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SUMMARY: Ginger is cultivated in tropical and subtropical regions and is one of the most crucial spices worldwide owing to its special taste and scent. Here, we present a high‐quality genome assembly for 'Small Laiwu Ginger', a famous cultivated ginger in northern China. The ginger genome was phased into two haplotypes, haplotype A (1.55Gb), and haplotype B (1.44Gb). Analysis of Ty1/Copia and Ty3/Gypsy LTR retrotransposon families revealed that both have undergone multiple retrotransposon bursts about 0–1 million years ago. In addition to a recent whole‐genome duplication event, there has been a lineage‐specific expansion of genes involved in stilbenoid, diarylheptanoid, and gingerol biosynthesis, thereby enhancing 6‐gingerol biosynthesis. Furthermore, we focused on the biosynthesis of 6‐gingerol, the most important gingerol, and screened key transcription factors ZoMYB106 and ZobHLH148 that regulate 6‐gingerol synthesis by transcriptomic and metabolomic analysis in the ginger rhizome at four growth stages. The results of yeast one‐hybrid, electrophoretic mobility shift, and dual‐luciferase reporter gene assays showed that both ZoMYB106 and ZobHLH148 bind to the promoters of the key rate‐limiting enzyme genes ZoCCOMT1 and ZoCCOMT2 in the 6‐gingerol synthesis pathway and promote their transcriptional activities. The reference genome, transcriptome, and metabolome data pave the way for further research on the molecular mechanism underlying the biosynthesis of 6‐gingerol. Furthermore, it provides precious new resources for the study on the biology and molecular breeding of ginger. Significance Statement: We present a high‐quality genome assembly for 'Small Laiwu Ginger' with two haplotypes, haplotype A (1.55Gb) and haplotype B (1.44Gb). We find that ZoMYB106 and ZobHLH148 bind to the promoters of the key rate‐limiting enzyme genes ZoCCOMT1 and ZoCCOMT2 in the 6‐gingerol synthesis pathway and promote their transcriptional activities. [ABSTRACT FROM AUTHOR]

In the context that coal remains the main energy source of China now, the safety of coal mine production is still worth our attention. For the factors influencing the roof accident of coal mine roadway have great complexity and uncertainty, a new risk prediction method of coal mine roof accidents integrating T‐S fuzzy fault tree and Bayesian network (BN) is proposed. The constructed method determines the BN and the conditional probability tables according to the established T‐S fuzzy fault tree. The fault state and fuzzy fault rate of root nodes are described according to the fuzzy number. And the forward inference of Bayesian is used to calculate the probability of the accidents on the roadway roof based on the fault probability of the root nodes and actual fault probability during construction respectively, to realize the risk prediction of roof accidents. Finally, practical data are used to verify the new fusion risk evaluation method by taking two mines as cases. The results show that the influencing factors calculated by the new fusion risk prediction method are completely consistent with the actual situation, confirming the effectiveness and reliability of this method, which providing new ideas for the research about the risk prediction of coal mine roof accidents. [ABSTRACT FROM AUTHOR]

Aims/Introduction: To investigate the impact of visceral adipose tissue (VAT) on atherosclerosis in type 2 diabetes patients with normal bodyweight (OB[−]) in the Chinese population, and to further assess the sex–age differences between them. Materials and Methods: A total of 8,839 type 2 diabetes patients from two of the National Metabolic Management Centers in China were included in this study. Participants were classified into four groups by visceral fat area (VFA; cm2) and body mass index (BMI; kg/m2): VFA < 100 and BMI < 23.9 (VA[−]OB[−]), VFA < 100 and BMI ≥ 23.9 (VA[−]OB[+]), VFA ≥ 100 and BMI < 23.9 (VA[+]OB[−]), VFA ≥ 100 and BMI ≥ 23.9 (VA[+]OB[+]). Atherosclerosis was defined by brachial‐ankle pulse wave velocity (baPWV; cm/s), and we analyzed the association between VFA, BMI and the tertiles of baPWV values. Results: The VA(+)OB(−) prevalence was 3.7% among these participants. Patients with VA(+)OB(−) had the highest baPWV value (P < 0.001) and the highest proportion of the tertile 3 of baPWV (P < 0.001) among four groups, and were significantly associated with baPWV (standardized β = 0.026, P = 0.008). VFA was significantly related to tertile 2 to tertile 3 of baPWV in (OB[−]) type 2 diabetes patients, when compared with tertile 1 of baPWV, respectively. In sex–age stratified analysis, the association of VFA and the tertiles of baPWV showed sex differences. For the 55 years age stratification analysis, there was no age difference in the relationship between VFA and baPWV in (OB[−]) patients. Conclusion: Increased VAT was an independent risk factor for atherosclerosis in female type 2 diabetes patients with normal weight. [ABSTRACT FROM AUTHOR]

A deep extraterrestrial drilling mission potentially adds a new level of complexity, and it is crucial to understand the associated challenges. To cope with China's Chang'E 5 mission to return subsurface regolith samples from the Moon, a series of laboratory tests were performed to validate the lunar robotic drilling from 2015 to 2018. The tests took place in a simulated thermal‐vacuum regolith environment, a highly relevant lunar analog site. Force and temperature sensors were integrated into a 2‐m class dry auger coring drill to assess the mechanical and thermophysical status of the sampling process. The operation of the entire testing system was automated, covering regolith penetration and data collection and storage. The science team used sensing data to characterize the subsurface geologic strata, assess the conditions of the drilling robot, and direct the sampling strategy. This experiment represents an essential first step in understanding the technology and operational requirements for lunar drilling and sampling mission. Many laboratory tests have helped guide the design and implementation of the highly successful lunar regolith‐sampling task in the Chang'E 5 mission. This paper documents the experimental system design, highlighting some critical design criteria and design tradeoffs. It also discusses the results of laboratory testing and lists some of the key technological lessons learned. [ABSTRACT FROM AUTHOR]

Congeneric species may coexist at fine spatial scales through niche differentiation, however, the magnitude to which the effects of functional traits and phylogenetic relatedness contribute to their distribution along elevational gradients remains understudied. To test the hypothesis that trait and elevational range overlap can affect local speciesʼ coexistence, we first compared phylogenetic relatedness and trait (including morphological traits and leaf elements) divergence among closely related species of Rhododendron L. on Yulong Mountain, China. We then assessed relationships between the overlap of multiple functional traits and the degree of elevational range overlap among species pairs in a phylogenetic context. We found that phylogeny was a good predictor for most functional traits, where closely related species showed higher trait similarity and occupied different elevational niches at our study site. Species pairs of R. subgen. Hymenanthes (Blume) K. Koch showed low elevational range overlap and some species pairs of R. subgen. Rhododendron showed obvious niche differentiation. Trait divergence is greater for species in R. subgen. Rhododendron, and it plays an important role between species pairs with low elevational range overlap. Trait convergent selection takes place between co‐occurring closely related species that have high elevational range overlap, which share more functional trait space due to environmental filtering or ecological adaptation in more extreme habitats. Our results highlight the importance of evolutionary history and trait selection for species coexistence at fine ecological scales along environmental gradients. [ABSTRACT FROM AUTHOR]

Foundation species structure forest communities and ecosystems but are difficult to identify without long‐term observations or experiments. We used statistical criteria––outliers from size‐frequency distributions and scale‐dependent negative effects on alpha diversity and positive effects on beta diversity––to identify candidate foundation woody plant species in 12 large forest‐dynamics plots spanning 26 degrees of latitude in China. We used these data (1) to identify candidate foundation species in Chinese forests, (2) to test the hypothesis––based on observations of a midlatitude peak in functional trait diversity and high local species richness but few numerically dominant species in tropical forests––that foundation woody plant species are more frequent in temperate than tropical or boreal forests, and (3) to compare these results with data from the Americas to suggest candidate foundation genera in northern hemisphere forests. Using the most stringent criteria, only two species of Acer, the canopy tree Acer ukurunduense and the shrubby treelet Acer barbinerve, were identified in temperate plots as candidate foundation species. Using more relaxed criteria, we identified four times more candidate foundation species in temperate plots (including species of Acer, Pinus, Juglans, Padus, Tilia, Fraxinus, Prunus, Taxus, Ulmus, and Corlyus) than in (sub)tropical plots (the treelets or shrubs Aporosa yunnanensis, Ficus hispida, Brassaiopsis glomerulata, and Orophea laui). Species diversity of co‐occurring woody species was negatively associated with basal area of candidate foundation species more frequently at 5‐ and 10‐m spatial grains (scale) than at a 20‐m grain. Conversely, Bray‐Curtis dissimilarity was positively associated with basal area of candidate foundation species more frequently at 5‐m than at 10‐ or 20‐m grains. Both stringent and relaxed criteria supported the hypothesis that foundation species are more common in mid‐latitude temperate forests. Comparisons of candidate foundation species in Chinese and North American forests suggest that Acer be investigated further as a foundation tree genus. [ABSTRACT FROM AUTHOR]

Aims: It is widely accepted that deterministic and neutral dispersal processes are two of the principal mechanisms driving community assembly. However, the relative importance of these ecological drivers between distinct life stages both at community and individual species levels remains poorly understood in different vegetation types. Here, we address the following questions: (a) is there a ubiquitous process shaping tree assemblage; (b) how does the relative importance of environmental and dispersal processes vary through ontogeny in different vegetation types; and (c) will the spatial patterns of trees at community and individual species levels reflect similar contribution between ecological processes? Location: Yunnan province, southwest China. Methods: We used the Homogeneous Poisson, Homogeneous Thomas, Inhomogeneous Poisson, and Inhomogeneous Thomas point process models to predict the effect of stochastic, dispersal and/or environmental processes, respectively, on the distribution of trees across ontogeny in tropical, subtropical and subalpine forests. To evaluate the relative importance of models, we compared the observed and simulated patterns of the species–area relationship and the pair correlation function g(r) at community and species level, respectively. Results: The Homogeneous Thomas model was the model with the lowest Akaike information criterion (AIC) scores across ontogeny and forest types at community level. At the species level, however, Homogeneous Thomas, and Inhomogeneous Thomas predicted the distribution of large and small trees, respectively, with lower AIC values in two of our three plots. In the third plot, the Homogeneous Thomas model is dominant across ontogeny at the species level. Conclusions: Tree communities are assembled mainly by the dispersal process at community level. The relative importance of ecological processes for species distribution varies across life stages at the species level, suggesting that there is an ontogenetic shift of ecological processes in shaping tree distribution. Using different summary statistics at both community and species levels helps to discern the different spatial structures of species and increases our appreciation of the processes underpinning community assembly. [ABSTRACT FROM AUTHOR]

Aim: The mechanisms driving forest community assembly along elevational gradients remain elusive. The distinct strata in heterogeneous forest are subject to differing assembly mechanisms. This study aims to evaluate how different ecological mechanisms driving forest community assembly across strata and spatial scales, and to identify how these assemblages respond to different abiotic or biotic variables along an elevational gradient. Location: Yulong Mountain within Hengduan Mountains, Southwest China. Taxon: Seed plants. Methods: We sampled plant species along a 1,200 m elevational gradient across forest strata (trees, shrubs and herbs) at different spatial scales (neighbourhood and community). We integrated phylogenetic and functional diversity to disentangle the roles of ecological mechanisms in structuring community assembly. We also determined the relative effects of climatic, soil and biotic variables and their interactions on these community assemblages. Results: The phylogenetic and functional diversity of trees were lower at the extremes of the elevational gradient, where they were constrained by water availability or temperature. While communities with higher species diversity exhibited an overdispersed structure at mid‐elevations. For shrubs, overdispersion was exhibited at high elevations despite low species richness, which could be consistent with facilitative interactions or competition exclusion. However, most communities of herbs appear to have a markedly random structure, despite some incongruence between phylogenetic divergence and functional convergence, as well as influences from overstorey trees and local light conditions. The relative effects of abiotic variables on community structure were larger at the community scale than at the neighbourhood scale. Main conclusions: Our study emphasises the importance of considering phylogenies and traits in understanding the strata‐ and scale‐dependent mechanisms of forest community assembly. Collectively, results indicate that contrasting assembly mechanisms interact across different strata along elevational gradients to shape diverse forest communities. [ABSTRACT FROM AUTHOR]

Ecosystem light use efficiency (LUE) is a critical parameter in estimating CO2 uptake by vegetation from climatological and satellite data. However, the spatiotemporal dynamics and biophysical regulations of ecosystem‐level LUE are not well understood, resulting in large uncertainties in the estimation of gross primary productivity (GPP) using LUE‐based models. In this study, we used eddy covariance to explore spatiotemporal variations and controls of LUE in four contrasting forest ecosystems (savanna, tropical rainforest, subtropical evergreen forest, and subalpine coniferous forest). Based on 27 site years of data, we found that (1) the multiyear mean LUE was 0.063, 0.251, 0.247, and 0.140 g C· mol photon−1 in the four contrasting ecosystems, respectively; (2) the LUE in the wet season (May–October) was higher than that in the dry season in all studied ecosystems; (3) the leaf area index controlled GPP and LUE significantly and explained 74%, 29%, 54%, and 36% of the variation in GPP and 51%, 19%, 41%, and 54% of the variation in LUE in the four contrasting ecosystems, respectively; (4) path analysis revealed the critical roles of GPP and vapor pressure deficit in controlling LUE in these four forest ecosystems; and (5) under warming scenarios, LUE may decrease in savanna but increase in the other three ecosystems, while decreasing precipitation (P) may reduce LUE in the ecosystems studied. This study improves our understanding of the influence of biophysical factors on LUE and demonstrates how LUE changes with variations in temperature, soil moisture, and leaf area index, thereby improving estimations of large‐scale carbon exchange/cycling. Key Points: Evergreen broad‐leaved forest (EBF) ecosystem shows higher LUE than subalpine coniferous/savanna ecosystemsThe vapor pressure deficit (VPD) and leaf area index (LAI) largely determine the variability in LUEWarming might decrease LUE in the savanna ecosystem and may increase LUE in the other three ecosystems [ABSTRACT FROM AUTHOR]