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The density of wood is a key indicator of the carbon investment strategies of trees, impacting productivity and carbon storage. Despite its importance, the global variation in wood density and its environmental controls remain poorly understood, preventing accurate predictions of global forest carbon stocks. Here we analyse information from 1.1 million forest inventory plots alongside wood density data from 10,703 tree species to create a spatially explicit understanding of the global wood density distribution and its drivers. Our findings reveal a pronounced latitudinal gradient, with wood in tropical forests being up to 30% denser than that in boreal forests. In both angiosperms and gymnosperms, hydrothermal conditions represented by annual mean temperature and soil moisture emerged as the primary factors influencing the variation in wood density globally. This indicates similar environmental filters and evolutionary adaptations among distinct plant groups, underscoring the essential role of abiotic factors in determining wood density in forest ecosystems. Additionally, our study highlights the prominent role of disturbance, such as human modification and fire risk, in influencing wood density at more local scales. Factoring in the spatial variation of wood density notably changes the estimates of forest carbon stocks, leading to differences of up to 21% within biomes. Therefore, our research contributes to a deeper understanding of terrestrial biomass distribution and how environmental changes and disturbances impact forest ecosystems.

Aim: Ecological and anthropogenic factors shift the abundances of dominant and rare tree species within local forest communities, thus affecting species composition and ecosystem functioning. To inform forest and conservation management it is important to understand the drivers of dominance and rarity in local tree communities. We answer the following research questions: (1) What are the patterns of dominance and rarity in tree communities? (2) Which ecological and anthropogenic factors predict these patterns? And (3) what is the extinction risk of locally dominant and rare tree species?. Location: Global. Time period: 1990–2017. Major taxa studied: Trees. Methods: We used 1.2 million forest plots and quantified local tree dominance as the relative plot basal area of the single most dominant species and local rarity as the percentage of species that contribute together to the least 10% of plot basal area. We mapped global community dominance and rarity using machine learning models and evaluated the ecological and anthropogenic predictors with linear models. Extinction risk, for example threatened status, of geographically widespread dominant and rare species was evaluated. Results: Community dominance and rarity show contrasting latitudinal trends, with boreal forests having high levels of dominance and tropical forests having high levels of rarity. Increasing annual precipitation reduces community dominance, probably because precipitation is related to an increase in tree density and richness. Additionally, stand age is positively related to community dominance, due to stem diameter increase of the most dominant species. Surprisingly, we find that locally dominant and rare species, which are geographically widespread in our data, have an equally high rate of elevated extinction due to declining populations through large-scale land degradation. Main conclusions: By linking patterns and predictors of community dominance and rarity to extinction risk, our results suggest that also widespread species should be considered in large-scale management and conservation practices.

Forests are a substantial terrestrial carbon sink, but anthropogenic changes in land use and climate have considerably reduced the scale of this system1. Remote-sensing estimates to quantify carbon losses from global forests2-5 are characterized by considerable uncertainty and we lack a comprehensive ground-sourced evaluation to benchmark these estimates. Here we combine several ground-sourced6 and satellite-derived approaches2,7,8 to evaluate the scale of the global forest carbon potential outside agricultural and urban lands. Despite regional variation, the predictions demonstrated remarkable consistency at a global scale, with only a 12% difference between the ground-sourced and satellite-derived estimates. At present, global forest carbon storage is markedly under the natural potential, with a total deficit of 226 Gt (model range = 151-363 Gt) in areas with low human footprint. Most (61%, 139 Gt C) of this potential is in areas with existing forests, in which ecosystem protection can allow forests to recover to maturity. The remaining 39% (87 Gt C) of potential lies in regions in which forests have been removed or fragmented. Although forests cannot be a substitute for emissions reductions, our results support the idea2,3,9 that the conservation, restoration and sustainable management of diverse forests offer valuable contributions to meeting global climate and biodiversity targets.

Understanding what controls global leaf type variation in trees is crucial for comprehending their role in terrestrial ecosystems, including carbon, water and nutrient dynamics. Yet our understanding of the factors influencing forest leaf types remains incomplete, leaving us uncertain about the global proportions of needle-leaved, broadleaved, evergreen and deciduous trees. To address these gaps, we conducted a global, ground-sourced assessment of forest leaf-type variation by integrating forest inventory data with comprehensive leaf form (broadleaf vs needle-leaf) and habit (evergreen vs deciduous) records. We found that global variation in leaf habit is primarily driven by isothermality and soil characteristics, while leaf form is predominantly driven by temperature. Given these relationships, we estimate that 38% of global tree individuals are needle-leaved evergreen, 29% are broadleaved evergreen, 27% are broadleaved deciduous and 5% are needle-leaved deciduous. The aboveground biomass distribution among these tree types is approximately 21% (126.4 Gt), 54% (335.7 Gt), 22% (136.2 Gt) and 3% (18.7 Gt), respectively. We further project that, depending on future emissions pathways, 17-34% of forested areas will experience climate conditions by the end of the century that currently support a different forest type, highlighting the intensification of climatic stress on existing forests. By quantifying the distribution of tree leaf types and their corresponding biomass, and identifying regions where climate change will exert greatest pressure on current leaf types, our results can help improve predictions of future terrestrial ecosystem functioning and carbon cycling.

Determining the drivers of non-native plant invasions is critical for managing native ecosystems and limiting the spread of invasive species1,2. Tree invasions in particular have been relatively overlooked, even though they have the potential to transform ecosystems and economies3,4. Here, leveraging global tree databases5-7, we explore how the phylogenetic and functional diversity of native tree communities, human pressure and the environment influence the establishment of non-native tree species and the subsequent invasion severity. We find that anthropogenic factors are key to predicting whether a location is invaded, but that invasion severity is underpinned by native diversity, with higher diversity predicting lower invasion severity. Temperature and precipitation emerge as strong predictors of invasion strategy, with non-native species invading successfully when they are similar to the native community in cold or dry extremes. Yet, despite the influence of these ecological forces in determining invasion strategy, we find evidence that these patterns can be obscured by human activity, with lower ecological signal in areas with higher proximity to shipping ports. Our global perspective of non-native tree invasion highlights that human drivers influence non-native tree presence, and that native phylogenetic and functional diversity have a critical role in the establishment and spread of subsequent invasions.

This study was focused on assessing the phytoremediation potentials of some selected plant species on crude oil contaminated soils. Five plant species were cultivated in soils polluted with crude oil at 10, 50, 100, 150 and 200 mg kg-1. The results revealed that there were significant reduction in THC contents of soil ameliorated with the various plants species compared to the control group increases with increasing concentration of crude oil pollutant in soil. THC was 62.24 mg kg-1, 1,120 mg kg-1, 208.67 mg kg-1, 257.87 mg kg-1 and 2,762.79 mg kg-1 for R. simplex, P. balfouriana, K. pinnata, P. fruiticosa and T. spathecea plant species respectively. Results of phyto-extraction of heavy metals by the plant species showed increasing concentration with increasing volume of crude oil pollutant. Nickel concentration ranged from 0.05 mg kg-1 in K. pinnata to 0.43 mg kg-1 in P. fruiticosa. Copper concentration varied from 2.28 mg kg-1 in T. spathecea to 12.64 mg kg-1 in R. simplex. Iron concentration by the plants varied from 11.36 mg kg-1 in P. balfouriana to 24 mg kg-1 in K. pinnata. The concentration of Chromium from the soil by the plant species increased from 0.16 mg kg-1 in R. simplex to 0.38 mg kg-1. Zinc concentration varied from 2.64 mg l-1 K. pinnata to 10.26 mg kg-1 in R. simplex. The uptake of manganese by the plant species increased from 5.56 mg kg-1 in P. balfouriana to 10.56 mg kg-1 in T. spathecea while cobalt decreased from 0.08 mg kg-1 in T. spathecea to 0.001 mg kg-1 in R. simplex. The concentretion of lead ranged significantly from 0.01 mg kg-1 in K. pinnata to 0.82 mg kg-1 in P. fruiticosa. The study advocated for the use of phytoremediation with P. balfouriana and T. spathecea plant species.

The restoration of the endangered Korean fir (Abies koreana E.H.Wilson) forests requires mass production of high-quality and well-developed seedlings for outplanting. However, phytopathogenic fungal infections lower the survival rate and growth vigor of A. koreana seedlings, frustrating the re-afforestation efforts. This study isolated and identified the phytopathogenic fungi causing seedling blight and wilt diseases in A. koreana seedlings and investigated the potential of Bacillus velezensis CE 100 in controlling the fungal pathogens and promoting seedling growth. Phomopsis mali and Fusarium oxysporum were confirmed as the causal agents of blight and wilt diseases, respectively, and both fungi reduced the survival rate of A. koreana seedlings. B. velezensis CE 100 produced cell wall-degrading enzymes: chitinase, protease, and β-1,3-glucanase, and the bacterial crude enzyme fraction inhibited the spore germination and mycelial growth of P. mali and F. oxysporum in a concentration-dependent manner, causing severe morphological deformations. Consequently, treatment with B. velezensis CE 100 improved the survival rate of seedlings infected with either P. mali or F. oxysporum compared to the control and PB media treatment. The bacterium also increased nutrient availability through ammonia–nitrogen production and phosphate solubilization and produced indole-3-acetic acid (IAA), and its inoculation remarkably improved seedling growth (root and shoot dry weight) compared to the control and PB media treatment group. This is the first study to report P. mali and F. oxysporum as the pathogens causing seedling blight and wilt diseases in A. koreana nursery seedling, and the possibility of using B. velezensis CE 100 to control the fungal pathogens and improve the seedling growth without chemical use.

Cherry leaf spot (CLS) disease is one of the most common and deleterious disease of flowering cherry seedlings which lowers frost tolerance, growth, and biomass production during the season, and reduces flower production in following season. This study isolated two phytopathogens, Alternaria alternata CH3 and Alternaria alternata CH10, and confirmed their pathogenicity of CLS disease in flowering cherry seedlings, causing brownish spots and necrotic lesions on the leaves. We also isolated a plant growth-promoting bacteria (PGPB), Bacillus subtilis strain CV21, and investigated its antifungal and plant growth-promoting properties. The bacterium produced cell wall-degrading enzymes such as chitinase, β-1,3-glucanase, and protease and effectively antagonized both A. alternata CH3 and A. alternata CH10 and the crude enzyme fraction (100 µl/mL) of B. subtilis CV21 inhibited spore germination by 40.1 % and 25.1 % and reduced mycelial growth by 29.1 % and 42.5 % against A. alternata CH3 and A. alternata CH10. The crude enzyme fraction degraded the cell walls of both phytopathogens in a concentration-dependent manner, causing swelling with bulbous structures in the hyphal cell, and cell wall lysis with severe perforations, loss of shape and aggregation of spores compared to control. Treatment with the bacterial culture broth on flowering cherry seedlings reduced CLS disease by 1.3-fold and 3.4-fold compared to the chemical treatment and the control group, respectively. In addition, B. subtilis CV21 also demonstrated plant growth-promoting properties such as indole-3-acetic acid (IAA) production up to a maximum concentration of 3.5 µg/mL during the experimental period and exhibited potential for phosphate solubilization and nitrogen fixation. The inoculation of nursery seedlings with B. subtilis CV21 culture broth improved the chlorophyll content, and increased seedling growth and biomass production compared to chemical treatment and the control group. The results demonstrate that the B. subtilis CV21 could be effectively applied as a bio-fungicide to control CLS and as bio-stimulant/bio-fertilizer to enhance the growth of flowering cherry seedlings.

BackgroundIn September 2022, Uganda experienced an outbreak of Sudan virus disease (SVD), mainly in central Uganda. As a result of enhanced surveillance activities for Ebola disease, samples from several patients with suspected viral hemorrhagic fever (VHF) were sent to the VHF Program at Uganda Virus Research Institute (UVRI), Entebbe, Uganda, and identified with infections caused by other viral etiologies. Herein, we report the epidemiologic and laboratory findings of Crimean-Congo hemorrhagic fever (CCHF) cases that were detected during the SVD outbreak response.MethodologyWhole blood samples from VHF suspected cases were tested for Sudan virus (SUDV) by real-time reverse transcription-polymerase chain reaction (RT-PCR); and if negative, were tested for CCHF virus (CCHFV) by RT-PCR. CCHFV genomic sequences generated by metagenomic next generation sequencing were analyzed to ascertain strain relationships.Principal findingsBetween September 2022 and January 2023, a total of 2,626 samples were submitted for VHF testing at UVRI. Overall, 13 CCHF cases (including 7 deaths; case fatality rate of 53.8%), aged 4 to 60 years, were identified from 10 districts, including several districts affected by the SVD outbreak. Four cases were identified within the Ebola Treatment Unit (ETU) at Mubende Hospital. Most CCHF cases were males engaged in livestock farming or had exposure to wildlife (n = 8; 61.5%). Among confirmed cases, the most common clinical symptoms were hemorrhage (n = 12; 92.3%), fever (n = 11; 84.6%), anorexia (n = 10; 76.9%), fatigue (n = 9; 69.2%), abdominal pain (n = 9; 69.2%) and vomiting (n = 9; 69.2%). Sequencing analysis showed that the majority of identified CCHFV strains belonged to the Africa II clade previously identified in Uganda. Two samples, however, were identified with greater similarity to a CCHFV strain that was last reported in Uganda in 1958, suggesting possible reemergence.Conclusions/significanceIdentifying CCHFV from individuals initially suspected to be infected with SUDV emphasizes the need for comprehensive VHF testing during filovirus outbreak responses in VHF endemic countries. Without expanded testing, CCHFV-infected patients would have posed a risk to health care workers and others while receiving treatment after a negative filovirus diagnosis, thereby complicating response dynamics. Additionally, CCHFV-infected cases could acquire an Ebola infection while in the ETU, and upon release because of a negative Ebola virus result, have the potential to spread these infections in the community.

1. Biodiversity is an important component of natural ecosystems, with higher species richness often correlating with an increase in ecosystem productivity. Yet, this relationship varies substantially across environments, typically becoming less pronounced at high levels of species richness. However, species richness alone cannot reflect all important properties of a community, including community evenness, which may mediate the relationship between biodiversity and productivity. If the evenness of a community correlates negatively with richness across forests globally, then a greater number of species may not always increase overall diversity and productivity of the system. Theoretical work and local empirical studies have shown that the effect of evenness on ecosystem functioning may be especially strong at high richness levels, yet the consistency of this remains untested at a global scale. 2. Here, we used a dataset of forests from across the globe, which includes composition, biomass accumulation and net primary productivity, to explore whether productivity correlates with community evenness and richness in a way that evenness appears to buffer the effect of richness. Specifically, we evaluated whether low levels of evenness in speciose communities correlate with the attenuation of the richness–productivity relationship. 3. We found that tree species richness and evenness are negatively correlated across forests globally, with highly speciose forests typically comprising a few dominant and many rare species. Furthermore, we found that the correlation between diversity and productivity changes with evenness: at low richness, uneven communities are more productive, while at high richness, even communities are more productive. 4. Synthesis. Collectively, these results demonstrate that evenness is an integral component of the relationship between biodiversity and productivity, and that the attenuating effect of richness on forest productivity might be partly explained by low evenness in speciose communities. Productivity generally increases with species richness, until reduced evenness limits the overall increases in community diversity. Our research suggests that evenness is a fundamental component of biodiversity–ecosystem function relationships, and is of critical importance for guiding conservation and sustainable ecosystem management decisions.

# Background Given rising youth sport participation, 8 to 10-year-olds increasingly display comparable lower-extremity injury incidence to 11 to 17-year-olds and require effective return to sport criteria. One such criterion which quantifies dynamic stability is the Y-Balance Test (YBT), though it has not been validated in children under age 11. # Hypothesis/Purpose The purpose of this study was to examine the performance of 8 to 10-year-old patients on the YBT after lower-extremity injury and determine how these results compare to larger samples of age-grouped athletes within the validated 11 to 17-year-old range. It was hypothesized that 8 to 10-year-olds would display different normalized YBT distances compared to 11 to 17-year-olds. # Study Design Cross-sectional Study. # Methods Patients (N=1093) aged 8 to 17 who presented to a pediatric sports medicine practice with a lower-extremity injury and completed the YBT between December 2015-May 2021 were included. Anterior, posteromedial, and posterolateral YBT scores were collected at return-to-sport for affected and unaffected limbs. Scores were normalized to limb length, and composite scores were created. Between-limb differences were calculated in groups of ages 8-10, 11-12, 13-14, and 15-17. Groups were also evaluated for differences by sex. # Results A rise in performance was observed in unaffected limb anterior reach from ages 8 to 10 years to 11 to 12 years followed by a subsequent significant decrease at older ages (p

Thyroid eye disease (TED) remains challenging for clinicians to evaluate and manage. Novel therapies have recently emerged, and their specific roles are still being determined. Most patients with TED develop eye manifestations while being treated for hyperthyroidism and under the care of endocrinologists. Endocrinologists, therefore, have a key role in diagnosis, initial management, and selection of patients who require referral to specialist care. Given that the need for guidance to endocrinologists charged with meeting the needs of patients with TED transcends national borders, and to maximize an international exchange of knowledge and practices, the American Thyroid Association and European Thyroid Association joined forces to produce this consensus statement.

Purpose: To define the surgical anatomy of the meniscotibial ligament complex of the pediatric medial and lateral menisci and their relation to the proximal tibial physis and posterior joint capsule. Methods: Fourteen pediatric cadaveric knee specimens (aged 3 months to 11 years) were dissected to clarify the relation of the posterior knee capsule, the meniscus, and the meniscotibial ligament complex. Metallic markers were placed marking the meniscotibial ligament capsular attachment on the proximal tibia. Specimens underwent computed tomography scanning to evaluate pin placement and relation to the physis. A digital measurement tool was used to measure the distances between the proximal tibial physis and the pins (placed at 5 points on both the lateral and medial menisci). Results: In each specimen, clear separation was noted between the posterior joint capsule from the meniscus and meniscotibial ligament complex in the medial and lateral compartments. There was an increase in the distance between the proximal tibial physis and the insertion points of the meniscotibial ligament complex with increasing specimen age. For both the medical and lateral menisci in group 1, the median meniscotibial ligament insertion points were often less than 7 mm (interquartile range, 0.00-7.8 mm) away from the physis. The median meniscotibial ligament insertion points in group 2 tended to be farther from the physis but always less than 20 mm (interquartile range, 2.5-17.5 mm)—and as close as less than 5 mm (lateral posterior root). Conclusions: In this anatomic study of pediatric knees, we observed a distinct recess/cul-de-sac space between the posterior knee capsule and meniscal attachments in all specimens. This defines a distinct plane between the posterior knee capsule and the meniscotibial ligament complex, with a distance between the physis and meniscotibial ligament capsular attachments that increases with age. Clinical Relevance: The anatomic parameters evaluated in our study should be considered as future meniscal repair and transplantation techniques aim to restore the meniscal anatomy, stability, and mobility provided by the meniscotibial ligament complex and capsule structures.

The history and physical exam are crucial components of the initial assessment of hip pain in adolescents and young adults to identify the cause of the pain, distinguish between common causes of early degeneration such as femoroacetabular impingement (FAI) and acetabular dysplasia (instability), and guide further workup and management. Different aspects of the history and exam are specific to various common causes of hip pain in this patient population. The purpose of this review is to synthesize these components to provide a comprehensive approach to the history and physical exam for adolescents and young adults presenting with hip pain. Key Concepts: (1) Common signs that suggest a mechanical hip problem, but are not specific for the etiology, include symptoms that worsen with activity, discomfort in a seated position, pain on rising from a seated position, or difficulty with ascending or descending stairs. (2) A Trendelenburg gait is caused by insufficient abductors that are unable to maintain a level pelvis and is commonly associated with hip instability due to the biomechanical disadvantage of the dysplastic hip joint. (3) Obligate external rotation of the hip during hip flexion is concerning for slipped capital femoral epiphysis (SCFE) and warrants an AP pelvis and frog leg lateral view for evaluation. (4) The Prone Apprehension Relocation Test (PART) assesses for anterior undercoverage of the acetabulum, and a positive test has been found to be correlated with radiographic markers of instability.

ABSTRACT: Radiographic evaluation of hip pain in adolescents and young adults is an important component of the assessment to aid in the identification of the cause of pain, distinguish between etiologies of early hip degeneration such as acetabular dysplasia (instability) and femoroacetabular impingement, and guide further workup and management. Recent advances in radiographic assessment include the importance of obtaining a standing anterior-posterior radiograph to illustrate the functional position of the pelvis, the use of anterior and posterior wall indices to illustrate anterior and posterior wall coverage and the importance of interpreting radiographic measures in the context of a patient’s sagittal balance. Advances in magnetic resonance imaging, computed tomography, and ultrasound have also occurred and can provide further diagnostic clarity. The purpose of this work is to review the literature to provide a systematic approach to the radiographic evaluation of hip pain in skeletally mature adolescents and young adults. Key Concepts: (1) The standing AP pelvis, 45° Dunn, and false-profile views provide a preliminary comprehensive radiographic assessment of the symptomatic hip in the skeletally mature adolescent and young adult and help to distinguish between instability and impingement. (2) The Lateral Center Edge Angle (LCEA) should be augmented by the anterior center edge angle (ACEA), anterior wall index (AWI), and posterior wall index (PWI) to obtain a more complete understanding of 3-dimensional femoral head coverage from plain radiographs. (3) While the crossover and posterior wall signs on radiographs can be helpful in screening for acetabular retroversion and anteversion, CT should be used to confirm if considering reorientation or resection. (4) Cam morphology should be quantitatively assessed using the alpha angle and head-neck offset on the 45° Dunn view. (5) Dynamic ultrasound may be useful in illustrating the motion associated with impingement and instability in real-time but may be limited by the technician-dependent nature of this modality.