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Summary One of the foremost technical issues addressed in reintroduction and restoration projects is the feasibility of establishing living plants. To advance the recovery process, the germination requirements of 201 threatened Western Australian seed-bearing taxa representing a range of life forms, families and ecophysiological characteristics were studied. Procedures used to stimulate germination in otherwise dormant seed involved pretreatment using thermal shock, scarification, seed coat removal, soaking in an aqueous smoke solution and/or additions of the growth hormone gibberellic acid (GA3 ). Sixty-one taxa germinated under the basic trial conditions of light (12- h photoperiod), temperature (constant 15°C) and moisture, without additional pretreatments. These taxa were generally those with canopy-stored seeds in the families Proteaceae and Casuarinaceae, and small-seeded taxa in Myrtaceae. Taxa with soil-stored seeds required single or multiple cues to stimulate germination. Seeds in the families Fabaceae and Mimosaceae were dependent on cracking of the seed coat, mechanically through nicking of the testa or through thermal shock, as were several non-leguminous species of the Sterculiaceae and Liliaceae. Complete or partial removal of seed coats, in conjunction with GA3 enhanced germination percentage in some taxa of the Myoporaceae, Lamiaceae and Myrtaceae. Application of GA3 also enhanced germination percentage in members of the Epacridaceae. Several taxa previously stimulated by aqueous smoke solutions were equally responsive to additions of GA3 after complete seed coat removal. In general, species with seed weights greater than 10 mg germinated better under a range of conditions than those with lighter seeds. There was no difference in germinability between resprouter and seeder species, and no obvious relationship between seed weight and germination rate. In the light of previous studies these results... [ABSTRACT FROM AUTHOR]

Myoporum platycarpum R. Br. (Myoporaceae) is widely distributed through semi-arid New South Wales, South Australia, Western Australia and Victoria, where it occurs as an upper-storey dominant or co-dominant tree over chenopod shrublands. Previous studies have concluded that the seedlings and juveniles of many shrubs and trees, including M. platycarpum, are selectively grazed by sheep and rabbits, which threatens their long-term survival in rangelands. The aim of this study was to assess the survivorship of M. platycarpum seedlings grazed by sheep and rabbits in a rangeland setting. Seedlings of M. platycarpum were raised in the greenhouse and planted in the field and individually fenced to allow or prevent access by various herbivores. Over 1 year, the frequency of grazing and size of canopy was recorded. A flexible mixed model incorporating cubic smoothing splines was used to describe the relationship between change in canopy volume over time, fixed effects (exclosure type, time, rainfall and egesta weights) and random variability among plants, replicates and sites. The mixed models showed that there were no significant differences in canopy volume over time between sheep and rabbit-proof exclosures, indicating that rabbits were not significantly affecting the seedlings, browsing only five of those available to them, of which three survived. Large herbivores (sheep and/or kangaroos) grazed un-caged seedlings, resulting in significantly smaller canopy volumes, and higher death rates (80%). Although supplementary irrigation was applied, background losses due to desiccation in caged seedlings were up to 50%. [ABSTRACT FROM AUTHOR]

Aim We evaluated how an elevation gradient affects: (1) the availability of food required by a specialist seed-eater, Loxioides bailleui Oustalet (Drepanidinae), or palila, and hence the distribution of this endangered Hawaiian bird, and (2) the distribution of alien threats to Loxioides populations, their primary foods, and their dry-forest habitat, and hence strategies for their conservation. Location We worked throughout the subalpine forest that encircles Mauna Kea Volcano, Hawai'i Island, but we focused our studies mainly on the western slope between 2000 and 3000 m elevation, where the gradient of elevation was greatest and palila were most abundant. Methods We determined phenology and productivity patterns of the endemic dry-forest tree species, Sophora chrysophylla (Salisb.) Seem. (Fabaceae), or mamane, which provides Loxioides with most of their food, and another common endemic tree, Myoporum sandwicense A. Gray (Myoporaceae), or naio, which provides some resources, along a 786-m elevation gradient at monthly intervals for 10 years (Sophora only). We also determined the availability each month of moth larvae (Lepidoptera) for that were important in the diet of nestling and adult palila. In addition, we documented the incidence of parasitism on moth larvae by several wasp (Hymenoptera) and fly (Diptera) species, and we determined the distribution of predatory wasps and ants (Hymenoptera), which potentially threaten insect prey of birds. Percentage cover of alien grass species that pose fire threats in palila habitat and other weeds were assessed during one survey. Small mammal abundance and distribution were determined by trapping during three (rodent) or five (carnivore) surveys. Results Sophora flower and seed (pod) availability varied predictably along the elevation gradient, with about 4 months separating peaks in reproduction at high and low elevations. This, together with highly variable production of flowers and pods within elevation strata,... [ABSTRACT FROM AUTHOR]

Summary: The figwort family, Scrophulariaceae, comprises c. 2000 species whose evolutionary relationships at the tribal level have proven difficult to resolve, hindering our ability to understand their origin and diversification.We designed a specific probe kit for Scrophulariaceae, targeting 849 nuclear loci and obtaining plastid regions as by‐products. We sampled c. 87% of the genera described in the family and use the nuclear dataset to estimate evolutionary relationships, timing of diversification, and biogeographic patterns.Ten tribes, including two new tribes, Androyeae and Camptolomeae, are supported, and the phylogenetic positions of Androya, Camptoloma, and Phygelius are unveiled. Our study reveals a major diversification at c. 60 million yr ago in some Gondwanan landmasses, where two different lineages diversified, one of which gave rise to nearly 81% of extant species. A Southern African origin is estimated for most modern‐day tribes, with two exceptions, the American Leucophylleae, and the mainly Australian Myoporeae. The rapid mid‐Eocene diversification is aligned with geographic expansion within southern Africa in most tribes, followed by range expansion to tropical Africa and multiple dispersals out of Africa.Our robust phylogeny provides a framework for future studies aimed at understanding the role of macroevolutionary patterns and processes that generated Scrophulariaceae diversity. This article is part of the Special Collection 'Global plant diversity and distribution'. See https://www.newphytologist.org/global-plant-diversity for more details. [ABSTRACT FROM AUTHOR]

The coastal heathlands of Northwest Europe are highly valued cultural landscapes, that are critically endangered due to land use and climatic changes, such as increased frequency and severity of drought events. Our study is the first to assess how the germination and early seedling growth of Calluna vulgaris respond to drought. In a factorial design field experiment, we exposed maternal plants to three in‐situ drought treatments (control, 60%, 90% roof coverage), across three successional stages after fire (pioneer, building, mature), and two regions (60°N, 65°N). Seeds from 540 plants within the experiment were, weighed, and exposed to five water potentials, ranging from −0.25 to −1.7 MPa, in a growth chamber experiment. We recorded germination (percentage, rate), seedling growth (above‐ vs. belowground allocation), and seedling functional traits (specific leaf area [SLA], specific root length [SRL]). Overall variation in germination between regions, successional stages, and maternal drought treatments was largely mediated by variation in seed mass. Plants from the northernmost region had higher seed mass and germination percentages. This is indicative of higher investment in seeds, likely linked to the populations' absence of vegetative root sprouting. Seeds from the mature successional stage germinated to lower final percentages than those from earlier successional stages, especially when the maternal plants had been exposed to drought (60% and 90% roof coverage). Exposure to reduced water availability decreased germination percentage and increased the time to 50% germination. Seedlings fully developed in the range −0.25 to −0.7 MPa, with increased root:shoot and lower SRL during reduced water availability, suggesting a resource‐conservative response to drought during the early stages of development. Our results thus suggest a sensitivity to drought during the germination and seedling life‐history stages that may reduce Calluna's ability to re‐establish from seeds as the incidence and severity of droughts are projected to increase under future climates. [ABSTRACT FROM AUTHOR]

Background: The existing drug treatments for trypanosomiases are limited and suffer from shortcomings due to their toxicity and the emergence of resistant parasites. Developing anti‐trypanosomal compounds based on natural products is a promising way of fighting trypanosomiases. Objectives: This study aims to identify through scientific review a large variety of medicinal plants (anti‐trypanosomal) used worldwide and scientifically shown to display anti‐trypanosomal effects. Methods: To collect data, the anti‐trypanosomal activities of Africa, Asia, the Middle East, South America, North America, Europe and Oceania medicinal plants have been checked by considering the published paper. Results: Based on collected data, 77 natural molecules were reported in the literature. Of which 59 were from the African region, 11 from Asia, 3 from Europe and 4 from Latin America. These active components belong to alkaloids, triterpenoids, lactone, quinoids, flavonoids, iridoids, lignans, steroids, lipids, oxygenated heterocycles, benzenoids, proteins, coumarins, phenylpropanoids and peptides. We also specified the prosperous plants with unique anti‐trypanosomal activities. Conclusions: However, there is a need for further studies on the ability of the isolated compounds to ameliorate the trypanosome‐induced pathological alterations and also the elucidation of their modes of actions and activities against other trypanosome species. [ABSTRACT FROM AUTHOR]

SUMMARY: In a cross‐continental research initiative, including researchers working in Australia and Denmark, and based on joint external funding by a 3‐year grant from the Novo Nordisk Foundation, we have used DNA sequencing, extensive chemical profiling and molecular networking analyses across the entire Eremophila genus to provide new knowledge on the presence of natural products and their bioactivities using polypharmocological screens. Sesquiterpenoids, diterpenoids and dimers of branched‐chain fatty acids with previously unknown chemical structures were identified. The collection of plant material from the Eremophila genus was carried out according to a 'bioprospecting agreement' with the Government of Western Australia. We recognize that several Eremophila species hold immense cultural significance to Australia's First Peoples. In spite of our best intentions to ensure that new knowledge gained about the genus Eremophila and any potential future benefits are shared in an equitable manner, in accordance with the Nagoya Protocol, we encounter serious dilemmas and potential conflicts in making benefit sharing with Australia's First Peoples a reality. [ABSTRACT FROM AUTHOR]

This account presents information on all aspects of the biology of Salvia pratensis L. (Meadow Clary) that are relevant to understanding its ecological characteristics and behaviour. The main topics are presented within the standard framework of the Biological Flora of the British Isles: distribution, habitat, communities, responses to biotic factors, responses to environment, structure and physiology, phenology, floral and seed characters, herbivores and disease, history and conservation.Salvia pratensis is an erect, rosette‐forming, perennial herb with a broad native distribution covering much of Europe—from the British Isles, Spain and Morocco in the west, across Europe into Asia, as far east as the Urals. In the British Isles, the species is nationally scarce, confined to a few south‐ to west‐facing sites with calcareous soils in Southern England and one site in Wales. It is predominately found in unimproved pasture, hay meadows and grassy verges, but can occur on the fringes of scrub or woodland. Although the species is abundant in central Europe, changes to land management since the mid‐20th century have resulted in fragmented and threatened populations in several European countries. It is cultivated as an ornamental, as is S. × sylvestris, the hybrid with S. nemorosa.Populations are typically gynodioecious, having both female (male‐sterile) and hermaphrodite individuals at variable proportions. The species has a mixed mating system and is self‐compatible via insect pollination, but predominantly outcrosses. Honeybees and bumblebees are abundant pollinators, but a diverse range of bee species and other insect species visit S. pratensis flowers. Inbreeding depression has been documented, presenting a conservation concern for small, fragmented populations.The species is the focus of conservation efforts and has been reintroduced to sites where it had become locally extinct in Britain. To sustain favourable habitat, site management should maintain low soil nutrient levels, and prevent scrub encroachment and the dominance of coarse grasses. The removal of sward by hay cutting or grazing after plants have flowered and set seed is advised, in addition to maintaining a degree of disturbance to provide bare patches of soil for seedling recruitment. [ABSTRACT FROM AUTHOR]

SUMMARY: Eremophila is the largest genus in the plant tribe Myoporeae (Scrophulariaceae) and exhibits incredible morphological diversity across the Australian continent. The Australian Aboriginal Peoples recognize many Eremophila species as important sources of traditional medicine, the most frequently used plant parts being the leaves. Recent phylogenetic studies have revealed complex evolutionary relationships between Eremophila and related genera in the tribe. Unique and structurally diverse metabolites, particularly diterpenoids, are also a feature of plants in this group. To assess the full dimension of the chemical space of the tribe Myoporeae, we investigated the metabolite diversity in a chemo‐evolutionary framework applying a combination of molecular phylogenetic and state‐of‐the‐art computational metabolomics tools to build a dataset involving leaf samples from a total of 291 specimens of Eremophila and allied genera. The chemo‐evolutionary relationships are expounded into a systematic context by integration of information about leaf morphology (resin and hairiness), environmental factors (pollination and geographical distribution), and medicinal properties (traditional medicinal uses and antibacterial studies), augmenting our understanding of complex interactions in biological systems. Significance Statement: The chemical space of the Australian genus Eremophila, used in traditional medicine by Indigenous Australians, is explored using a novel large‐scale computational metabolomics‐based molecular network approach combined with phylogenetic analyses to provide a detailed overview of the complex metabolite diversity and chemo‐evolutionary relationships present. Integration of information about leaf morphology (resin and hairiness), environmental factors (pollination and biogeographical distribution), and medicinal properties (Aboriginal uses and antibacterial studies) brings the chemical information into a systematic context. [ABSTRACT FROM AUTHOR]

SUMMARY: Serrulatane diterpenoids are natural products found in plants from a subset of genera within the figwort family (Scrophulariaceae). Many of these compounds have been characterized as having anti‐microbial properties and share a common diterpene backbone. One example, leubethanol from Texas sage (Leucophyllum frutescens) has demonstrated activity against multi‐drug‐resistant tuberculosis. Leubethanol is the only serrulatane diterpenoid identified from this genus; however, a range of such compounds have been found throughout the closely related Eremophila genus. Despite their potential therapeutic relevance, the biosynthesis of serrulatane diterpenoids has not been previously reported. Here we leverage the simple product profile and high accumulation of leubethanol in the roots of L. frutescens and compare tissue‐specific transcriptomes with existing data from Eremophila serrulata to decipher the biosynthesis of leubethanol. A short‐chain cis‐prenyl transferase (LfCPT1) first produces the rare diterpene precursor nerylneryl diphosphate, which is cyclized by an unusual plastidial terpene synthase (LfTPS1) into the characteristic serrulatane diterpene backbone. Final conversion to leubethanol is catalyzed by a cytochrome P450 (CYP71D616) of the CYP71 clan. This pathway documents the presence of a short‐chain cis‐prenyl diphosphate synthase, previously only found in Solanaceae, which is likely involved in the biosynthesis of other known diterpene backbones in Eremophila. LfTPS1 represents neofunctionalization of a compartment‐switching terpene synthase accepting a novel substrate in the plastid. Biosynthetic access to leubethanol will enable pathway discovery to more complex serrulatane diterpenoids which share this common starting structure and provide a platform for the production and diversification of this class of promising anti‐microbial therapeutics in heterologous systems. Significance Statement: Serrulatane diterpenoids are natural products known for their anti‐microbial activities, and access is currently limited to chemical synthesis or extraction from natural sources. Here we report the full biosynthetic pathway to the serrulatane diterpenoid leubethanol from Leucophyllum frutescens, which is active against multi‐drug‐resistant tuberculosis. The pathway involves an uncommon diterpene precursor, and further steps yield the archetypal diterpenoid structure shared across nearly all serrulatanes, which may enable development of a new class of anti‐microbial therapeutics. [ABSTRACT FROM AUTHOR]

Abstract: The ideal species for green or vegetated roofs should have high water use after rainfall to maximize stormwater retention but also survive periods with low water availability in dry substrates. Shrubs have great potential for green roofs because they have higher rates of water use, and many species are also drought tolerant. However, not all shrub species will be suitable and there may be a trade‐off between water use and drought tolerance. We conducted a glasshouse experiment to determine the possible trade‐offs between shrub water use for stormwater management and their response to drought conditions. We selected 20 shrubs from a wide range of climates of origin, represented by heat moisture index (HMI) and mean annual precipitation (MAP). Under well‐watered (WW) and water‐deficit (WD) conditions, we assessed morphological responses to water availability; evapotranspiration rate (ET) and midday water potential (ΨMD) were used to evaluate species water use and drought response. In response to WD, all 20 shrubs adjusted their morphology and physiology. However, there were no species that simultaneously achieved high rates of water use (high ET) under WW and high drought tolerance (low ΨMD) under WD conditions. Although some species which had high water use under WW conditions could avoid drought stress (high ΨMD). Water use was strongly related to plant biomass, total leaf area, and leaf traits (specific leaf area [SLA] and leaf area ratio [LAR]). Conversely, drought response (ΨMD) was not related to morphological traits. Species’ climate of origin was not related to drought response or water use. Drought‐avoiding shrubs (high ΨMD) could optimize rainfall reduction on green roofs. Water use was related to biomass, leaf area, and leaf traits; thus, these traits could be used to assist the selection of shrubs for stormwater mitigation on green roofs. The natural distribution of species was not related to their water use or drought response, which suggests that shrubs from less arid climates may be suitable for use on green roofs. Selecting species based on traits and not climate of origin could both improve green roof performance and biodiversity outcomes by expanding the current plant palette. [ABSTRACT FROM AUTHOR]

Plant height and growth are fundamental to the understanding of species ecological strategies, to the description and prediction of ecosystem dynamics and to vegetation management, such as plant species' fire responses. However, a convenient way to characterize the height growth strategies for multiple species have been elusive. We examine the height growth trajectories in 18 woody plant species in a light-saturated, fire-prone, semi-arid environment as well as the influence of functional traits on those trajectories. We test trait-growth relationships by examining 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. Woody plant species in the semi-arid mallee exhibit fast growth trajectories. Small seeded species were likely to be the fastest to reach maximum height, while large-seeded species with high leaf nitrogen were likely the slowest. Tall species had low stem densities and tended to have low specific leaf area. We modelled plant growth using a hierarchical multi-species model that formally incorporates plant functional traits as species-level predictors of growth, which provides a method for predicting species height growth strategies as a function of their traits. We extend this approach by using the modelled relationships from our trait-growth model to predict: growth trajectories of species with limited data; real species with only trait data and; hypothetical species based only on trait coordination. We hope this highlights the potential to use trait information for ecological inference and to generate predictions that could be used for management. [ABSTRACT FROM AUTHOR]

The interaction between floral traits and reproductive isolation is crucial to explaining the extraordinary diversity of angiosperms. Heterostyly, a complex floral polymorphism that optimizes outcrossing, evolved repeatedly and has been shown to accelerate diversification in primroses, yet its potential influence on isolating mechanisms remains unexplored. Furthermore, the relative contribution of pre- versus postmating barriers to reproductive isolation is still debated. No experimental study has yet evaluated the possible effects of heterostyly on pre- and postmating reproductive mechanisms. We quantify multiple reproductive barriers between the heterostylous Primula elatior (oxlip) and P. vulgaris (primrose), which readily hybridize when co-occurring, and test whether traits of heterostyly contribute to reproductive barriers in unique ways. We find that premating isolation is key for both species, while postmating isolation is considerable only for P. vulgaris; ecogeographic isolation is crucial for both species, while phenological, seed developmental, and hybrid sterility barriers are also important in P. vulgaris, implicating sympatrically higher gene flow into P. elatior. We document for the first time that, in addition to the aforementioned species-dependent asymmetries, morph-dependent asymmetries affect reproductive barriers between heterostylous species. Indeed, the interspecific decrease of reciprocity between high sexual organs of complementary floral morphs limits interspecific pollen transfer from anthers of short-styled flowers to stigmas of long-styled flowers, while higher reciprocity between low sexual organs favors introgression over isolation from anthers of long-styled flowers to stigmas of short-styled flowers. Finally, intramorph incompatibility persists across species boundaries, but is weakened in long-styled flowers of P. elatior, opening a possible backdoor to gene flow through intramorph pollen transfer between species. Therefore, patterns of gene flow across species boundaries are likely affected by floral morph composition of adjacent populations. To summarize, our study highlights the general importance of premating isolation and newly illustrates that both morph- and species-dependent asymmetries shape boundaries between heterostylous species. [ABSTRACT FROM AUTHOR]

Variation in mutualistic and antagonistic interactions are important sources of variation in population dynamics and natural selection. Environmental heterogeneity can influence the outcome of interactions by affecting the intensity of interactions, but also by affecting the demography of the populations involved. However, little is known about the relative importance of environmental effects on interaction intensities and demographic sensitivity for variation in population growth rates. We investigated how soil depth, soil moisture, soil nutrient composition, and vegetation height influenced the intensity of seed prédation as well as host plant demography and sensitivity to seed prédation in the perennial herb Primula farinosa. Intensity of seed prédation ranged from 0% to 80% of seeds damaged among the 24 study populations and was related to soil moisture in two of four years. The effect of seed prédation on plant population growth rate (λ) ranged from negligible to a reduction in X by 0.70. Sensitivity of population growth rate to prédation explained as much of the variation in the reductions in population growth rate due to seed prédation as did prédation intensity. Plant population growth rate in the absence of seed prédation and sensitivity to prédation were negatively related to soil depth and soil moisture. Both intensity of prédation and sensitivity to prédation were positively correlated with potential population growth rate and, as a result, there was no significant relationship between prédation intensity and realized population growth rate. We conclude that in our study system environmental context influences the effects of seed prédation on plant fitness and population dynamics in two important ways: through variation in interaction intensity and through sensitivity to the effects of this interaction. Moreover, our results show that a given abiotic factor can influence population growth rate in different directions through effects on potential growth rate, intensity of biotic interactions, and the sensitivity of population growth rate to interactions. [ABSTRACT FROM AUTHOR]

A novel framework is presented for the analysis of ecophysiological field measurements and modelling. The hypothesis ' leaves minimise the summed unit costs of transpiration and carboxylation' predicts leaf-internal/ambient CO2 ratios ( c i /c a) and slopes of maximum carboxylation rate ( Vcmax) or leaf nitrogen ( Narea) vs. stomatal conductance. Analysis of data on woody species from contrasting climates (cold-hot, dry-wet) yielded steeper slopes and lower mean c i /c a ratios at the dry or cold sites than at the wet or hot sites. High atmospheric vapour pressure deficit implies low c i /c a in dry climates. High water viscosity (more costly transport) and low photorespiration (less costly photosynthesis) imply low c i /c a in cold climates. Observed site-mean c i /c a shifts are predicted quantitatively for temperature contrasts (by photorespiration plus viscosity effects) and approximately for aridity contrasts. The theory explains the dependency of c i /c a ratios on temperature and vapour pressure deficit, and observed relationships of leaf δ13C and Narea to aridity. [ABSTRACT FROM AUTHOR]

* Premise of the Study: Conserving endangered plants is a complex task, and practitioners must often use a "triage" approach, addressing only immediate needs. Ecologists can improve this process by conducting sound science upon which to base management. Marsilea villosa is an endangered, endemic Hawaiian fern with seven remaining populations in ephemerally flooding drylands. Among its uncommon traits are long-lived sporocarps, requiring flood and drought to complete its sexual life cycle, and extensive vegetative growth. * Methods: We conducted a 3-yr ecological field study, measuring percent cover of M. villosa and associated species, flooding depth, and canopy cover, to identify ecological factors with the greatest impact on M. villosa growth. * Key Results: Maximum flooding depth and canopy cover had strong positive relationships with M. villosa growth, and all plots with >50% threshold of either variable reached 100% cover of M. villosa by the end of the study. Interaction effects explained nuances of these relationships, including synergy between the two variables. Percent cover of nonnative functional groups (graminoids and nongraminoids) each had negative relationships with M. villosa growth, but interactions showed that nongraminoid cover was driven by particular species, and that time since flooding had greater influence on M. villosa growth than graminoid cover. * Conclusions: We recommend planting reintroduced populations in flood-prone areas with moderate shade, experimental outplanting of native plants with M. villosa, and management of graminoids as a functional group, while nongraminoid management should be species-specific. These practices will promote self-sustaining populations and reduce the need for labor-intensive management. [ABSTRACT FROM AUTHOR]

Contents [ABSTRACT FROM AUTHOR]

Dry forests are among the most endangered natural communities in the Hawaiian Islands. Most have been reduced to isolated trees and small forest fragments in which native tree species reproduce poorly. The replacement of native birds by introduced generalists may be contributing to dry forest decline through modification of seed dispersal patterns. To document seed dispersal by introduced birds, we conducted foraging observations on fleshy-fruited trees and measured seed rain under trees and in adjacent open areas for 1 year in a dry forest dominated by native trees. Although trees covered only 15.2 percent of the study area, 96.9 percent of the bird-dispersed seeds were deposited beneath them. The Japanese white-eye ( Zosterops japonicus) was the principal dispersal agent. Among bird-dispersed seeds, those of the invasive tree Bocconia frutescens accounted for 75 percent of all seeds collected beneath trees (14.8 seeds/m2/yr) and the invasive shrub Lantana camara accounted for 17 percent. Although nearly 60 percent of the reserve's native woody species possess fleshy fruits, introduced birds rarely disperse their seeds. Native trees accounted for <8 percent of all bird-dispersed seeds and are consequently experiencing dispersal failure by falling directly under parent trees. Smaller-seeded non-native plants, in contrast, may be benefiting from dispersal by introduced birds. Current dispersal patterns suggest that these readily disseminated non-native plants may eventually replace the remaining native flora. [ABSTRACT FROM AUTHOR]

Aim The distributions of many New Caledonian taxa were reviewed in order to ascertain the main biogeographical connections with other areas. Location Global. Methods Panbiogeographical analysis. Results Twenty-four areas of endemism (tracks) involving New Caledonia and different areas of Gondwana, Tethys and the central Pacific were retrieved. Most are supported by taxa of lower and higher plants, and lower and higher animals. Main conclusions Although parts of New Caledonia were attached to Gondwana for some time in the mid-Cretaceous, most of the New Caledonian terranes formed as oceanic island arcs and sections of sea floor bearing seamounts. The flora and fauna have evolved and survived for tens of millions of years as metapopulations on ephemeral islands. Later, the biotas were juxtaposed and fused during terrane accretion. This process, together with the rifting of Gondwana, explains the biogeographical affinities of New Caledonia with parts of Gondwana, Tethys and the Pacific. [ABSTRACT FROM AUTHOR]

Aim We used a combination of new and previously published palaeoecological data to test three hypotheses: (1) that wooded steppe persisted in the Great Hungarian Plain throughout the Holocene; (2) that wooded steppe and steppe were most extensive between c. 9900 and 8300 cal. yr bp (the ‘Boreal steppe’ period); and (3) that Southern Continental, Pontic and Eastern Sub-Mediterranean steppe species reached the region during the early Holocene via the ‘Lower Danube Corridor’. Location Sarló-hát oxbow lake, Hungary and the Eastern European wooded steppe zone. Methods Holocene sediments deposited in the Sarló-hát oxbow lake were subjected to pollen and microcharcoal analyses. Twelve radiocarbon age estimates were obtained to determine sediment chronology. In addition, previously published palaeoecological data from the Great Hungarian Plain were compiled, analysed and compared with previous studies in other regions of steppe and wooded steppe in eastern Europe. Results Palynological data from two sediment cores extending to c. 11,400 cal. yr bp indicate the persistent dominance of the landscape by temperate deciduous wooded steppe throughout the Holocene, although with varying canopy composition. Warm-continental steppe grasslands and saline tall-grass meadows developed on edaphically constrained areas, which remained steppe-dominated throughout the Holocene. The extent of steppe grasslands did not increase between 9900 and 8300 cal. yr bp. After c. 3100 cal. yr bp, anthropogenic activities led to the development of cultural steppe. Thermophilous steppe species of the Southern Continental, Pontic and Sub-Mediterranean floristic elements probably reached the Great Hungarian Plain principally via the Lower Danube Corridor during the late glacial interstadial and Holocene. Eurythermic members of these elements, however, probably survived the Last Glacial Maximum in favourable microsites, extending their ranges during the Holocene from these local sources. Main conclusions Our results confirm the Holocene persistence of wooded steppe in the Great Hungarian Plain, disprove the ‘Boreal steppe’ theory, and suggest an Early Holocene period of greater vegetation openness between 11,400 and 9900 cal. yrbp. Evidence for the post-glacial immigration of south-eastern steppe elements into the Carpathian Basin is equivocal: the last glacial/interglacial presence of several southern steppe species suggests that the Hungarian Plain hosted suitable habitats for them during warm and cold phases alike. [ABSTRACT FROM AUTHOR]

The tropical dade of Orobanchaceae contains approximately forty genera, typically with fewer than ten species each, and contributes significantly to the variation in floral morphology found within the family. Despite the economic importance of this dade, which contains three of four most important genera of crop parasites within the family, it has been under-sampled in previous phylogenies. We tested the monophyly of the tropical dade and its major genera using DNA sequences from the nuclear (internal transcribed spacer) and plastid (rpll6, trnT-L) genomes. The tropical dade was strongly supported as mono-phyletic in all analyses, and four main clades were recovered. The earliest diverging lineage from the remainder of the tropical dade is comprised of the shrubby genera Asepalum and Cyclocheilon, previously placed within Cyclocheilaceae. The atypical holoparasitic Alectra alba was shown to belong within the primarily holoparasitic Harveya, and the hemiparasitic Harveya obtusifolia was shown to belong to an otherwise holoparasitic lineage within Harveya. Both New World Melasma species were included here for the first time, and these were shown to be more closely related to the Neotropical hem iparasitic Escobedia than the African Melasma lineage. These results support a previous study recognizing Nesogenes within the tropical dade of Orobanchaceae rather than the separate family Nesogenaceae. [ABSTRACT FROM AUTHOR]

•Stem mechanical properties are critically linked to foliage deployment and growth strategy, yet variation in stem mechanics across species and habitats is poorly understood. •Here, we compared 32 plant species growing across four sites of contrasting rainfall and soil nutrient availability in Australia. •The modulus of elasticity (MOE) and modulus of rupture (MOR) were tightly correlated with dry sapwood density within sites, but species from low-rainfall environments had higher wood density for a given MOE and MOR compared with species growing in high-rainfall environments. The ratio of MOE to MOR was slightly lower for species at low-rainfall sites, suggesting that wood was stronger for a given elasticity. Most species had thick bark, but the mechanical contribution of bark to stem MOE was small. •Our results suggest that arid-adapted species would need to deploy more dry mass to support stems. Our results also highlight the importance of understanding how the biomechanics–wood density relationship evolves under different environmental conditions to better understand plant growth across diverse habitats. [ABSTRACT FROM AUTHOR]

1. Leaf trait relationships of native and exotic invasive species from a range of habitats were compared to assess consistency across habitats and the role of disturbance. 2. One hundred and twenty-two native and exotic species were sampled in five habitats in eastern Australia. Specific leaf area, foliar nitrogen ( Nmass), assimilation rate ( Amass) and dark respiration ( Rmass) were measured for each species. Plants were classified into four types: native undisturbed, native disturbed, exotic invasive undisturbed and exotic invasive disturbed. 3. All traits were positively correlated and slopes were homogeneous within habitats. Significant differences between plant types in slope elevation were found in only two of 18 cases. There were significant shifts in group means along a common slope between plant types within habitats. These shifts were associated with disturbed vs. undisturbed areas, with plant types from disturbed areas having higher trait values. 4. Synthesis. Exotic invasive and native species do not have fundamentally different carbon capture strategies. The carbon capture strategy of a species is strongly associated with disturbance, with species from disturbed sites having traits that confer capacity for fast growth. Thus, differences between exotic invasives and natives may reflect differences in the environmental conditions of the sites where they occur rather than differences between exotic invasives and natives per se. [ABSTRACT FROM AUTHOR]

The size of fleshy fruits spans several orders of magnitude. However, the evolution of fruit size diversity is poorly understood. Fruit size diversity is hypothesised to result from several potential processes. The frugivore hypothesis postulates that different-sized animal fruit consumers select for different-sized fruits. The correlated selection hypothesis postulates that fruit size is allometrically related to other plant traits (e.g. leaf size, plant height); therefore differences in fruit size result from correlated evolution with other plant traits. We tested the frugivore and correlated selection hypotheses as potential explanations for fruit size diversity in two New Zealand study sites. We observed birds foraging for fruits over two fruiting seasons at each site and measured fruit size, leaf size and plant height in a total of 32 plant species. Relationships between average fruit size, leaf size, plant size and the average size of birds consuming each fruit species were then evaluated using phylogenetically independent contrasts. Similar results were obtained in both study sites. Fruit size was correlated with the size of avian fruit consumers, but was unrelated to leaf size or plant height. Therefore, results falsified the correlated selection hypothesis but failed to falsify the frugivore hypothesis. Although results suggest that frugivores may have influenced the evolution of fruit size in New Zealand, further study is needed to generate a mechanistic understanding of how frugivores may have selected for interspecific variation in fruit size. [ABSTRACT FROM AUTHOR]

1. This account presents information on all aspects of the biology of Primula vulgaris Huds. (Primrose) that are relevant to understanding its ecological characteristics and behaviour. The main topics are presented within the framework of the Biological Flora of the British Isles: distribution, habitat, communities, responses to biotic factors, responses to environment, structure and physiology, phenology, floral and seed characteristics, herbivores and disease, history and conservation. 2. Primula vulgaris is a native perennial herb with a very wide distribution in the British Isles. In many lowland areas it is essentially a plant of woodlands and hedgerows, although in the west it can occur abundantly in grasslands and other communities such as heaths. In northern and western Britain and Ireland, it may be frequent in open and even exposed habitats. Its distribution is linked with soil moisture and atmospheric humidity. It is shade tolerant, but it flowers most profusely in canopy gaps. 3. Primula vulgaris is a rosette hemicryptophyte that reproduces mainly through seeds. Vegetative spread is restricted and only occurs within very short distances from the mother plant through the production of lateral rosettes. Although individual rosettes may die, plants are relatively long-lived (life expectancy of a newborn individual: 48.3 years). The mean age at first flowering was 20 months. 4. Pollination is mainly by bumblebees and other bees, but other long-tongued pollinators including syrphids, bee-flies and even butterflies may be locally important. P. vulgaris is an obligate outbreeder, with two genetically determined self-incompatible morphs (‘pin’ and ‘thrum’). A third morph (‘homostyle’ or ‘long homostyle’), with a stigma like that of pin but anthers like that of thrum, has been found in Somerset and North Dorset. In years when pollinators are scarce, homostyles have higher reproductive success than pins and thrums, suggesting that reproductive assurance could have had a profound effect on the evolution of homostyly in P. vulgaris. 5. Seeds are dispersed by ants and rodents. Dispersal is usually restricted to a few centimetres or decimetres from maternal plants, resulting in significant fine-scale spatial genetic structure and small neighbourhood sizes. Pollen flow, on the other hand, is more extensive, but still limited to a few metres from paternal plants. 6. Populations of P. vulgaris have not changed markedly during the last century in most parts of Britain and Ireland and it is not threatened with extinction nationally. However, there is evidence that Primroses were formerly more widespread and have decreased with the decline of coppicing and pollarding. In East Anglia, woodland populations have declined greatly in response to a series of hot, dry summers since 1970. Small, isolated populations of P. vulgaris often show reduced reproductive success, potentially affecting their long-term survival. Preservation of local habitat conditions and restoration of gene flow among populations are required to maintain viable populations of P. vulgaris in the long term. [ABSTRACT FROM AUTHOR]

1. This account presents information on all aspects of the biology of Primula elatior that are relevant to understanding its ecological characteristics and behaviour. The main topics are presented within the standard framework of the Biological Flora of the British Isles: distribution, habitat, communities, responses to biotic factors, responses to environment, structure and physiology, phenology, floral and seed characters, herbivores and disease, history, and conservation. 2. Primula elatior is a native perennial herb, within a compact area in the British Isles, in ancient woods and copses on the chalky boulder clay in East Anglia, where it is abundant locally although scarce nationally. British material is ssp. elatior, which extends across much of Europe, becoming rarer towards the south. 3. Primula elatior is a shade tolerant species, but only flowers in profusion in the increased light levels following tree felling in traditionally coppiced woods. It is confined to an area of the British Isles where the soils are seasonally waterlogged and ill-aerated, and is very tolerant of the toxic levels of ferrous iron which accumulate in the surface horizons in the spring months. It has a poorly developed drought tolerance. 4. An early flowering plant, P. elatior is an insect-pollinated obligate outbreeder, with two self-incompatible morphs (pin and thrum). The low colonizing ability of this ancient woodland species can be attributed to both seed dispersal and seedling recruitment limitation. 5. There has been a steady reduction in the density of P. elatior in woodland sites during the past centuries. However, there has been little change in the 10-km distribution in the British Isles. Studies of populations involve three groups of factors: genetic variation, environmental changes and population structure. Potentially these factors have a greater effect on small and isolated populations than on large and integrated ones. There is no evidence that the species suffers from a loss of genetic diversity in the smaller populations. Primula elatior seems to have a relatively high level of genetic diversity that is maintained despite a fragmented distribution. 6. Within its restricted distribution area P. elatior replaces P. vulgaris completely. At the margins of their distributions the two species occur together in a number of woodland sites, providing the opportunity for hybridization. As they are highly interfertile, hybridization is restricted mainly by differences in their habitat preferences. The hybrid P. vulgaris ×  P. elatior =  P. ×  digenea is fertile and gives rise to hybrid swarms which are found in all British sites where both parents occur together. 7. Changes in climate, woodland management practices and intensities of deer grazing, especially by Fallow deer ( Dama dama), are likely to have a major effect on populations of P. elatior. Since the species colonizes new or secondary woodlands very slowly, management should focus on the conservation of ancient semi-natural woodlands. [ABSTRACT FROM AUTHOR]

Leaf miners are insects whose larval stages live between layers of leaf epidermis, feeding on mesophyll and lower epidermis to create mine-like cavities. Little is known about the ecology or distribution of leaf miners in Australia. We investigated the incidence of leaf miners in relation to aridity, vegetation types, host plant taxonomy, leaf traits, canopy cover and latitude. We surveyed leaf miners at 15 sites in NSW, eastern Australia, situated along a rainfall gradient from 300 to 1700 mm per annum and a latitudinal gradient of 28°S to 33°S, within four vegetation types (mallee, heath, woodland and rainforest). Leaf mining was recorded from 36 plant species, 89% of which had no previous record of mining. The proportion of mined plant species at each site varied, but there was no significant difference between vegetation types. Leaf mining presence was positively correlated with both total leaf length and leaf thickness. No significant correlations were found between the proportion of mined species at a site and rainfall, latitude or foliar projected cover. We conclude that leaf mining is a widespread type of insect herbivory whose distribution patterns are more likely to be influenced by biotic than abiotic factors. [ABSTRACT FROM AUTHOR]

Aim We review several aspects of the structure of regional and local assemblages of nectar-feeding birds and bats and their relationships with food plants to determine the extent to which evolutionary convergence has or has not occurred in the New and Old World tropics. Location Our review is pantropical in extent and also includes the subtropics of South Africa and eastern Australia. Within the tropics, it deals mostly with lowland forest habitats. Methods An extensive literature review was conducted to compile data bases on the regional and local species richness of nectar-feeding birds and bats, pollinator sizes, morphology, and diets. Coefficients of variation (CVs) were used to quantify the morphospace occupied by the various families of pollinators. The extent to which plants have become evolutionarily specialized for vertebrate pollination was explored using several criteria: number and diversity of growth forms of plant families providing food for all the considered pollinator families; the most common flower morphologies visited by all the considered pollinator families; and the number of plant families that contain genera with both bird- and bat-specialized species. Results Vertebrate pollinator assemblages in the New World tropics differ from those in the Old World in terms of their greater species richness, the greater morphological diversity of their most specialized taxa, and the greater degree of taxonomic and ecological diversity and morphological specialization of their food plants. Within the Old World tropics, Africa contains more specialized nectar-feeding birds than Asia and Australasia; Old World nectar-feeding bats are everywhere less specialized than their New World counterparts. Main conclusions We propose that two factors – phylogenetic history and spatio-temporal predictability (STP) of flower resources – largely account for hemispheric and regional differences in the structure of vertebrate pollinator assemblages. Greater resource diversity and resource STP in the New World have favoured the radiation of small, hovering nectar-feeding birds and bats into a variety of relatively specialized feeding niches. In contrast, reduced resource diversity and STP in aseasonal parts of Asia as well as in Australasia have favoured the evolution of larger, non-hovering birds and bats with relatively generalized feeding niches. Tropical Africa more closely resembles the Neotropics than Southeast Asia and Australasia in terms of resource STP and in the niche structure of its nectar-feeding birds but not its flower-visiting bats. [ABSTRACT FROM AUTHOR]

The African Plant Checklist and Database Project (APCD) provides botanists with the first angiosperm checklist and database for Sub-Saharan Africa. This was achieved by merging the existing datasets for Southern and Tropical Africa. The checklist is published as a one-off hardcopy publication. The database, with all attached additional information, is freely accessible via the internet and will be regularly updated. The APCD, for the first time, gives accurate statistics for the angiosperm flora of Sub-Saharan Africa. There are 50,136 current taxa (representing approximately 44,830 species) in the database, plus an additional 393 taxa where there are discrepancies in genus concept between the two original datasets. Taxa are classified into 274 families and 3,802 current genera. Several other important statistics can also be drawn from the database. Furthermore, by pointing out problems and discrepancies in taxonomic opinion, the APCD highlights taxa where further research is necessary. The APCD will be an invaluable tool to botanists working on the African flora. It also has an important role to play in greater projects such as the Global Plant Checklist Project and has already emerged as a nomenclatural standard for the African Plants Initiative. [ABSTRACT FROM AUTHOR]

Aim Conflicting perceptions of past and present rangeland condition and limited historical data have led to debate regarding the management of vegetation in pastoral landscapes both internationally and in Australia. In light of this controversy we have sought to provide empirical evidence to determine the trajectory of vegetational change in a semi-arid rangeland for a significant portion of the 20th century using a suite of proxy measures. Location Ambathala Station, approximately 780 km west of Brisbane, in the semi-arid rangelands of south-western Queensland, Australia. Methods We excavated stratified deposits of sheep manure which had accumulated beneath a shearing shed between the years 1930 and 1995. Multi-proxy data, including pollen and leaf cuticle analyses and analysis of historical aerial photography were coupled with a fine resolution radiocarbon chronology to generate a near annual history of vegetation on the property and local area. Results Aerial photography indicates that minor (< 5%) increases in the density of woody vegetation took place between 1951 and 1994 in two thirds of the study area not subjected to clearing. Areas that were selectively or entirely cleared prior to the 1950s (approximately 16% of the study area) had recovered to almost 60% of their original cover by the 1994 photo period. This slight thickening is only partially evident from pollen and leaf cuticle analyses of sheep faeces. Very little change in vegetation is revealed over the nearly 65 years based on the relative abundances of pollen taxonomic groups. Microhistological examination of sheep faeces provides evidence of dramatic changes in sheep diet. The majority of dietary changes are associated with climatic events of sustained above-average rainfall or persistent drought. Most notable in the dietary analysis is the absence of grass during the first two decades of the record. Main conclusions In contrast to prevailing perceptions and limited research into long-term vegetation change in the semi-arid areas of eastern Australia, the record of vegetation change at the Ambathala shearing shed indicates only a minor increase in woody vegetation cover and no decrease in grass cover on the property over the 65 years of pastoral activity covered by the study. However, there are marked changes in the abundance of grass cuticles in sheep faeces. The appearance and persistence of grass in sheep diets from the late 1940s can be attributed to the effects of periods of high rainfall and possibly some clearing and thinning of vegetation. Lower stock numbers may have allowed grass to persist through later drought years. The relative abundances of major groups of plant pollen have not changed significantly over the past 65 years. [ABSTRACT FROM AUTHOR]

The Flora Reipublicae Popularis Sinicae (FRPS) is one of the largest floristic projects in the world. The final product, 80 volumes in 126 parts, represents work by four generations of Chinese plant taxonomists during 45 years (1959-2004) and treats 31,180 species (300 families, 3,434 genera) on over 40,000 pages. More than half of the species (54%) are endemic to China. This monumental flora has not yet been thoroughly reviewed. The history of the project is described with comments on outline, statistics, largest families and genera, names of authors and editors, quality, species concept, new taxa, specimens, and proofing and indexing. [ABSTRACT FROM AUTHOR]

Aim To determine whether life-history characters that affect population persistence (e.g. habit and life span) and those that influence reproductive success (e.g. sexual system and fruit type) are non-randomly correlated with extinction risk (i.e. threat category) in the Australian flora ( c. 19,000 species, of which c. 14% is threatened). To identify patterns that present useful conservation directions. To understand patterns of extinction risk in the Australian flora at a broad scale. Location Continental Australia. Methods A country-wide exploration of four life-history characters in the Australian flora ( n = 18,822 species) was undertaken using reference texts, expert opinion, herbarium records and field work. For each character and threat-category combination, a G-test (using a log-linear model) was performed to test the null hypothesis that the two factors were independent in their effects on count. A generalized linear model (GLM) with a logit link and binomial error distribution was constructed with the proportion of taxa in each extinction risk category as the response variable and the habit, sex and fruit-type characters as explanatory terms. In a separate approach, we investigated patterns across the threat categories of non-endangered extant, endangered, and extinct using a multinomial model. We examined whether or not species-poor genera were more likely to contain threatened or extinct species than species-rich genera. A GLM with a binomial error distribution and logit link function was constructed to obtain a weighted regression on the proportion of species listed as extinct or endangered within a genus versus the log of the size of the genus. We also used a supertree analysis and character tracing to investigate the role of phylogeny on extinction risk. Results We found that the Australian flora is primarily composed of bisexual shrubs with dry-dehiscent fruits. Dioecious breeding systems (separate female and male flowers on separate plants) in many floras are the predominant unisexual system, but in Australia there are unexpectedly high levels of monoecy (separate female and male flowers on the same plant). Within the extinct data set of 31 species we detected a significant departure from that expected for habit but not for life span, sexual system or fruit type. There are significantly fewer trees on the extinct list than expected. This may reflect the greater resilience of trees than of other growth habits to extinction processes as well as the observation time-frame. Within the endangered data set of 450 species we found significant differences in the representation of the observed characters from that expected within sex systems and fruit types. We show that, depending on the life form, unisexual breeding systems can be significantly and positively associated with endangered species compared with non-threatened species. For example, there are more monoecious species than expected by chance among the tree species listed as endangered but fewer among the herbaceous life forms. Threat category was found to be non-randomly clustered in some clades. Main conclusions Life-history characters in certain combinations are predictive of extinction risk. Phylogeny is also an important component of extinction risk. We suggest that specific life-history characters could be used for conservation planning and as an early warning sign for detecting vulnerability in lists of species. [ABSTRACT FROM AUTHOR]

A phylogenetic study of plastid DNA sequences (ndhF, trnL/F, and rps16) in Lamiales is presented. In particular, the inclusiveness of Scrophulariaceae sensu APG II is elaborated. Scrophulariaceae in this sense are mainly a southern hemisphere group, which includes Hemimerideae (including Alonsoa, with a few South American species), Myoporeae, the Central American Leucophylleae (including Capraria), Androya, Aptosimeae, Buddlejeae, Teedieae (including Oftia, Dermatobotrys, and Freylinia), Manuleeae, and chiefly Northern temperate Scrophularieae (including Verbascum and Oreosolen). Camptoloma and Phygelius group with Buddlejeae and Teedieae, but without being well resolved to any of these two groups. Antherothamnus is strongly supported as sister taxon to Scrophularieae. African Stilbaceae are shown to include Bowkerieae and Charadrophila. There is moderate support for a clade of putative Asian origin and including Phrymaceae, Paulownia, Rehmannia, Mazus, Lancea, and chiefly parasitic Orobanchaceae, to which Brandisia is shown to belong. A novel, strongly supported, clade of taxa earlier assigned to Scrophulariaceae was found. The clade includes Sternodiopsis, Torenia, Micranthemum and probably Picria and has unclear relationships to the rest of Lamiales. This clade possibly represents the tribe Lindernieae, diagnosed by geniculate anterior filaments, usually with a basal swelling. [ABSTRACT FROM AUTHOR]

A widely-used description of vegetation response to fire is that species can be clearly classified as sprouters or non-sprouters. We aimed to assess: (1) how well this dichotomous classification (sprouter/non-sprouter) described the responses of a semi-arid flora to experimental disturbance; (2) how similar were sprouting responses to treatments mimicking intense herbivory and fire; (3) how well easily-measured traits could predict sprouting. Sprouting was assessed for 45 species from a range of growth forms (grasses, forbs, sub-shrubs, woody shrubs and trees) from semi-arid south-eastern Australia. We used two treatments: clipping at stem base, and clipping followed by burning with a blowtorch.A dichotomy accounted for>60% of deviance explained by species identity. Models with three or four groups were not substantially better. The dichotomy was not between 0% and 100% sprouting, rather between‘weak’ and‘strong’ sprouters. Probabilities of sprouting for weak sprouters were 23% after clipping and 6% after burning, while strong sprouters had sprouting probabilities of 90% after clipping and 79% after burning. While sprouting varied in space and time, the dichotomy was robust to this variation. Sprouting ability increased with size in most of the species with variable sprouting.Sprouting was partially related to growth form; grasses sprouted strongly, chenopods weakly, and forb and woody species covered the range of sprouting. Strong sprouters were likely to have more stems per plant, greater basal area, shorter potential height and deeper buds than weak sprouters. A hierarchical model that used growth form and then stems-per-plant provided a simple, robust predictor of sprouting.Four-fifths of species responded consistently to clipping and burning while one-fifth of species were strong sprouters after clipping but weak sprouters after burning. Burning reduced sprouting most in intermediate sprouters. Differences between sprouting after clipping and burning reflected increased intensity and were related to the depth of buds below ground. [ABSTRACT FROM AUTHOR]

This paper documents reconstructions of the vegetation patterns in Australia, Southeast Asia and the Pacific (SEAPAC region) in the mid-Holocene and at the last glacial maximum (LGM). Vegetation patterns were reconstructed from pollen data using an objective biomization scheme based on plant functional types. The biomization scheme was first tested using 535 modern pollen samples from 377 sites, and then applied unchanged to fossil pollen samples dating to 6000 ± 500 or 18,000 ± 1000 14C yr bp. 1. Tests using surface pollen sample sites showed that the biomization scheme is capable of reproducing the modern broad-scale patterns of vegetation distribution. The north–south gradient in temperature, reflected in transitions from cool evergreen needleleaf forest in the extreme south through temperate rain forest or wet sclerophyll forest (WSFW) and into tropical forests, is well reconstructed. The transitions from xerophytic through sclerophyll woodlands and open forests to closed-canopy forests, which reflect the gradient in plant available moisture from the continental interior towards the coast, are reconstructed with less geographical precision but nevertheless the broad-scale pattern emerges. 2. Differences between the modern and mid-Holocene vegetation patterns in mainland Australia are comparatively small and reflect changes in moisture availability rather than temperature. In south-eastern Australia some sites show a shift towards more moisture-stressed vegetation in the mid-Holocene with xerophytic woods/scrub and temperate sclerophyll woodland and shrubland at sites characterized today by WSFW or warm-temperate rain forest (WTRF). However, sites in the Snowy Mountains, on the Southern Tablelands and east of the Great Dividing Range have more moisture-demanding vegetation in the mid-Holocene than today. South-western Australia was slightly drier than today. The single site in north-western Australia also shows conditions drier than today in the mid-Holocene. Changes in the tropics are also comparatively small, but the presence of WTRF and tropical deciduous broadleaf forest and woodland in the mid-Holocene, in sites occupied today by cool-temperate rain forest, indicate warmer conditions. 3. Expansion of xerophytic vegetation in the south and tropical deciduous broadleaf forest and woodland in the north indicate drier conditions across mainland Australia at the LGM. None of these changes are informative about the degree of cooling. However the evidence from the tropics, showing lowering of the treeline and forest belts, indicates that conditions were between 1 and 9 °C (depending on elevation) colder. The encroachment of tropical deciduous broadleaf forest and woodland into lowland evergreen broadleaf forest implies greater aridity. This study provides the first continental-scale reconstruction of mid-Holocene and LGM vegetation patterns from Australia, Southeast Asia and the Pacific (SEAPAC region) using an objective biomization scheme. These data will provide a benchmark for evaluation of palaeoclimate simulations within the framework of the Palaeoclimate Modelling Intercomparison Project. [ABSTRACT FROM AUTHOR]

We analysed the interdependence of avian frugivore- and fruited plant-species richness at the scale of major river basins across Europe, taking into account several environmental factors along different spatial gradients. Continental Europe and the British Isles. We focused on wintering birds and autumn/winter fruiting plants, and used major river basins as geographical units and Structural Equation Modelling as the principal analytical tool. The statistical influence of disperser species richness on fleshy-fruited plant species richness is roughly double that of the reverse. Broad-scale variation in frugivore richness is more dependent on environmental factors than on fruited plant richness. However, the influence of disperser richness on plant richness is four times higher than the influence of environmental factors. Environmental influences on both birds and plants are greater than purely spatial influences. Our results are interpreted as indicating that biotic dispersal of fruits strongly affects broad-scale geographical trends of fleshy-fruited plant species richness, whereas richness of fruited plants moderately affects frugivore richness. [ABSTRACT FROM AUTHOR]

Androdioecy, the co-occurrence of males and hermaphrodites in a breeding population, is a rare reproductive system in the nature. This rarity may be the result of the large fitness gain required for male plants to be maintained by selection. Physiological, vegetative and reproductive characters of males and hermaphrodites of the androdioecious species Fraxinus ornus (Oleaceae) were compared, supporting the hypothesis that males compensate the fitness advantage of hermaphrodites with greater reproductive -but not vegetative- output, with concomitant differences in physiological capacities between the genders. Photosynthetic rate was similar between both genders, but hermaphrodites had lower water potential and carbon isotope discrimination than males. Photosynthesis rates decreased with decreasing water potentials more steeply in males than in hermaphrodites, indicating that hermaphrodites were more drought tolerant than males. Vegetative characters such as current year shoot growth or tree size did not differ between genders. Males produced 1.6 times more inflorescences than hermaphrodites. This difference was consistent across years and populations. [ABSTRACT FROM AUTHOR]

Leaf morphology varies predictably with altitude, and leaf morphological features have been used to estimate average temperatures from fossil leaves. The altitude-leaf morphology relationship is confounded by the two processes of acclimation and adaptation, which reflect environmental and genetic influences, respectively. Here we describe the relationship between altitude and leaf morphology for Southern beech, Nothofagus cunninghamii (Hook.) Oerst.. Cuttings from several trees from each of four altitudes were grown in a common glasshouse experiment, and leaf morphology related to both genotype and altitude of origin. Genotype had a significant impact on leaf morphology, but in the field there was also a significant, overriding effect of altitude. This altitude effect disappeared in glasshouse-grown plants for all morphological variables other than leaf thickness and specific leaf area. These results show that, while leaf length, width and area are partially controlled by genetic factors, these variables are plastic and respond to environmental influences associated with a particular altitude. Thus altitudinal trends in leaf size in N. cunninghamii are unlikely to be the result of adaptation. [ABSTRACT FROM AUTHOR]

Summary Many Australian plant species and communities appear to be threatened by tourism. A review of management plans, recovery plans and a survey of experts found that tourism was considered to be a direct or indirect threatening process for 72 plant taxa. This is one fifth of threatened species for which threats have been identified. In addition, many more species are listed as threatened by weeds, trampling, pathogens, clearing and collecting. These are often indirect impacts of tourism, particularly in conservation reserves where tourism is the only commercial activity permitted. Tourism was also considered to be a threatening process for several plant communities. A lack of recognition of the importance of direct and indirect impacts of tourism may potentially hinder the conservation of plant species and communities both in Australia and overseas. It may also limit the effectiveness of sustainable tourism policies, particularly in conservation reserves. [ABSTRACT FROM AUTHOR]

Summary 1. Most plants withdraw nutrients from leaves as they age, and redeploy them elsewhere in the plant. The proportion of nutrients resorbed and the residual nutrient concentration in senesced leaves are different but complementary indices of nutrient conservation via this process. A major spectrum of strategic variation runs from plant species with typically long leaf lifespan (LL), high leaf mass per area (LMA), low leaf nutrient concentrations, and low photosynthetic capacity, to species with the opposite characteristics. It is unknown to what extent either facet of resorption covaries with the LL–LMA spectrum. 2. Green-leaf and senesced-leaf N and P concentrations were quantified for 73 evergreen species from four sites in eastern Australia (nutrient-rich and nutrient-poor sites in each of two rainfall zones). Leaf nutrient concentrations in green and senesced leaves were negatively correlated with LL across all species and at most sites, especially if N2 -fixing species were excluded from analyses involving leaf N. 3. Proportional resorption did not differ with soil nutrients, as has been found elsewhere, nor was it correlated with LL. Green-leaf and senesced-leaf nutrient concentrations were lower for species on poorer soils. A simple model was described in which the proportion of resorbed vs soil-derived nutrients deployed in new leaves is set by the relative cost of nutrients from the two sources. The model provides a prospective explanation for the observed differences between species from nutrient-rich and nutrient-poor habitats. 4. The results from this study provide support for the argument that selection to minimize nutrient losses has affected the residual nutrient concentration in senesced leaves, rather than proportional resorption per se . Further, variation among species in residual nutrient concentration was correlated with one of the key spectra of strategic variation between plant species, the leaf lifespan–LMA... [ABSTRACT FROM AUTHOR]

Summary 1. To explore how rangeland grazing affects native plant diversity at local and regional scales, we measured the frequency of occurrence of plant species along six transects spread across a large region of arid calcareous rangelands in north-western South Australia. Four transects were in commercial sheep-grazed paddocks and two were in otherwise similar lands that had never been developed for pastoralism. Each transect comprised four sites of area 0·5 km2 , at distances of 1, 4, 7 and 10 km from the nearest stock watering point in a paddock, or from a nominal starting point > 10 km from water in the undeveloped lands. 2. Nearly 200 plant species were recorded, but distributions were patchy, with > 30% of species present at < 10% of sites. 3. The apparent influence of pastoral development and proximity to water varied with the scale of inquiry. At the regional level, pastoral development had a predominantly negative effect on the abundance of species: 16 species were less abundant in paddocks than in lands that had never been developed, and only one species was more abundant. Localized trends within paddocks were more positive: significantly more species showed trends of increasing abundance with increasing proximity to watering points and associated grazing activity. 4. The study results are consistent with a general pattern whereby pastoral development enhances richness of plant species at a local scale (by providing opportunities for more species to establish) but has the potential to decrease it at a regional scale (by removing the most grazing-sensitive species from the regional species pool). 5. The results suggest there may be two fundamentally different mechanisms whereby species decline in abundance under grazing. Palatable, drought-hardy, perennial species are more likely to decline in abundance with proximity to water and associated accumulated grazing pressure in paddocks. Uncommon or short-lived species that are selectively... [ABSTRACT FROM AUTHOR]

Aim To evaluate competing views on the origin and distribution of the New Zealand flora by testing the hypothesis that the geographical distribution of species is unrelated to ecological traits such as habitat requirements and dispersal capabilities. Location The New Zealand archipelago. Methods An analysis of the factors correlated with distribution and endemism for alpine plants within New Zealand, and for the New Zealand biota as a whole. Results Woody plants are highly endemic; nonendemic plants tend to be herbaceous and are concentrated among the highly dispersible ferns and fern allies, orchids and wetland plants. These groups make up 32% of the total flora but contribute 78% of nonendemics. Alpine plants with wide spatial distribution tend to have greater altitudinal ranges, a broader habitat preference and better dispersal ability. Main conclusions Most vascular plants reached New Zealand by long-distance transoceanic dispersal, probably during the Late Miocene to early Pleistocene period. During the Miocene and Pliocene, similar climates and landscapes to those of Australia and northern island groups, and highly invasible terrain, permitted dispersal of woody plants. Cooling climates and formation of a more mountainous, more compact landscape after that time reduced dispersal of woody plants and favoured herbaceous, wetland and highly dispersible plant groups. The prominence of dispersal has led to intense selective immigration, and is responsible for many characteristic features of the flora. Species selection by glacial–interglacial cycles has restricted acquisition or retention of cool or arid climate adaptations, particularly in the lowland flora. Endemic and range disjunction patterns in the New Zealand mainland are not, in general, directly caused by Pliocene inundations or the faulting and associated horizontal displacement of terrain that has continued since the Miocene. They have arisen mainly through Pleistocene extinctions, speciation and dispersal, and some patterns are strongly linked to repeated glaciation. Endemic centres are associated with differentiated terrain and climates providing isolation, distinctive environments, and habitat continuity conducive to speciation. [ABSTRACT FROM AUTHOR]

Abstract Aim Fossil pollen preserved within small salt lake basins in the Australian interior is used to reconstruct mid- to late Holocene vegetation. The study aims to identify the origin of problems such as woodland decline and salinization within present ecosystems. Location Warrananga and Tooperoopna salt lakes, south-western New South Wales, Australia. Methods Pollen, carbonized particle and sedimentological analyses of cores taken from salt lakes. Results Prior to c . 4500 years ago, the region supported a dense cover of Casuarinaceae woodlands. It is possible that the subhumid zone species Allocasuarina luehmannii comprised some of the Casuarinaceae element. In the late Holocene, A. luehmannii disappeared from the record and chenopodiaceous low shrublands expanded. About 2000 years ago, Callitris representation decreased. Woodland contraction also occurred after European settlement. Main conclusions Increasing aridity or greater seasonal variation in the climate during the late Holocene caused a contraction of woodland vegetation. Increased proportions of Chenopodiaceae may indicate soil salinization around the basins. A decrease in Callitris was possibly due to heightened severity or frequency of drought events after 2000 years ago. Decline in woodland pollen in the uppermost samples is explained by the preferential clearing of Callitris glaucophylla , Callitris gracilis and Casuarina pauper for timber and their limited regeneration because of browsing by stock and rabbits. [ABSTRACT FROM AUTHOR]

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