of this functional type, using the YPLANT program to simulate light interception and potential carbon gain by seedlings of the Australian rain forest pioneer Polyscias murrayi beneath idealized gaps at tropical, subtropical and cool temperate sites (latitudes 17, 29 and 42°S, respectively). P. murrayi grows quickly to heights of 20-25 m, has high photosynthetic capacity and respiration rates, and a leaf life span of 6-9 months. Simulated light interception and potential carbon gain were strongly influenced by latitude, and by the interaction of latitude with position within an idealized tree-fall gap of 100 m. Potential net daily carbon gain of P. murrayi was strongly positive beneath the gap centre at latitude 17, and beneath the poleward (i.e. southern) gap margin at latitude 29, but negative beneath both the gap centre and margin at latitude 42. Light interception and carbon gain were also influenced by geographic variation in sunshine hours, which were highest at latitude 29 and lowest at latitude 42. A larger gap of 300 m permitted positive net carbon gain at all latitudes, although rates were again predicted to be highest beneath the gap centre in the tropics. Synthesis. YPLANT simulations supported the hypothesis that sun angles could prevent trees with high metabolic rates from invading old-growth mid-latitude rain forests, where light environments suitable for their establishment will be scarce. Geographic variation in forest light environments is therefore likely to influence the range of viable functional types at different latitudes. [ABSTRACT FROM AUTHOR]

Quantification of landscape-based vegetation structural variation and pattern is a significant goal for a variety of ecological, monitoring and biodiversity studies. Vegetation structural metrics, derived from airborne laser scanning (ALS or aerial light detection and ranging-LiDAR) and QuickBird satellite imagery, were used to establish the degree of plot-based vegetation variation at a hillslope scale. Topographic position is an indicator of energy and water availability, and was quantified using DEM-based insolation and topographic wetness, respectively, stratifying areas into hot-warm-cold and wet-moist-dry topographic classes. A range of vegetation metrics-maximum and modal canopy height, crown cover, foliage cover, NDVI and semivariance-were compared among randomly selected plots from each topographic class. NDVI increases with increasing landscape wetness, whereas ALS-derived foliage cover decreases with increasing insolation. Foliage cover is well correlated with crown cover (R 2 =0.65), and since foliage cover is readily calculable for whole-of-landscape application, it will provide valuable and complementary information to NDVI. Between-plot heterogeneity increases with increasing wetness and decreasing insolation, indicating that more sampling is required in these locations to capture the full range of landscape-based variability. Pattern analysis in landscape ecology is one of the fundamental requirements of landscape ecology, and the methods described here offer statistically significant, quantifiable and repeatable means to realise that goal at a fine spatial grain. [ABSTRACT FROM AUTHOR]

Ethnopharmacological relevance: Extracts of the medicinal plant species Dodonaea polyandra were investigated as part of a collegial research partnership between Northern Kaanju traditional owners represented by Chuulangun Aboriginal Corporation (centred on the Wenlock and Pascoe Rivers, Cape York Peninsula, Queensland, Australia) and university-based researchers. D. polyandra, known as “Uncha” in Kaanju language, is used in Northern Kaanju Traditional Medicine for relief from pain associated with toothache and related ailments. The species has a restricted distribution in Cape York Peninsula and there has been no previous Western scientific investigation of its pharmacology or chemistry. Aim of the study: The current study investigates the anti-inflammatory effects of several extracts from D. polyandra. Materials and methods: Phytochemical screening was conducted using TLC. Anti-inflammatory effects of leaf extracts were determined using an acute mouse ear oedema model induced by croton oil and 12-o-tetradecanoylphorbol-13-acetate (TPA) chemical irritants. Results: Flavonoid and terpenoid secondary compounds were detected in leaf extracts of D. polyandra. Non-polar hexane and methylene chloride/methanol extracts showed potent inhibition of inflammation in TPA-induced mouse ear oedema by 72.12 and 79.81%, respectively, after 24h at 0.4mg/ear. Conclusion: In a mouse model of acute inflammation, this study revealed that leaf extracts of D. polyandra possess significant anti-inflammatory potential. These results contribute to a Western scientific understanding of the ethnopharmacological use of the plant in Northern Kaanju Medicine for reducing tooth-related pain. [Copyright &y& Elsevier]

1. In most cases, the most important determinant of wetland vegetation is the water regime. Although water regime is usually described and managed at the scale of whole wetlands, the patterning of vegetation is likely to be determined by water regimes that are experienced at much finer spatial scales. In this study, we assess the significance of internal heterogeneity in water regimes and the role that this heterogeneity plays in vegetation patterning. 2. The effects of water regime on wetland plant species richness and vegetation structure were studied at Dowd Morass, a 1500 ha, Ramsar-listed wetland in south-eastern Australia that is topographically heterogeneous. Data on plant variables and water depth were collected along 45 (50 m) transects throughout the wetland and related to water regimes assigned individually for each transect. Wetland plants were assigned to plant functional groups (PFG) that describe the response of plants to the presence or absence of water at different life stages. 3. The classification of water depth data indicated four distinct water regimes in the wetland that were differentiated primarily by the duration of the dry period. Representatives of all PFGs co-existed over small spatial scales where topographical variation was present, and the richness and cover of understorey species declined as transects became more deeply and permanently flooded. Some PFGs (e.g. amphibious fluctuation tolerator-low growing and amphibious fluctuation responder-morphologically plastic) were eliminated by extended periods of flooding, which increased the cover but not richness of submerged plants. Species richness and foliage projective cover declined as water regimes shifted from shallow and frequently exposed conditions to regimes typified by deeper and longer inundation. Cover of the structurally dominant woody species was compromised by deeply flooded conditions but vegetative regeneration occurred despite high water levels. 4. Internal topographical variation generates mosaics of water regimes at fine spatial scales that allow plant species with different water regime requirements to co-exist over small distances. Deep water and an absence of dry periods result in decreased cover of plants and an overall loss of species richness in the understorey. Water regimes are described that promote regeneration and cover of structurally dominant taxa and increased species richness in the understorey. The study demonstrates a strong association between vegetation and the diverse water regimes that exist within a single wetland, a pattern that will be useful for modelling the effects of modified water regimes on wetland vegetation. [ABSTRACT FROM AUTHOR]

Leaf reddening is well documented in terrestrial angiosperms, but has rarely been reported in seagrasses. In a survey of the world's six seagrass bioregions, we documented leaf reddening in 12 seagrass species from intertidal and shallow subtidal waters at 25 locations in the tropical Atlantic and tropical Indo-Pacific Oceans. Including additional observations of seagrasses with reddened leaves from Australia, the phenomenon is now documented in 15 seagrass species at 29 locations worldwide. Similar to terrestrial angiosperms, leaf reddening in seagrasses may relate to enhanced production of anthocyanins after exposure to one or more stressors. [ABSTRACT FROM AUTHOR]

Abstract: The decay rate of leaves of five Australian tree species, Acacia melanoxylon R. Br., Atherosperma moschatum Labill., Eucalyptus regnans F.Muell., Lomatia fraseri and Nothofagus cunninghamii (Hook.) Oerst., was quantified to determine whether differences in decay rates influence leaf fossilization potential. Decay rates were determined under 4 sets of conditions that mimicked the main ecological settings where a leaf could come to rest after abscission: the forest floor; buried in terrestrial forest sediments; the sediment–water interface of a stream or lake; and buried in stream sediments. Leaf physiochemisty was characterized to identify the chemical constraints that may affect decay rates, and leaf decay (measured as loss of mass and change in leaf lamella area) was examined to determine whether leaves lost area (a quantity often measured by palaeobotanists) at the same rate as they lost mass (the quantity often measured by limnologists). A. moschatum decayed rapidly regardless of treatment conditions, whilst N. cunninghamii not only decayed more slowly than the other taxa but decayed significantly more slowly when buried than when on the sediment surface. Differences in decay rates across the 5 species were similar when expressed as mass loss or as loss of leaf area, indicating that species that undergo rapid mass loss also undergo rapid area loss and thus become rapidly unrecognizable in the leaf fossil record. An important predictor of decay rates was lignin-to-nitrogen ratio; species with high lignin-to-nitrogen ratios had the lowest decay rates and, by implication, the best chances of entering the fossil record. Published leaf-decay rates in the soil ecology and limnological literature thus can be used to indicate which species could be over or under represented in the leaf fossil record using nearest living relative analysis; such an approach may enhance the accuracy of palaeobotanical reconstructions. [Copyright &y& Elsevier]

• Amino acid concentration and composition in xylem and phloem sap and in plant tissues are good markers of plant performance and general plant nitrogen (N)-supply. Here, we tested if amino acid pools in Eucalyptus regnans, growing in southeastern Australia were increased by understory acacias in 70-yr-old stands, and if xylem N-transport of temperate Acacia spp. differs from their tropical counterparts. • We analysed amino-N concentrations and composition in foliage, xylem and phloem. In a novel approach we coupled amino-N concentrations of xylem with long-term sap flow measurements to calculate total stand N-transport. • Xylem N-transport of E. regnans is largely based on amino compounds of the glutamate group (more than 90%). By contrast, Acacia spp. transport mainly aspartate group amino acids in xylem (up to 80%). Amino compound diversity and concentration in tissues and xylem and phloem sap were universally greater in acacias compared to eucalypts. Acacias investigated here can be classified as ‘amide transporters’. • We conclude that N-status and growth potential of aging E. regnans forest is not enhanced by a contribution of N from understory acacias, and that xylem N-transport in temperate Acacia spp. differs from acacias located in the tropics. [ABSTRACT FROM AUTHOR]

Photosynthetic rate per unit nitrogen generally declines as leaf mass per unit area (LMA) increases. To determine how much of this decline was associated with allocating a greater proportion of leaf nitrogen into cell wall material, we compared two groups of plants. The first group consisted of two species from each of eight genera, all of which were perennial evergreens growing in the Australian National Botanic Gardens (ANBG). The second group consisted of seven Eucalyptus species growing in a greenhouse. The percentage of leaf biomass in cell walls was independent of variation in LMA within any genus, but varied from 25 to 65% between genera. The nitrogen concentration of cell wall material was 0.4 times leaf nitrogen concentration for all species apart from Eucalyptus, which was 0.6 times leaf nitrogen concentration. Between 10 and 30% of leaf nitrogen was recovered in the cell wall fraction, but this was independent of LMA. No trade-off was observed between nitrogen associated with cell walls and the nitrogen allocated to ribulose 1·5-bisphosphate carboxylase/oxygenase (Rubisco). Variation in photosynthetic rate per unit nitrogen could not be explained by variation in cell wall nitrogen. [ABSTRACT FROM AUTHOR]

The differential flammability of individual plant species in landscape-scale fire behaviour is an important consideration, but one that is often overlooked. This is in part due to a relative dearth in the availability of plant flammability data. Here, we present a highly accurate predictive model of the likelihood of plant leaves entering flaming combustion as a function of leaf mass per area (LMA), leaf area (LA) and radiant heat flux using species of fire-prone dry sclerophyll forests of south-eastern Australia. We validated the performance of the model on two separate datasets, and on plant species not included in the model building process. Our model gives accurate predictions (75–84%) of leaf flaming with potential application in the next generation of fire behaviour models. Given the global wealth of species' data for LMA and LA, in stark contrast to leaf flammability data, our model has the potential to improve understanding of forest flammability in the absence of leaf flammability information. [ABSTRACT FROM AUTHOR]

We tested predictions of the relative changes in plant leaf traits in response to land uses in Australian eucalypt grassy ecosystems. Predictions were determined from responses observed in European landscapes in relation to disturbances associated with agricultural land uses. We measured specific leaf area (SLA) and leaf dry matter content (LDMC) across five land uses: reference sites (closest to pre-European state), native pastures (unfertilized), fertilized pastures, sown pastures (cultivated and fertilized) and enriched grassland (previously fertilized, no longer grazed). Leaves were expected to have higher SLA and lower LMDC at sites with increasing fertility and/or disturbance. The predictions were confirmed, with SLA increasing progressively in land uses associated with (1) grazing; (2) grazing and fertilization; (3) grazing, fertilization and cultivation. Values for LDMC were closely (but inversely) correlated with those of SLA. For both traits, there were relationships with available soil phosphorus but not with soil total nitrogen. The positive correlation of SLA with phosphorus was not evident above 30mgkg−1, the recommended level of phosphorus for improved pastures. Results confirm patterns of leaf-trait response to disturbance that reflect fundamental constraints to plant survival in habitats with different levels of resources and disturbances. A conservative strategy for low productivity undisturbed habitats is associated with low SLA and high dry matter content in contrast to fertile disturbed habitats which select for high SLA and low dry matter content. The changes in leaf traits across land uses resulted from species substitution rather than variation within species across sites, and most notably the replacement of native by annual exotic species as land use intensifies. Recommended fertilization rates for pasture production convert the ground layer to plants with soft, digestible leaves, that are responsive to fertilizer and desirable for livestock production. However, fertilization also drastically reduces the diversity of native plants and annual plants tend to dominate. The trade-off associated with high production includes increased vulnerability to soil erosion, due to reduced plant cover and low persistence of cover. If alternative ecosystem values such as erosion control, water quality, salinity control and biodiversity persistence are required, incentives may be needed to offset the loss of production that can be gained from fertilizer application. [Copyright &y& Elsevier]

Leaf carbon isotope discrimination (δ13C) was widely considered to directly reflect the rainfall environment in which the leaf developed, but recent observations have queried this. The relationship between δ13C and rainfall was explored in Eucalyptus species growing along a rainfall gradient in Australia. The leaves of 43 species of Eucalyptus and the closely related Corymbia species produced in 2003 were sampled in September 2004 at 50 sites and grouped into 15 locations along a rainfall gradient in southwest Western Australia. At 24 sites, the same species and same trees were sampled as in a study in September 2003 when leaves produced in 2002 were sampled. The rainfall in 2004 was on average 190 mm (range 135–270 mm) higher at all locations than in 2003. In the leaves sampled in 2004, the mean carbon isotope discrimination (δ13C) across the 15 locations decreased 2.9‰ per 1000 mm of rainfall, the specific leaf area (SLA) increased by 2.9 m2 kg−1 per 1000 mm of rainfall and the nitrogen (N) content decreased by 1.56 g m−2 per 1000 mm of rainfall. In contrast, a comparison between the leaves produced in the drier 2002 year compared with the wetter 2003 year showed that there was a strong correlation (r2= 0.85) between the SLA values between years and a trend for higher values with increasing SLA, but the values of δ13C were on average only 0.38‰ lower (more negative) at all locations in the wetter year, equivalent to a decrease of 2.0‰ per 1000 mm of rainfall. The results suggest that while there may be constitutive differences in leaf morphology, SLA and N content per unit area, increasing rainfall or cloudiness associated with higher rainfall increases SLA and decreases N content per unit area. We conclude that rainfall does not directly influence δ13C, but induces leaf morphological and physiological changes that affect the resultant δ13C. [ABSTRACT FROM AUTHOR]

Previous research on P leaf analysis for detecting deficiencies in cotton (Gossypium hirsutum L.) has not considered temperature as a determining factor. This is despite correlations between leaf P content and temperature being observed in other crops. As part of research into a new cotton farming system for the semi-arid tropics of Australia, we conducted two P fertiliser rate experiments on recently cleared un-cropped (bicarbonate P < 5 mg kg- 1) and previously cropped (bicarbonate P 26 mg kg- 1) soil. They aimed to develop P requirements and more importantly to determine if temperature affects the leaf P concentrations used to diagnose P deficiencies. In 2002, optimal yield on un-cropped, low P soil was achieved with a 60 kg P ha- 1 rate. In 2003, residual P from the 40 kg P ha- 1 treatment produced optimal yield. On cropped, high P soil there was no yield response to treatments up to 100 kg P ha- 1. On low P soil, a positive correlation was observed between P concentration in the youngest fully-unfurled leaf (YFUL), fertiliser rate, and mean diurnal temperature in the seven days prior to sampling. On high P soil, a positive correlation was observed between the YFUL and mean diurnal temperature however there was no correlation with fertiliser rate. These results show that YFUL analysis can be used to diagnose P deficiencies in cotton, provided the temperature prior to sampling is considered. [ABSTRACT FROM AUTHOR]

The importance of litter in regulating ecosystem processes has long been recognised, with a growing appreciation of the differential contribution of various functional plant groups. Despite the ubiquity of mistletoes in terrestrial ecosystems and their prominence in ecological studies, they are one group that have been overlooked in litter research. This study evaluated the litter contribution from a hemiparasitic mistletoe, Amyema miquelii (Lehm. ex Miq.) Tiegh., in an open eucalypt forest ( Eucalyptus blakelyi, E. dwyeri and E. dealbata), at three scales; the forest stand, single trees and individual mistletoes. Litter from mistletoes significantly increased overall litterfall by up to 189%, the amount of mistletoe litter being proportional to the mistletoe biomass in the canopy. The high litter input was due to a much higher rate of mistletoe leaf turnover than that of host trees; the host litterfall and rate of leaf turnover was not significantly affected by mistletoe presence. The additional litter from mistletoes also affected the spatial and temporal distribution of litterfall due to the patchy distribution of mistletoes and their prolonged period of high litterfall. Associated with these changes in litterfall was an increase in ground litter mass and plant productivity, which reflects similar findings with root-parasitic plants. These findings represent novel mechanisms underlying the role of mistletoes as keystone resources and provide further evidence of the importance of parasites in affecting trophic dynamics. [ABSTRACT FROM AUTHOR]

Many theoretical and applied studies have demonstrated that the anisotropic reflectance of the land surface is determined by the structural and optical properties of the land surface. The Multi-angle Imaging SpectroRadiometer (MISR) measures the anisotropic reflectance of the land surface thus has the potential to improve the operational mapping of canopy attributes in Queensland, one of the largest states in Australia. The aim of this study was to assess the relationship between foliage projective cover (FPC) and the shape of the bidirectional reflectance distribution function (BRDF) for a mixed grassland/woodland ecosystem, the Southern Brigalow Belt Biogeographic Region. A practical approach for deriving the surface bidirectional reflectance factor (BRF) from MISR “Local" mode data using existing MISR products is presented. The BRDF typology of the land surface was determined using shape parameters derived from inversion of the linear Ross–Thick Li–Sparse Reciprocal and the non-linear Rahman–Pinty–Verstraete (RPV) models against a time series of MISR “Local" mode surface BRF data. Following an evaluation of the models inversion error, the RPV model was examined for correlation with FPC, a canopy attribute routinely derived from Landsat data in Queensland. Our empirical analyses showed the MISR derived RPV model parameters were qualitatively related to spatial and temporal variations in vegetation structure in Queensland and the k parameter contained information independent of FPC. These results are consistent with published findings from other regions. [Copyright &y& Elsevier]

Two models were evaluated for their ability to estimate land surface evaporation at 16-day intervals using MODIS remote sensing data and surface meteorology as inputs. The first was the aerodynamic resistance–surface energy balance model, and the second was the Penman–Monteith (P–M) equation, where the required surface conductance is estimated from remotely-sensed leaf area index. The models were tested using 3 years of evaporation and meteorological measurements from two contrasting Australian ecosystems, a cool temperate, evergreen Eucalyptus forest and a wet/dry, tropical savanna. The aerodynamic resistance–surface energy balance approach failed because small errors in the radiative surface temperature translate into large errors in sensible heat, and hence into estimates of evaporation. The P–M model adequately estimated the magnitude and seasonal variation in evaporation in both ecosystems (RMSE=27 W m−2, R 2 =0. 74), demonstrating the validity of the proposed surface conductance algorithm. This, and the ability to constrain evaporation estimates via the energy balance, demonstrates the superiority of the P–M equation over the surface temperature-based model. There was no degradation in the performance of the P–M model when gridded meteorological data at coarser spatial (0. 05°) and temporal (daily) resolution were substituted for locally-measured inputs. The P–M approach was used to generate a monthly evaporation climatology for Australia from 2001 to 2004 to demonstrate the potential of this approach for monitoring land surface evaporation and constructing monthly water budgets from 1-km to continental spatial scales. [Copyright &y& Elsevier]

The deep lateritic earths that cap the serpentinite outcrop in the Rockhampton – Marlborough area on the Tropic of Capricorn in Central Queensland have been eroded to expose the underlying ultramafic rock. Water-holding capacity of these nutrient-poor soils increases in a gradient from the skeletal soils to the deep lateritic earths and results in a continuum of structural formations from open-woodland to woodland to open-forest. A couple of closed-forest (rainforest) stands have developed where seepage into Marlborough Creek occurs throughout the year. Aerodynamic fluxes (frictional, thermal and evaporative) in the atmosphere as it flows over and through the vegetation influence the annual foliage growth in all strata in the continuum from skeletal soils to deep lateritic earths. The lateral growth of each plant is abraded so that the sum of the foliage projective covers of overstorey (FPCo) and understorey (FPCu) strata – that is Σ(FPCo + FPCu) – remains constant throughout the serpentinite soil catena. As more water becomes available in the soil catena, the mineral nutrient levels in overstorey leaves increase, making developing leaves more vulnerable to insect attack. Although the number of leaves produced annually on each vertical foliage shoot in the overstorey increases along the soil-water gradient, Σ(FPCo + FPCu) remains constant in all stands. The carbon isotope ratios (a measure of stomatal resistance) and leaf specific weights (LSWs) (a measure of the proportion of structural to cytoplasmic content in a leaf) of overstorey and understorey strata, however, are constant throughout the continuum. The well-watered rainforest pockets – where seepage occurs – form the end point of this serpentinite continuum. LSWs and carbon isotope ratios of the canopy trees are similar to those in the sheltered understorey in the eucalypt communities. A gradient of foliage attributes is observed from evergreen canopy trees (12 m) to subshrubs (2 m) in the sunlit life forms that compose the complex structure of the rainforest stands in the humid to subhumid climate of Central Queensland. As alpha diversity (number of species per hectare) is correlated with annual shoot growth per hectare, species richness along the serpentinite continuum is almost half that of nearby plant communities on medium-nutrient soils. The one to two eucalypt species per hectare are about a tenth of the number recorded on adjacent medium-nutrient soils. [ABSTRACT FROM AUTHOR]

Although adult female embiids (Order Embiidina) superficially lack morphological diversity, their variety of habitats may impose distinct selective pressures on behavior, such as their use of silk and their tendency to aggregate. For example, where silk serves as a primary defense from environmental threats, coloniality might be adaptive. The cost of production or spinning might also prompt them to share silk. These ideas were tested in laboratory trials involving three species of embiids with different lifestyles: an arboreal species (Antipaluria urichi (Saussure) from a neotropical rain forest, a species (Notoligotoma hardyi (Frederichs) that dwells on surfaces of granite outcrops in Australia, and another Australian species (Australembia incompta Ross) that stitches leaf litter together. The cost of spinning silk was analyzed by recording CO2 output in the short term during spinning and by measuring performance in long-term trials where embiids were forced to repeatedly replace their silk. Their subsequent development or reproductive output was scored. Overall, the cost of spinning was relatively low. However, the tendencies to spin and to aggregate varied in a manner related to how silk is used in the field. As such, the more exposed the embiid is to the elements, as for the two species that spin on surfaces, the more silk they spun and the more likely they settled near a neighbor. In contrast, the embiid that used dead leaves (not silk) as walls for their abodes produced scant silk and showed little tendency to aggregate. [ABSTRACT FROM AUTHOR]

Sclerophylly is a common feature of vegetation on infertile soils, and its adaptive significance has been linked to nutrient-use efficiency by protection of leaves to maximise carbon gain. However, there has been little investigation of how the leaf mechanical properties that contribute to the phenomenon of sclerophylly vary along nutrient gradients. In this paper, we investigate how leaf mechanical properties vary among plants on three contrasting soil types (grey sand, laterite soil, and soil overlying dolerite) in a Mediterranean climate in southwestern Australia. Most species were sclerophyllous, but there was 5-fold variation in leaf mass per unit area (LMA) and 17- to 473-fold variation in mechanical properties among species. Species growing on laterite and/or sand (low-nutrient soils) had higher punch strength, work (a measure of toughness) to punch, specific (per unit leaf thickness) work to punch, work to shear, specific work to shear, and flexural stiffness ( EI W) than those on dolerite soils (higher in nutrients). There were few differences in mean values of leaf mechanical properties between the two low-nutrient soils, possibly because the lower concentration of nutrients in the sand is balanced by the greater soil volume than the laterite soil (higher concentration of nutrients, but shallower). There were also few differences in leaf properties between plants of the same species growing on contrasting soil types. There was some variation among sclerophyllous species in their mechanical characteristics, but overall, EI W provided the strongest contribution to sclerophylly, explaining up to 81% of the variation in LMA. There was no evidence of differences among soil types in the relationships of mechanical properties with LMA, and therefore, no evidence of variation in the mechanical constitution of sclerophylly among soil types. [ABSTRACT FROM AUTHOR]

A new species of Frankliniella Karny, probably introduced to Australia from the Caribbean area, is described here as causing feeding damage to the young leaves of Lantana in south-eastern Queensland and northern New South Wales. The new species is unusual within this large, primarily Neotropical genus, in that it feeds only on leaves, not in flowers, and that adult females are either apterous or fully winged. Only 10 of the 160 described species of Frankliniella are known to exhibit wing reduction, and notes are given on these together with notes on the seven species of the genus that are not endemic to the New World. Life history studies, including sex and morph ratios, indicate that egg to adult can require as little as 12 d, but despite breeding well in greenhouses, the species is not known to develop large populations in the field in Australia. [ABSTRACT FROM AUTHOR]

Examines the characteristics of Licuala ramsayi or fan-palm found in Australia. Background on the taxonomic history of the Australian fan-palm; Stem height; Description of its leaves; Information on varieties of Licuala ramsayi.

Uncertainties regarding the relationships between leaf and root traits have impeded an integrated understanding of plant evolution and the efficient parameterization of ecosystem models. We measured key root and leaf traits of grasses from 77 sites in four grassland regions of the world (New Zealand, Australia, South Africa, North America). Within each region, the relationships among leaf traits paralleled those among root traits. Plants with low root or leaf N concentrations had roots or leaves with high tissue density, high lignin concentrations, low amount of mass that was soluble in a neutral detergent solution, large diameter/thickness, and were less enriched in 15N. Yet, whether comparing plants within a region or among all four regions, there was little relationship between root traits and leaf traits, except for a positive relationship between root and leaf N concentration and between root and leaf δ15N. At the global scale, factors such as soil freezing and the type of nutrient limitation appear to determine relationships among leaves and roots. C4 grasses not only had lower leaf N concentrations than C3 grasses but also lower root N concentrations. When compared at the same root N concentration, C4 grasses had greater leaf N concentrations than C3 grasses. [ABSTRACT FROM AUTHOR]

1. An individual evergreen leaf in the northern Australian savanna biome experiences seasonal extremes in rainfall, raising questions of whether there is a corresponding shift in the physiology of these leaves, and whether estimates of leaf function for the biome differ between wet and dry seasons.2. A range of leaf attributes was measured for 21 tree species in four contrasting habitats during the wet season, and again during the dry season for the 14 species that retained leaves.3. The 14 leaf-retaining species showed decreases in assimilation rates, foliar saturated water content and chlorophyll content, and increases in leaf mass per area and leaf density between wet and dry seasons. Species means were strongly correlated between seasons for attributes other than assimilation and stomatal conductance.4. Seasonal variation in CO2 assimilation rates was larger in non-Myrtaceous species than in the leaf-retaining Myrtaceous species that largely dominate the biome, and also varied considerably among the four habitats, which had different edaphic conditions. Assimilation per unit mass decreased between the wet and dry seasons by only 5% in theMelaleucaswamp and 17% in theEucalyptusopen forest, compared with 47% in the dry monsoon forest and 57% in the mixed woodland.5. Biome means differed between seasons because wet-season means included measurements of fully deciduous species which tended to have large, thin, nitrogen-rich leaves.Functional Ecology(2004)18, 707–718 [ABSTRACT FROM AUTHOR]

The leaf oils of the Australian members of the genus Pseuduvaria have been examined. Both P. mulgraveana var. mulgraveana and P. mulgraveana var. glabrescens showed extremes in oil composition, with elemicin (87%) and methyl eugenol (61%) being the principal components. Pseuduvaria villosa possessed a sesquiterpenic oil in which the major components were β-caryophyllene (3-13%) and α-copaene (4-11%). In the oil from P. froggattii, the principal components were caryophyllene oxide (2-22%), a fourth dihydroagarofuran isomer (froggatt ether) (0.1-18%), spathulenol (9-18%) and a sesquiterpene alcohol C15H260 (t-20%), while in P. hylandii the major components were β-caryophyllene (22-28%), α-himachalene (2-10%) and α-humulene (8-9%). [ABSTRACT FROM AUTHOR]

The leaf oils of the Australian members of the genus Podocarpus have been analyzed using CC and GC/MS. All species produced poor yields of oils (0.01-0.3%). The leaf oil of P. dispermus contained isopimara-9(11),15-diene (10.3%) and a C20H32 (B) compound (12.7%) as principal components. Bicyclogermacrene (57%) was the principal component of P. drouynianus. Podocarpus elatus gave an oil in which α-pinene, β-caryophyllene and bicyclogermacrene were the principal components. Bicyclogermacrene (27-44%), germacrene D (4-11%) and spathulenol (3-11%) were the principal components of the oil from P. grayae. Podocarpus lawrencei was one of only two Australian Podocarpus species to produce an oil (0.1-0.6%), which contained significant amounts of diterpenes. The main components were α-pinene (14-18%), β-caryophyllene (3-15%), spathulenol (0.8-19%), rimuene (0.2-30%), sandarocopimara-8(14),15-diene (0.1-20%) and beyerene (7-9%). Podocarpus smithii produced a complex sesquiterpenic oil in which α-copaene (4-8%), β-caryophyllene (5%) and δ-cadinene (9-11%) were the main components. Limonene (13-16%), bicyclogermacrene (15-18%) and viridiflorol (16-18%) were the main components of P. spinulosus oil. [ABSTRACT FROM AUTHOR]