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Wetland methane (CH4) fluxes are highly variable over spatial and temporal scales due to variations in CH4 production, oxidation, and transport. While some aspects of temporal variability in CH4 fluxes are well documented, diel variability is poorly constrained, and studies report conflicting findings, making it difficult to generalize. Topographic, geochemical, hydroclimatic, and vegetative variability can result in characteristically different "patches" that likely influence differences in diel patterns. We investigated diel patterns of CH4 fluxes from a large seasonal‐mineral soil wetland in Maryland (USA) across three functionally unique patches: two with vegetation (emergent and submerged aquatic vegetation) and one without (open water) during the summer of 2021. To explore the relationships between vegetation, environmental conditions, and flux patterns, we also measured physiochemical variables (air and water temperature, pH, relative humidity, PAR, dissolved oxygen, and water depth). To our knowledge, this is the first study comparing diel variability using chambers across such distinct vegetation patch types. We found that diel patterns were strongly linked to patch types: CH4 fluxes from the emergent vegetation did not display a consistent diel pattern, while fluxes from the submerged vegetation and no vegetation patches frequently peaked at 13:00 and 05:00, respectively. These differences could be a direct result of vegetation impact on production, oxidation, and/or transport of CH4 or on conditions covarying with patch type. This study contributes to the growing understanding of how CH4 fluxes vary spatially over diel cycles and emphasizes the importance of considering spatially varying diel patterns when estimating fluxes. Plain Language Summary: Methane (CH4) emissions from wetlands are known to vary over space and time, to be largely controlled by vegetation, and exhibit strong seasonal patterns. Yet daily patterns are not well characterized due to the limited number of studies and to difficulties in obtaining nighttime measurements. To address this, we investigated CH4 flux patterns over day and night cycles in patches characterized by emergent, submerged, or no vegetation in a temperate freshwater herbaceous wetland. We show that daily patterns of CH4 emissions are strongly linked to the type of vegetation present but the mechanistic influence of plants on production and consumption is unclear. This work contributes to the growing understanding of how CH4 varies within wetland landscapes over time. Key Points: Vegetation presence and type can control day and nighttime methane (CH4) fluxesPatterns in CH4 flux over diel cycles and across vegetation patch types vary such that a single daily measurement may not adequately capture variability of diel fluxesVegetation function that facilitates both production and oxidation of CH4 can lead to unpredictable diel patterns in CH4 flux [ABSTRACT FROM AUTHOR]

Methane (CH4) dynamics in wetlands are spatially variable and difficult to estimate at ecosystem scales. Patches with different plant functional types (PFT) represent discrete units within wetlands that may help characterize patterns in CH4 variability. We investigate dissolved porewater CH4 concentrations, a representation of net CH4 production and potential source of atmospheric flux, in five wetland patches characterized by a dominant PFT or lack of plants. Using soil, porewater, and plant variables we hypothesized to influence CH4, we used three modeling approaches—Classification and regression tree, AIC model selection, and Structural Equation Modeling—to identify direct and indirect influences on porewater CH4 dynamics. Across all three models, dissolved porewater CO2 concentration was the dominant driver of CH4 concentrations, partly through the influence of PFT patches. Plants in each patch type likely had variable influence on CH4 via root exudates (a substrate for methanogens), capacity to transport gas (both O2 from and CH4 to the atmosphere), and plant litter quality which impacted soil respiration and production of CO2 in the porewater. We attribute the importance of CO2 to the dominant methanogenic pathway we identified, which uses CO2 as a terminal electron acceptor. We propose a mechanistic relationship between PFT patches and porewater CH4 dynamics which, when combined with sources of CH4 loss including methanotrophy, oxidation, or plant‐mediated transport, can provide patch‐scale estimates of CH4 flux. Combining these estimates with the distribution of PFTs can improve ecosystem CH4 flux estimates in heterogenous wetlands and improve global CH4 budgets. Plain Language Summary: Methane is a potent greenhouse gas and understanding what controls methane production from microbes to plant communities can improve our estimates of wetland fluxes and global methane budgets. We propose characterizing methane dynamics in herbaceous wetlands at the scale of plant patches as patches integrate multiple local properties, are generally discrete, and relatively easy to map and measure. To characterize common wetland patch types, we investigate patterns of dissolved methane, soil biogeochemistry, and plant properties in 4 vegetated (submerged vegetation, forb, grass, and sedge) and 1 unvegetated wetland patch types in a temperate, freshwater, herbaceous wetland. We found that methane production differs significantly across patches and is largely correlated with each plant's capacity to transport gas to and from the soil, the quality of plant litter, and the properties of dissolved organic carbon in each patch. This work improves our understanding of how patches uniquely influence methane and by mapping the distribution of these patches we can improve our estimates of wetland methane fluxes. Key Points: Herbaceous plant patches present a unit of measure that can integrate multiples scales controlling wetland methane dynamicsMethane dynamics in the soil are linked to plant‐mediated rhizosphere oxygenation, litter quality, and DOC compositionGrass and sedge functional types seem to modulate methane via different mechanisms, highlighting the importance of using functional type [ABSTRACT FROM AUTHOR]

Para football is currently played in impairment-specific formats by thousands of people worldwide. To date, there have been no prospective longitudinal injury surveillance studies. This study aimed to implement a prospective injury surveillance study within elite English Para football and analyse the injury risk within the England Blind and Cerebral Palsy (CP) squads. Match and training injury data based on a 'time loss' definition were collected and analysed for each squad including incidence per 1,000 player hours, severity, injury location and associated event of injury. Injury incidence were lower in training than matches (CP 67.6/1000 player match hours (CI 33.8–135.2) and 5.7/1000 training hours (CI 3.8–8.7) and Blind 44.0/1000 player match hours (CI 26.1–74.3) and 5.5/1000 training hours (CI 3.5–8.6). Training injuries were more severe than match injuries across both squads (CP median 12 days lost in matches and 16 training and Blind median days 5 matches and 12 training). 73% Blind and 74% CP footballer injuries were to the lower limb and 17% head and neck equally across both Para football squads. 'Muscle and tendon injuries' (51%) represented the greatest proportion of injuries for CP footballers, and 'joint (non-bone)/ligament injuries' (43%) for Blind footballers. Collaboration and implementation of higher quality surveillance methodology and data collection in Para sport with greater athlete numbers are needed to inform injury prevention strategies. [ABSTRACT FROM AUTHOR]

Objectives: The Professional Rugby Injury Surveillance Project is the largest and longest running rugby union injury surveillance project globally and focuses on the highest level of rugby in England.Methods: We examined match injuries in professional men's rugby over the period 2002/2003 to 2018/2019 and described trends in injuries over this time.Results: Over the period 2002/2003-2018/2019, 10 851 injuries occurred in 1 24 952 hours of match play, equating to a mean of 57 injuries per club per season and one injury per team per match. The mean incidence, severity (days absence) and burden (days absence/1000 hours) of injury were 87/1000 hours (95% CI 82 to 92), 25 days (95% CI 22 to 28) and 2178 days/1000 hours (95% CI 1872 to 2484), respectively. The tackle accounted for 43% injuries with running the second most common activity during injury (12%). The most common injury location was the head/face with an incidence of 11.3/1000 hours, while the location with the highest overall burden was the knee (11.1 days/1000 hours). Long-term trends demonstrated stable injury incidence and proportion of injured players, but an increase in the mean and median severity of injuries. Concussion incidence, severity and burden increased from the 2009/2010 season onwards and from 2011 to 2019 concussion was the most common injury.Conclusion: The rise in overall injury severity and concussion incidence are the most significant findings from this work and demonstrate the need for continued efforts to reduce concussion risk as well as a greater understanding of changes in injury severity over time. [ABSTRACT FROM AUTHOR]

This study aimed to describe anthropometry and incidence, nature and causes of match injuries in women's international rugby sevens and to compare these with results reported previously for men's international rugby sevens. The study comprised an 8-season, prospective study of World Rugby's women's Sevens World Series. Over the eight seasons, the overall incidence of injury was 105.6 (95% CI: 96.0 to 116.3) injuries/1000 player-match-hours with a mean injury severity of 53.4 (95% CI: 46.9 to 59.9) days-absence. There were no statistically significant trends for backs or forwards in the incidence (backs: p = 0.470; forwards: p = 0.242) or mean severity (backs: p = 0.098; forwards: p = 0.544) of injuries sustained over the 8-season period. Head/face (20.8%), knee (19.7%), ankle (11.3%) and shoulder/clavicle (8.4%) were the most common injury locations while ligament sprain (31.7%), concussion (15.6%), haematoma/bruise (11.5%) and fracture (11.5%) were the most common types of injury sustained. Being-tackled (35.4%), tackling (26.3%), collisions (13.8%) and rucks (8.8%) were the match events responsible for most injuries. The study indicates that injury burden in women's international rugby sevens (5,640 days-absence/1000 player-match-hours; 95% CI: 5,123 to 6,209) is similar to that reported previously for men's international rugby sevens (5,263 days-absence/1000 player-match-hours; 95% CI: 5,000 to 5,540). [ABSTRACT FROM AUTHOR]

Rugby union is a popular team sport that demands high levels of physical fitness and skill. The study aim was to examine trends in training volume and its impact on injury incidence, severity and burden over an 11-season period in English professional rugby. Data were recorded from 2007/08 through 2017/18, capturing 1,501,606 h of training exposure and 3,782 training injuries. Players completed, on average, 6 h 48 minutes of weekly training (95% CI: 6 h 30 mins to 7 h 6 mins): this value remained stable over the 11 seasons. The mean incidence of training-related injuries was 2.6/1000 player-hours (95% CI: 2.4 to 2.8) with a mean severity rising from 17 days in 2007/08 to 37 days in 2017/18 (Change/season = 1.773, P <0.01). Rate of change in severity was dependent on training type, with conditioning (non-gym-based) responsible for the greatest increase (2.4 days/injury/season). As a result of increasing severity, injury burden rose from 51 days absence/1000 player-hours in 2007/08 to 106 days' absence/1000 player-hours in 2017/18. Despite the low incidence of injury in training compared to match-play, training accounted for 34% of all injuries. Future assessments of training intensity may lead to a greater understanding of the rise in injury severity. [ABSTRACT FROM AUTHOR]

The aim of this study was to define the incidence and nature of match injuries sustained in men’s international under-20 rugby. The study comprised an 8-season prospective study of 16 international under-20 rugby tournaments. Procedures complied with the consensus statement for epidemiological studies in rugby. Outputs included players’ mean age, stature and body mass and incidence, severity, location, type and cause of match injuries. The overall incidence of injury was 49.7 injuries/1000 player-match-hours (backs: 48.3; forwards: 50.9) with a mean severity of 32.2 days-absence (backs: 29.4; forwards: 34.4). There were no significant changes in incidence or severity of injury over the study period. Shoulder/clavicle (18.3%), head/face (16.4%), knee (13.7%) and ankle (13.7%) were the most common injury locations and ligament sprain (35.4%), haematoma/bruise (15.9%), concussion (12.5%) and muscle strain (11.2%) the most common types of injury. Being-tackled (29.2%), tackling (24.0%) and collisions (14.3%) were the most common events leading to injury. The results confirm that international under-20 rugby has a high incidence and severity of injury but the incidence is half that reported for senior international players. There was no significant change in the overall incidence of injury at the Under-20 level in the period 2008 to 2016. [ABSTRACT FROM AUTHOR]