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Background and aimsTropical forests exchange more carbon dioxide (CO2) with the atmosphere than any other terrestrial biome. Yet, uncertainty in the projected carbon balance over the next century is roughly three-times greater for the tropics than other ecosystems. Our limited knowledge of tropical plant physiological responses, including photosynthetic, to climate change is a substantial source of uncertainty in our ability to forecast the global terrestrial carbon sink.MethodsWe used a meta-analytic approach, focusing on tropical photosynthetic temperature responses, to address this knowledge gap. Our dataset, gleaned from 18 independent studies, included leaf-level light saturated photosynthetic (Asat) temperature responses from 108 woody species, with additional temperature parameters (35 species) and rates (250 species) of both maximum rates of electron transport (Jmax) and Rubisco carboxylation (Vcmax). We investigated how these parameters responded to mean annual temperature (MAT), temperature variability, aridity, and elevation, as well as also how responses differed among successional strategy, leaf habit, and light environment.Key resultsOptimum temperatures for Asat (ToptA) and Jmax (ToptJ) increased with MAT but not for Vcmax (ToptV). Although photosynthetic rates were higher for "light" than "shaded" leaves, light conditions did not generate differences in temperature response parameters. ToptA did not differ with successional strategy, but early successional species had ~4 °C wider thermal niches than mid/late species. Semi-deciduous species had ~1 °C higher ToptA than broadleaf evergreen. Most global modeling efforts consider all tropical forests as a single "broadleaf evergreen" functional type, but our data show that tropical species with different leaf habits display distinct temperature responses that should be included in modeling efforts.ConclusionsThis novel research will inform modeling efforts to quantify tropical ecosystem carbon cycling and provide more accurate representations of how these key ecosystems will respond to altered temperature patterns in the face of climate warming.

Leaf-level gas exchange data support the mechanistic understanding of plant fluxes of carbon and water. These fluxes inform our understanding of ecosystem function, are an important constraint on parameterization of terrestrial biosphere models, are necessary to understand the response of plants to global environmental change, and are integral to efforts to improve crop production. Collection of these data using gas analyzers can be both technically challenging and time consuming, and individual studies generally focus on a small range of species, restricted time periods, or limited geographic regions. The high value of these data is exemplified by the many publications that reuse and synthesize gas exchange data, however the lack of metadata and data reporting conventions make full and efficient use of these data difficult. Here we propose a reporting format for leaf-level gas exchange data and metadata to provide guidance to data contributors on how to store data in repositories to maximize their discoverability, facilitate their efficient reuse, and add value to individual datasets. For data users, the reporting format will better allow data repositories to optimize data search and extraction, and more readily integrate similar data into harmonized synthesis products. The reporting format specifies data table variable naming and unit conventions, as well as metadata characterizing experimental conditions and protocols. For common data types that were the focus of this initial version of the reporting format, i.e., survey measurements, dark respiration, carbon dioxide and light response curves, and parameters derived from those measurements, we took a further step of defining required additional data and metadata that would maximize the potential reuse of those data types. To aid data contributors and the development of data ingest tools by data repositories we provided a translation table comparing the outputs of common gas exchange instruments. Extensive consultation with data collectors, data users, instrument manufacturers, and data scientists was undertaken in order to ensure that the reporting format met community needs. The reporting format presented here is intended to form a foundation for future development that will incorporate additional data types and variables as gas exchange systems and measurement approaches advance in the future. The reporting format is published in the U.S. Department of Energy's ESS-DIVE data repository, with documentation and future development efforts being maintained in a version control system.

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.

The "Australian Curriculum: Health and Physical Education" (Australian Curriculum, Assessment and Reporting Authority (2020a) requires all teachers to include Aboriginal and Torres Strait Islander peoples', culture and history where there is scope to meaningfully do so. However, there is a general absence in Australia and internationally of understanding culturally responsive pedagogy for those perspectives in teaching Physical Education (PE). This concept paper proposes an educational framework comprising Yunkaporta's (2009) 8 Ways Aboriginal Pedagogy and the Game Sense approach (GSA) (Australian Sports Commission [ASC], 1996). for games and sport teaching in PE to move towards a culturally responsive curriculum and pedagogy. We provide an empirical argument that curricula are instruments of colonisation and explain the creation of a cultural interface through games and sport as one approach for decolonising PE. We present an opportunity to 'close the gap' between Western and Aboriginal knowledge through the purposeful design of engagement in reconciliation, respect and recognition of continuous living Aboriginal cultures. We use the game Parndo (ASC, 2000) to illustrate an example of how Yunkaporta's (2009) framework and the GSA become a solution for closing our identified gap. By proposing a culturally responsive curriculum, we focus on the importance of identity for all people and how curricula must be relevant and meaningful for all Australians. Importantly, Yunkaporta's (2009) 8 Ways is a product of 'cultural interface', co-created through dialogue between Aboriginal and non-Aboriginal educators. Our findings, although not transferable to other settings, nonetheless have relevance to other countries where there is a similar move to decolonise PE curricula.

Assessment of physical literacy poses a dilemma of what instrument to use. There is currently no guide regarding the suitability of common assessment approaches. The purpose of this brief communication is to provide a user's guide for selecting physical literacy assessment instruments appropriate for use in school physical education and sport settings. Although recommendations regarding specific instruments are not provided, the guide offers information about key attributes and considerations for the use. A decision flow chart has been developed to assist teachers and affiliated school practitioners to select appropriate methods of assessing physical literacy. School physical education and sport scenarios are presented to illustrate this process. It is important that practitioners are empowered to select the most appropriate instrument/s to suit their needs.

Purpose: The development of a physical literacy definition and standards framework suitable for implementation in Australia. Method: Modified Delphi methodology. Results: Consensus was established on four defining statements: Core--Physical literacy is lifelong holistic learning acquired and applied in movement and physical activity contexts; Composition--Physical literacy reflects ongoing changes integrating physical, psychological, cognitive, and social capabilities; Importance--Physical literacy is vital in helping us lead healthy and fulfilling lives through movement and physical activity; and Aspiration--A physically literate person is able to draw on his/her integrated physical, psychological, cognitive, and social capacities to support health promoting and fulfilling movement and physical activity, relative to the situation and context, throughout the lifespan. The standards framework addressed four learning domains (physical, psychological, cognitive, and social), spanning five learning configurations/levels. Conclusion: The development of a bespoke program for a new context has important implications for both existing and future programs.

This article reports on a study that inquired into the journeys of sixteen Indigenous Australian athletes from their first touch of the footy to the Australian Football League (AFL) and National Rugby League (NRL) that identified two distinct stages of their journeys. These were: (1) the development of expertize and of a distinctly Aboriginal style of play from their first touch of a footy to around the age of thirteen and, (2) a process of cultural transitioning toward and into the AFL and NRL. This article takes an interdisciplinary approach to focus on the second stage of transitioning into the world of professional sport and sport as business. Identifying this as a process of cultural transitioning from local Aboriginal culture to the culture of professional sport provided insight into this transitioning process while illuminating the profound importance of culture in this process. It also helped identify the ways in which tensions between local approaches to 'footy' as play and cultural expression and professional sport as work, within the global culture of sport-as-business, were manifested in the challenges that the participants had to overcome. This article thus contributes to knowledge about Indigenous development of sporting expertize, of the specific challenges they face in transitioning into the global culture of commodified sport and how they succeed from a cultural perspective.

Forecasting the effects of climate change on nitrogen (N) cycling in pastures requires an understanding of changes in tissue N. We examined the effects of elevated atmospheric CO2 concentration, atmospheric warming and simulated grazing (clipping frequency) on aboveground and belowground tissue N concentrations and C : N ratios of a C3 pasture grass. Phalaris aquatica L. cv. 'Holdfast' was grown in the field in six transparent temperature gradient tunnels (18 × 1.5 × 1.5 m each), three at ambient atmospheric CO2 and three at 759 p.p.m. CO2. Within each tunnel, there were three air temperature treatments: ambient control, +2.2/+4.0 °C above ambient day/night warming and +3.0 °C continuous warming. A frequent and an infrequent clipping treatment were applied to each warming × CO2 combination. Green leaf N concentrations were decreased by elevated CO2 and increased by more frequent clipping. Both warming treatments increased leaf N concentrations under ambient CO2 concentrations, but did not significantly alter leaf N concentrations under elevated CO2 concentrations. Nitrogen resorption from leaves was decreased under elevated CO2 conditions as well as by more frequent clipping. Fine root N concentrations decreased strongly with increasing soil depth and were further decreased at the 10-60 cm soil depths by elevated CO2 concentrations. The interaction between the CO2 and warming treatments showed that leaf N concentration was affected in a non-additive manner. Changes in leaf C : N ratios were driven by changes in N concentration. Overall, the effects of CO2, warming and clipping treatments on aboveground tissue N concentrations were much greater than on belowground tissue.

Background: The need for rapid in-field measurement of key traits contributing to yield over many thousands of genotypes is a major roadblock in crop breeding. Recently, leaf hyperspectral reflectance data has been used to train machine learning models using partial least squares regression (PLSR) to rapidly predict genetic variation in photosynthetic and leaf traits across wheat populations, among other species. However, the application of published PLSR spectral models is limited by a fixed spectral wavelength range as input and the requirement of separate custom-built models for each trait and wavelength range. In addition, the use of reflectance spectra from the short-wave infrared region requires expensive multiple detector spectrometers. The ability to train a model that can accommodate input from different spectral ranges would potentially make such models extensible to more affordable sensors. Here we compare the accuracy of prediction of PLSR with various deep learning approaches and an ensemble model, each trained and tested using previously published data sets. Results: We demonstrate that the accuracy of PLSR to predict photosynthetic and related leaf traits in wheat can be improved with deep learning-based and ensemble models without overfitting. Additionally, these models can be flexibly applied across spectral ranges without significantly compromising accuracy. Conclusion: The method reported provides an improved prediction of wheat leaf and photosynthetic traits from leaf hyperspectral reflectance and do not require a full range, high cost leaf spectrometer. We provide a web service for deploying these algorithms to predict physiological traits in wheat from a variety of spectral data sets, with important implications for wheat yield prediction and crop breeding. [ABSTRACT FROM AUTHOR]

This leaf gas exchange protocol enables light or CO2 response curves using a LI-COR LI-6400 portable photosynthesis system. The protocol originates in PrometheusWiki (http://prometheuswiki.publish.csiro.au/) where it has been tested and verified, and has received favourable user reviews. This reformatted and non-editable version is published as a Gold Leaf Protocol. For the most current version, including any user-commentary updates, readers may view the live version of the protocol at http://bit.ly/PWLicorGold.

This article reports on an ongoing study that investigates the development of expertise in rugby league and Australian football by Indigenous Australians as a socially and culturally situated process of learning. Focused on the sampling phase of the Development Model of Participation in Sport (6-12 years of age), it combines narrative inquiry and grounded theory methodologies to identify the important role that participation in a range of different sports and in informal games plays in the participants' development of expertise, as a process of socialisation.

Leaf gas exchange measurements are an important tool for inferring a plant's photosynthetic biochemistry. In most cases, the responses of photosynthetic CO2 assimilation to variable intercellular CO2 concentrations (A/Ci response curves) are used to model the maximum (potential) rate of carboxylation by ribulose‐1,5‐bisphosphate carboxylase/oxygenase (Rubisco, Vcmax) and the rate of photosynthetic electron transport at a given incident photosynthetically active radiation flux density (PAR; JPAR). The standard Farquhar‐von Caemmerer‐Berry model is often used with default parameters of Rubisco kinetic values and mesophyll conductance to CO2 (gm) derived from tobacco that may be inapplicable across species. To study the significance of using such parameters for other species, here we measured the temperature responses of key in vitro Rubisco catalytic properties and gm in cotton (Gossypium hirsutum cv. Sicot 71) and derived Vcmax and J2000 (JPAR at 2000 µmol m−2 s−1 PAR) from cotton A/Ci curves incrementally measured at 15°C–40°C using cotton and other species‐specific sets of input parameters with our new automated fitting R package 'OptiFitACi'. Notably, parameterisation by a set of tobacco parameters produced unrealistic J2000:Vcmax ratio of <1 at 25°C, two‐ to three‐fold higher estimates of Vcmax above 15°C, up to 2.3‐fold higher estimates of J2000 and more variable estimates of Vcmax and J2000, for our cotton data compared to model parameterisation with cotton‐derived values. We determined that errors arise when using a gm,25 of 2.3 mol m−2 s−1 MPa−1 or less and Rubisco CO2‐affinities in 21% O2 (KC21%O2) at 25°C outside the range of 46–63 Pa to model A/Ci responses in cotton. We show how the A/Ci modelling capabilities of 'OptiFitACi' serves as a robust, user‐friendly, and flexible extension of 'plantecophys' by providing simplified temperature‐sensitivity and species‐specificity parameterisation capabilities to reduce variability when modelling Vcmax and J2000. Summary statement: This manuscript demonstrates the importance of species‐specific parameterisation of A/Ci response models for accurate modelling of key photosynthetic parameters in cotton (Gossypium hirsutum). [ABSTRACT FROM AUTHOR]