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Aim: To quantify the impact of the 2019-2020 megafires on Australian plant diversity by assessing burnt area across 26,062 species ranges and the effects of fire history on recovery potential. Further, to exemplify a strategic approach to prioritizing plant species affected by fire for recovery actions and conservation planning at a national scale. Location: Australia. Methods: We combine data on geographic range, fire extent, response traits and fire history to assess the proportion of species ranges burnt in both the 2019-2020 fires and the past. Results: Across Australia, suitable habitat for 69% of all plant species was burnt (17,197 species) by the 2019-2020 fires and herbarium specimens confirm the presence of 9,092 of these species across the fire extent since 1950. Burnt ranges include those of 587 plants listed as threatened under national legislation (44% of Australia's threatened plants). A total of 3,998 of the 17,197 fire-affected species are known to resprout after fire, but at least 2,928 must complete their entire life cycle - from germinant to reproducing adult - prior to subsequent fires, as they are killed by fire. Data on previous fires show that, for 257 species, the historical intervals between fire events across their range are likely too short to allow regeneration. For a further 411 species, future fires during recovery will increase extinction risk as current populations are dominated by immature individuals. Main conclusion: Many Australian plant species have strategies to persist under certain fire regimes, and will recover given time, suitable conditions and low exposure to threats. However, short fire intervals both before and after the 2019-2020 fire season pose a serious risk to the recovery of at least 595 species. Persistent knowledge gaps about species fire response and post-fire population persistence threaten the effective long-term management of Australian vegetation in an increasingly pyric world.

We introduce the AusTraits database - a compilation of values of plant traits for taxa in the Australian flora (hereafter AusTraits). AusTraits synthesises data on 448 traits across 28,640 taxa from field campaigns, published literature, taxonomic monographs, and individual taxon descriptions. Traits vary in scope from physiological measures of performance (e.g. photosynthetic gas exchange, water-use efficiency) to morphological attributes (e.g. leaf area, seed mass, plant height) which link to aspects of ecological variation. AusTraits contains curated and harmonised individual- and species-level measurements coupled to, where available, contextual information on site properties and experimental conditions. This article provides information on version 3.0.2 of AusTraits which contains data for 997,808 trait-by-taxon combinations. We envision AusTraits as an ongoing collaborative initiative for easily archiving and sharing trait data, which also provides a template for other national or regional initiatives globally to fill persistent gaps in trait knowledge., Measurement(s)plant traitTechnology Type(s)digital curationSample Characteristic - OrganismViridiplantaeSample Characteristic - LocationAustralia Machine-accessible metadata file describing the reported data: 10.6084/m9.figshare.14545755

Questions: The taxonomic and functional composition of plant communities captures different dimensions of diversity. Functional diversity (FD) - as calculated from species traits - typically increases with species richness in communities and is expected to be higher in less extreme environments, where a broader range of functional strategies can persist. Further, woody and herbaceous plant families may contribute disproportionately to FD in different bioregions. To build an understanding of these questions using Australia as a case study, we aimed to quantify how FD varies: (a) with species richness, (b) with climate, and (c) between major plant families representing different growth forms. Location: Australia. Methods: Data on species distribution and functional traits for 14,003 species were combined and FD approximated using hypervolumes (i.e. multidimensional species assemblage trait niche) based on three traits key to understanding plant ecological strategies: leaf size, seed mass and adult height. Plant assemblage hypervolumes were calculated including all species with suitable habitat in each 10 в 10 km grid cell across Australia, and in each of 85 bioregions. Within bioregions FD was also calculated separately for a suite of largely woody and herbaceous plant families. Relationships between FD, species richness and climate were explored. Results: As predicted, FD was positively related to species richness and annual precipitation, and negatively related to summer maximum temperature, both in analyses of 10 km в 10 km grid cells and of bioregions (all p Conclusions: Strong links between FD and climate could mean significant shifts in the FD of ecosystems with climate change. Monitoring changes in FD and associated ecosystem functions requires a detailed understanding of FD, which we begin to develop in this study.

1. While theoretical models predict reproductive allocation (RA) should approach 100% of available energy as a plant ages, available empirical data suggest much lower RA values in perennial plants. ...

The muon-to-electron conversion experiment (Mu2e) at Fermilab is designed to explore charged lepton flavor violation. It is composed of three large superconducting solenoids: the production solenoid, the transport solenoid (TS), and the detector solenoid. The TS is formed by two magnets: TS upstream and TS downstream. Each has its own cryostat and power supply. Tolerance sensitivity studies of the position and angular alignment of each coil in this magnet system were performed in the past with the objective to demonstrate that the magnet design meets all the field requirements. The alignment of the cold masses is critical to maximize the transmission of muons and to avoid possible backgrounds that would reduce the sensitivity of the experiment. Each TS magnet cold mass can be individually aligned. In this paper, we discuss the implications of the alignment of the TS cold masses in terms of the displacement of the magnetic center. Consideration of the practical mechanical limits is also presented.

A plant's reproductive allocation (RA) schedule describes the fraction of surplus energy allocated to reproduction as it increases in size. While theorists use RA schedules as the connection between life history and energy allocation, little is known about RA schedules in real vegetation. Here we review what is known about RA schedules for perennial plants using studies either directly quantifying RA or that collected data from which the shape of an RA schedule can be inferred. We also briefly review theoretical models describing factors by which variation in RA may arise. We identified 34 studies from which aspects of an RA schedule could be inferred. Within those, RA schedules varied considerably across species: some species abruptly shift all resources from growth to reproduction; most others gradually shift resources into reproduction, but under a variety of graded schedules. Available data indicate the maximum fraction of energy allocated to production ranges from 0.1 to 1 and that shorter lived species tend to have higher initial RA and increase their RA more quickly than do longer‐lived species. Overall, our findings indicate, little data exist about RA schedules in perennial plants. Available data suggest a wide range of schedules across species. Collection of more data on RA schedules would enable a tighter integration between observation and a variety of models predicting optimal energy allocation, plant growth rates, and biogeochemical cycles.

Plant species differ in the amounts of energy allocated to different reproductive tissues, driving differences in their ecology and energy flows within ecosystems. While it is widely agreed that energy allocation is key to reproductive outcomes, few studies have estimated how reproductive effort (RE) is partitioned among different pools, for multiple species in a community. In plants, RE can be partitioned in several meaningful ways: seed versus non-seed tissues; into flowers that form seeds and those that fail to develop; into pre-versus post-pollination tissues, and into successful versus aborted ovules. Evolutionary theory suggests several hypotheses about how these tissues should be coordinated across species. To quantify variation in allocation to different reproductive tissues, we collected detailed RE measurements for a year from 14 perennial species in a recurrent-fire coastal heath community in eastern Australia. Overall we found that total accessory costs – the proportion of RE not directly invested in provisioning the seed – were very large, varying from 95.8% to 99.8% across the study species. These results suggest that studies using seed or fruit production as measures of RE may underestimate it by 10-to 500-fold. We propose a suitable alternative that well-approximates true RE. When comparing species, we found strong support for three evolutionary trade-offs that are predicted to arise when a given energy pool is divided into different tissue masses and counts across species: 1) between successful pollen-attraction costs and mature ovule count, 2) between total reproductive costs and seed count, and 3) between seedset and relative investment in pollen-attraction costs. As a result of these trade-offs, species were also predicted to show coordinated shifts in the amounts invested in floral construction, in seedset and seed size. These shifts in investment were indeed observed, with the amount allocated to discarded tissues increasing with seed size and the amount allocated to pollen-attraction decreasing with seed size. It is already well-established that the seed size axis aligns with the colonization-competition life history spectrum; here we show that relative construction costs of pollen-attraction versus provisioning tissues and seedset are also part of this trajectory, expanding our understanding of the relatives sizes of floral and fruiting structures observed across angiosperms.

Species distributions may be limited by substrate boundaries due to constraints at either the germination or seedling establishment life history stages. In a community of alpine tundra plants from the Sierra Nevada, some species are widespread, occurring across all four substrates studied: diorite, granite, hornfels, and marble. Other species are restricted to fewer soil types. We collected seeds from 12 species and performed a reciprocal transplant experiment in growth chambers using native soils. Eleven species germinated and established equally well across all soil types, indicating substrate chemistry did not alone determine species field distributions. However, two patterns emerged that may contribute to our understanding of species composition and dominance across substrates. First, species more dominant on the drier substrates reached at least half their total germination within two weeks of planting. Species more dominant on the wetter substrates required a longer period in wet soil to ge...

To investigate how seed reserves affect early seedling performance, we conducted a factorial greenhouse experiment using Lithocarpus densiflora (Tanoak). Seedlings were grown from large (5.8+/-0.7 g) and small (3.2+/-0.4 g) seeds and, following shoot emergence, seeds were either removed or left attached. Seedlings were harvested for quantification of biomass and delta13C at seven time periods following seed removal (2, 4, 8, 16, 32, 64, 128 days) and seedling photosynthesis was measured three separate time periods (2-4, 49-82, 95-128 days after seed removal). Biomass increased for all seedlings, but the increase was significantly larger for seedlings with attached seeds than with removed seeds. Seed removal just after shoot emergence significantly decreased seedling biomass, but seed removal 64 days after shoot emergence had no effect on seedling biomass. Seedling photosynthesis per unit leaf area varied by time and seed presence, but not by seed size. At the first period, seedlings with attached seeds had significantly higher photosynthetic rates than seedlings with removed seeds, at the second period there was no effect of seed removal, and at the third time period seedlings with attached seeds had significantly lower photosynthetic rates than seedlings with removed seeds. Despite temporal variation in photosynthesis per unit leaf area, seedlings with attached seeds always had significantly greater leaf area than seedlings with removed seeds, resulting in significantly higher total plant photosynthesis at all three time periods. The delta13C values of both the leaves and roots were more similar to that of the seed for seedlings with attached seeds than for seedlings with removed seeds, however, seed removal and seed size strongly affected root delta13C. This study demonstrates that seed reserves have important effects on the early growth, physiology, and delta13C of L. densiflora seedlings.

In a Namib population of the dioecious perennial Acanthosicyos horrida Welw. ex Hook. f. in which fruit production is declining, we investigated the effects of plant gender, plant size, and subpopulation elevation (a proxy of water availability) on a plant's biomass allocation to sexual reproduction. While males invested more heavily in buds and flowers than females, females allocated 10 times more total biomass to reproduction per m3 of vegetation than males during our survey period. Also, smaller plants, particularly females, allocated more biomass to reproduction per m3 of vegetation than larger plants. This result suggests that plant fecundity per m3 of vegetation decreases with plant size. Aging of the population could thus be a cause of the reduced fruit production; however, we found that the population was skewed towards the smallest size classes. On the other hand, the fact that plants in the subpopulation at higher elevation above the river were only six percent as productive as plants in the subpopulation at low elevation suggests that the depth of the water table may be critical to fruit production and that a reduced groundwater level caused by nearby urbanisation could have long term effects on harvests.

In monospecific stands of Acacia drepanolobium in Laikipia, Kenya, virtually all but the smallest trees are occupied by one of four species of ants. Although trees are a limiting resource, all four ant species are maintained in this system. Three separate lines of evidence confirm a linear dominance hierarchy among these four ants: (1) experimentally staged conflicts, (2) natural transitions among 1773 tagged trees over a 6-month period, and (3) the average sizes of trees occupied by ants of different species. Short-term dynamics during a drying period reveal that many smaller trees (1 m) occupied by dominant ants were subsequently abandoned, and that abandoned trees had grown more slowly than those that were not abandoned. Height growth increments over 6 months were generally independent of ant occupant, but increased with tree height. Among taller trees (1 m), changes in ant occupation congruent with the dominance hierarchy (i.e., transitions from more subordinate ant species to more dominant ant species) occurred on trees that grew faster than average. In contrast, the (less frequent) changes in ant occupation "against" the direction of the dominance hierarchy occurred on trees that grew more slowly than average. Observed correlations between tree vigor and takeover direction suggest that colony growth of dominant ant species is either favored in more productive microhabitats, or that such colonies differentially seek out healthier trees for conquest. Colonies of dominant species may differentially abandon more slowly growing trees during (dry) periods of retrenchment, or suffer higher mortality on these trees. Subordinate ant species appear to move onto these abandoned trees and, to a lesser extent, colonize new recruits in the sapling class. These data reveal that within a simple linear dominance hierarchy, short-term variations exist that may reveal underlying mechanisms associated with coexistence.

Understanding how plants are constructed—i.e., how key size dimensions and the amount of mass invested in different tissues varies among individuals—is essential for modeling plant growth, carbon stocks, and energy fluxes in the terrestrial biosphere. Allocation patterns can differ through ontogeny, but also among coexisting species and among species adapted to different environments. While a variety of models dealing with biomass allocation exist, we lack a synthetic understanding of the underlying processes. This is partly due to the lack of suitable data sets for validating and parameterizing models. To that end, we present the Biomass And Allometry Database (BAAD) for woody plants. The BAAD contains 259 634 measurements collected in 176 different studies, from 21 084 individuals across 678 species. Most of these data come from existing publications. However, raw data were rarely made public at the time of publication. Thus, the BAAD contains data from different studies, transformed into standard units and variable names. The transformations were achieved using a common workflow for all raw data files. Other features that distinguish the BAAD are: (i) measurements were for individual plants rather than stand averages; (ii) individuals spanning a range of sizes were measured; (iii) plants from 0.01–100 m in height were included; and (iv) biomass was estimated directly, i.e., not indirectly via allometric equations (except in very large trees where biomass was estimated from detailed sub-sampling). We included both wild and artificially grown plants. The data set contains the following size metrics: total leaf area; area of stem cross-section including sapwood, heartwood, and bark; height of plant and crown base, crown area, and surface area; and the dry mass of leaf, stem, branches, sapwood, heartwood, bark, coarse roots, and fine root tissues. We also report other properties of individuals (age, leaf size, leaf mass per area, wood density, nitrogen content of leaves and wood), as well as information about the growing environment (location, light, experimental treatment, vegetation type) where available. It is our hope that making these data available will improve our ability to understand plant growth, ecosystem dynamics, and carbon cycling in the world's vegetation.

El trabajo se refiere a la estandarización del E.P.P.S., en una versión adaptada en 1969 en nuestro país, en una muestra de 4° año de Educación Media de la Región Metropolitana, compuesta tanto por varones como mujeres pertenecientes a los niveles socioeconómicos alto, medio y bajo.Los resultados permitieron obtener normas diferenciales por sexo y para dos agrupaciones de nivel socioeconómico: alto, medio y bajo.Estas normas se entregan en percentiles y en puntuaciones típicas normalizadas T.Se enfatiza la naturaleza ipsativa de las puntuaciones que arroja la prueba, especialmente en lo que se refiere a la interpretación de los puntajes.

Los psicólogos familiarizados con el campo de la evaluación psicológica a través de pruebas reconocen la importancia de poder disponer de normas obtenidas en nuestra realidad para usar con propiedad un instrumento psicológico. Cuando no se cuenta con un estudio de este tipo, se tendría que aceptar interpretar los resultados de las pruebas ya sea con normas que pertenecen a otros países u otras culturas - lo que desde el punto de vsita científico se fundamenta en una serie de supuestos que la mayoría de las veces no se cumplen - o considerar estos resultados de una forma más clínica, para la cual muchos instrumentos no se prestan, aparte de otras dificultades que se pueden persentar con este tipo de enfoque.