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Soil microorganisms play crucial roles in improving nutrient cycling, maintaining soil fertility in desert ecosystems such as the West Ordos desert ecosystem in Northern China, which is home to a variety of endangered plants. However, the relationship between the plants–microorganisms–soil in the West Ordos desert ecosystem is still unclear. Tetraena mongolica, an endangered and dominant plant species in West Ordos, was selected as the research object in the present study. Results showed that (1) there were ten plant species in the Tetraena mongolica community, belonging to seven families and nine genera, respectively. The soil was strongly alkaline (pH = 9.22 ± 0.12) and the soil nutrients were relatively poor; (2) fungal diversity was more closely related to shrub diversity than bacterial and archaeal diversity; (3) among the fungal functional groups, endomycorrhizal led to a significant negative correlation between shrub diversity and fungal diversity, because endomycorrhizal had a significant positive effect on the dominance of T. mongolica, but had no significant effect on other shrubs; (4) plant diversity had a significant positive correlation with the soil inorganic carbon (SIC), total carbon (TC), available phosphorus (AVP) and available potassium (AVK). This study revealed the effects of soil properties and soil microorganisms on the community structure and the growth of T. mongolica and provided a theoretical basis for the conservation of T. mongolica and the maintenance of biodiversity in desert ecosystems. [ABSTRACT FROM AUTHOR]

Soil microbes play crucial roles in grassland ecosystem functions, such as soil carbon (C) pool and nutrient cycle. Soil microbes in grasslands are susceptible to the degradation mediated by climate change and anthropogenic disturbance. However, research on how the degradation influences the diversity and community structure of different soil microbial taxa is relatively scarce. We conducted a large-scale field survey to describe the effects of four degradation levels (PD: potential degradation, LD: light degradation, MD: moderate degradation, and SD: severe degradation) on soil bacterial and fungal community in the semi-arid grasslands of northern China. We found that soil moisture, nutrients, and clay content decreased, but soil sand content increased along the increasing degradation gradient. However, the degradation had no effects on soil pH and the C:N ratio. Grassland degradation had non-significant effect on soil bacterial diversity, but it significantly affected soil bacterial community structure. The degradation decreased soil fungal diversity and had a relatively larger influence on the community structure of soil fungi than that of bacteria. The community composition and structure of soil fungi were mainly affected by soil nutrients and texture, while those of soil bacteria were mainly affected by soil pH. These results indicate that changes in soil properties induced by grassland degradation mainly drive the variation in the soil fungal community and have less effect on the soil bacterial community. This study reveals the sensitivity of soil fungal community to grassland degradation, highlighting the priority of soil fungal community for the management and restoration of degraded grasslands. [ABSTRACT FROM AUTHOR]

Aim: The interactions between plants and soil microbes play crucial roles in modulating the function and stability of terrestrial ecosystems. However, the relationships between plant and soil microbial diversity for different taxa have remained been elusive. Location: Northern China. Major taxa: Plant and soil microbes of grassland ecosystems. Time period: 2018 and 2019. Methods: We conducted a transect survey across grasslands to measure plant diversity, plant traits, and soil microbial diversity. High throughput sequencing was used to assess soil microbial diversity for bacterial 16S ribosomal RNA (16S) and fungal internal transcribed spacer (ITS) regions on an Illumina MiSeq. The random forest algorithm was used to determine the important spatial and environmental variables in predicting plant and microbial diversity, and structural equation modelling was used to examine the direct and indirect effects of climatic and edaphic variables on plant and microbial diversity. Results: Plant diversity was positively correlated with the diversity of soil fungi, particularly for predicted arbuscular mycorrhizal fungi (AMF) and saprotrophic fungi, and they were positively related to soil nutrients and texture. However, the correlation between plant and bacterial diversity varied by phyla and functional guilds, resulting in decoupling between plant and soil bacterial diversity. Community weighted mean leaf C:N ratio indirectly decreased soil fungal diversity through a negative relationship with soil total nitrogen. Soil bacterial and fungal diversity increased with increasing functional richness of specific leaf area and stem density, respectively. Main conclusions: These findings have contributed to unravelling the direct and indirect linkages between plant and soil fungal diversity, highlighting particularly strong linkages between plant diversity and predicted AMF and saprotrophic fungi diversity. However, we failed to detect an overall linkage between plant and soil bacterial diversity. Still, our findings suggest that integrating soil fungi into the framework of plant diversity conservation is conducive to biodiversity restoration in degraded grassland ecosystems. [ABSTRACT FROM AUTHOR]

Large herbivores and insects commonly coexist and play important functional roles in grassland ecosystems. The interactive effects of these two animal groups in shaping ecosystem processes and functioning are poorly understood. In a semi‐arid grassland of northeastern China, we previously found a reciprocal facilitation between large herbivores (cattle; Bos tarurs) and ants: cattle grazing led to a twofold increase in ant mound abundance compared with ungrazed sites, while the presence of ant mounds, in turn, increased the foraging of cattle during the peak of the growing season.Here, by using a large‐scale, 4‐year (2010–2013) manipulative experiment, we further investigated how such a facilitation between large herbivores and ants can affect a key ecosystem process, litter decomposition. Using a set of small‐scale reciprocal translocation litterbag experiments, we separated the effects of litter quality and soil microenvironmental factors altered by cattle and ants on litter decomposition rates.A significant interaction between the experimental factors, cattle grazing and ant presence, showed that litter decomposition rate was at the highest levels when both cattle and ants were present, with only a small impact when each was present on its own. Mechanistically, cattle and ants exerted limited effects on litter quality (litter C:N ratio). However, these animals greatly altered soil microenvironments by increasing soil N availability, which in turn increased soil microbial biomass and accelerated decomposition process.Synthesis. Our results demonstrate how positive interactions between two groups of animals, large herbivores and ants, can affect decomposition rates, with important consequences for ecosystem carbon and nutrient cycling. Large herbivores, either domestic or wild, often coexist and interact frequently with a diverse of other fauna in terrestrial ecosystems. Assessing their interactive effects will help us to better understand their role in shaping ecosystem processes and functioning with important management implications. A free Plain Language Summary can be found within the Supporting Information of this article. [ABSTRACT FROM AUTHOR]

Objective: The personality of military personnel is an important factor for their mental health. It has been revealed that military personnel's mental health has changed over the past decades. The objective of the present study was to examine the birth cohort changes in the personality of Chinese military personnel. Methods: To examine the birth cohort changes in the personality of Chinese military personnel, a cross‐temporal meta‐analysis of 53 studies that measured the personality of Chinese military personnel with the Eysenck Personality Questionnaire from 1991 to 2017 was conducted (61 data points, N = 55 708). Results: The results showed that during this period, the respondents' personality traits changed significantly. Specifically, their levels of neuroticism and psychoticism decreased by 0.84 and 0.62 standard deviations respectively, and the younger participants exhibited higher levels of extraversion. Conclusions: This study found that Chinese military personnel showed decreasing neuroticism and psychoticism from 1991 to 2017 and that younger participants exhibited higher levels of extraversion. © 2020 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Sand burial and precipitation drive plant community structure and functions in semiarid desertified areas, while net primary productivity (NPP) is one of the most important indicators of plant community function. However, how NPP responds to sand burial in combination with changed precipitation regimes is still unclear. We conducted a field experiment with simultaneous sand burial and enhanced precipitation treatments to test the responses of both aboveground net primary productivity (ANPP) and belowground net primary productivity (BNPP) in a semiarid desertified steppe in North China. The results showed that sand burial significantly affected the community ANPP but had no significant effects on the community BNPP. Sand burial increased the ANPP of rhizome grass and decreased the ANPP of perennial herbs, bunchgrass and annual herbs, with no significant effects on legume herbs, while enhanced precipitation did not significantly affect the community ANPP and BNPP or the ANPP of all five plant functional types (PFTs). Sand burial combined with enhanced precipitation mediated the vertical allocation of BNPP in the community. There are multiple significant relationships between the ANPP of different PFTs and the BNPP among the different soil layers. These findings will be conducive to understanding the consequences of grassland desertification under the background of climate change, with corresponding implications for grassland management and vegetation restoration in semiarid desertified areas. [ABSTRACT FROM AUTHOR]

According to the happiness-income paradox, economic growth within a country does not necessarily lead to an increase in well-being. However, previous literature also showed that economic growth has a greater impact on well-being in a low-income country than a high-income country. China is a typical developing country that has experienced dramatic development in recent decades. How did the well-being of the Chinese change? To examine birth cohort changes in Chinese college students' subjective well-being, a cross-temporal meta-analysis that involved 100 studies was conducted (106 data points, N = 55,830). The results showed that Chinese college students' well-being increased by at least 0.45 standard deviations from 2002 to 2017. In addition, their subjective well-being was significantly correlated with social indicators (e.g., GDP per capita, divorce rate, and university enrollment rate) for the corresponding years and 3 years prior to the collection of subjective well-being data. It is evident that social changes play an important role in predicting changes in well-being. [ABSTRACT FROM AUTHOR]

Using samples from eastern China (c. 25 – 41° N and 99 – 123° E) and from a common garden experiment, we investigate how Mg concentration varies with climate across multiple trophic levels. In soils, plant tissue (Oriental oak leaves and acorns), and a specialist acorn predator (the weevil Curculio davidi), Mg concentration increased significantly with different slopes from south to north, and generally decreased with both mean annual temperature (MAT) and precipitation (MAP). In addition, soil, leaf, acorn and weevil Mg showed different strengths of association and sensitivity with climatic factors, suggesting that distinct mechanisms may drive patterns of Mg variation at different trophic levels. Our findings provide a first step toward determining whether anticipated changes in temperature and precipitation due to climate change will have important consequences for the bioavailability and distribution of Mg in food chain. [ABSTRACT FROM AUTHOR]

Aims Our aim was to study how diversity and dominance of plant species and plant functional types (PFTs) change and covary across three dune fixation stages in the Chinese steppe zone. Methods In the Chinese steppe zone, we measured coverage, mean height and density of each plant species in three types of dunes (mobile, semi-fixed and fixed dunes) in four sites (Mu Us, Otindag, Hulunbeir and Horqin). Plant species were grouped into 24 PFTs according to their lifespan, photosynthetic pathway, reproductive mode and life form. Dominance of each plant species and PFT were determined, and species diversity and PFT diversity were quantified using Shannon–Wiener index. Important Findings PFT diversity was positively related to plant species diversity in each dune stage, but PFT diversity increased more with increasing plant species diversity in the mobile and semi-fixed dunes than in the fixed dunes. Dune fixation stage explained 87.2% of the variation in plant species diversity and 84.8% of the variation in PFT diversity. Dominant species and PFTs differed among the three dune fixation stages; the more fixed the dunes were, the more perennial, shrubby, clonal and C3 species co-dominated. Specifically, in mobile dunes annual C4 non-clonal herbs were the most dominant, and in semi-fixed and fixed dunes perennial C3 clonal shrubs were most dominant. [ABSTRACT FROM PUBLISHER]

Variation in plant functional traits is the product of evolutionary and environmental drivers operating at different scales. Little is known about whether, or how, this variation is coordinated between aboveground and belowground organs across and within spatial scales., We address these questions using a hierarchically designed dataset of pairwise leaf and root traits related to carbon and nutrient economy of 64 species belonging to 14 plant communities in northern Chinese semi-arid and arid regions., While both root and leaf traits showed most of their variance among (individuals and) species within communities, leaf trait variance tended to be relatively higher at coarser spatial scales than root trait variance. While leaf nitrogen (N) per area to root N per length ratio increased and specific leaf area to specific root length and leaf [N] to root [N] ratios decreased from semi-arid to arid environments owing to climatic/edaphic shifts, the matching pairs showed a strong pattern of positive correlation that was upheld across spatial scales and geographic areas., Thus, trade-offs in plant resource investment across organs within individual vascular plants are constrained within a rather narrow range of variation. A new challenge will be to test whether and how such trait coordination is also seen within and across other biomes of the world. [ABSTRACT FROM AUTHOR]

Solar radiation mediated photodegradation of leaf litter has been studied substantially as it plays important roles in the cycling of carbon (C) and nutrients in dryland ecosystems. However, the mechanism by which ultraviolet (UV) radiation and its interaction with litter quality and microbial degradation affect dryland litter decomposition is still uncertain. A field experiment was carried out in semiarid Mu Us inland dunes of Inner Mongolia, China to investigate the effects of UV radiation and litter position on leaf litter decomposition of eight contrasting species (three perennial grasses, three shrubs, two annual forbs) representing different litter qualities over a whole year of incubation. The results showed that UV radiation increased mass loss of suspended litters for two perennial grasses and two annual forbs, but had no significant effect on the other four species considered; across species the percentage increase in mass loss ranged from 4.5 to 27.3% with an average of 13.7%. C release from suspended litters in response to UV radiation showed similar patterns with mass loss. Nitrogen (N) release from litters on the soil surface was lower than in suspended position because the former was involved in N immobilization driven by microbial decomposition. There were no net effects of UV radiation on decomposition rates of surface litters possibly due to the positive effects of photochemical process offsetting negative effects on microbes. Multiple linear regressions showed that the C:N ratio of initial leaf litter and leaf dry matter content (LDMC) could predict the rate of litter decomposition, in which litter C:N ratio had stronger influence. The findings, based on multiple species, highlight the importance of photodegradation on litter nitrogen and/or carbon mineralization in drylands as mediated by different abiotic and biotic drivers. [ABSTRACT FROM AUTHOR]

• Temperate grasslands substantially immobilized non-growing-season-deposited N. • Soils and microbes were the initial main sinks for the deposited N. • Plants were the main sink for the deposited N over the long term. • Non-growing-season N input had little impact on potential ecosystem N sequestration. • Grazing prohibition increased N retention ecosystem-wide. In N-limited temperate regions, atmospheric N deposition remains high over the non-growing season. However, the retention dynamics of non-growing season N input within the ecosystem remain unclear. Using an isotopic approach, we investigated the initial retention and subsequent dynamics of 15N (1.5 g 15N m−2) in the soils, microbes, plants, and litter over three years in grazing-prohibited (PG) and heavily grazed treatments (HG) in northern China. For initial retention (21 days after 15N addition), most 15N was immobilized in soils and microbes, while less was taken up by plants. Soil and microbial 15N immobilization were significantly higher when grazing was prohibited, although plant 15N acquisition was not affected by grazing. After initial retention, rapid 15N loss was observed in microbes and soils, while 15N levels were sustained longer in plants and litter. The 15N residence times were longer when grazing was prohibited. The 15N acquisition capacity varies among plant taxa: perennial grasses and forbs accumulated 15N rapidly, while sagebrush and legumes acted slowly. Although the added 15N had significant contribution to early spring N demands of soil microbes and plants, it did not increase microbial or plant biomass N. Our results showed that non-growing season exogenous N was primarily retained by soil biota in temperate grasslands in the early stage, but N retention is finally sustained in soil and plants. The findings highlighted the importance of soil microbes in sustaining N upon N input, inferring the needs for considering the microbial role for better understanding N cycling in the temperate grasslands. [ABSTRACT FROM AUTHOR]

• Aridity as a dominant filtering factor affected soil microbial network structure. • Increasing aridity reduced the complexity and stability of soil microbial networks. • Soil heterogeneity enhanced soil microbial network complexity and stability. Soil microbes play vital roles in mediating the functions and services of terrestrial ecosystems in the context of ongoing climate change and human disturbance. There are complex interactions between soil microbial taxa. However, research on the drivers of soil microbial network complexity and stability based on microbial taxa interactions is still in its infancy. We examined network structure and the complexity and stability of soil microbial communities across a large-scale environmental gradient in semi-arid grasslands of northern China by combining network theory and high-throughput sequencing. We found that aridity was the strongest driver of soil microbial network structure. Increasing aridity directly reduced the complexity and stability of soil microbial networks by decreasing the ratio of microbial taxa that participated in network construction and the ratio of potential positive and negative interactions of networks. Soil heterogeneity enhanced microbial network complexity and stability by potentially promoting diverse host plants and mediating uneven distribution of soil resources. These findings suggest that aridity and decreasing soil heterogeneity may have detrimental influences on soil microbial functions and the associated plant performance. This study provides new insights into the controls of climatic and/or edaphic variables in regulating soil microbial networks and highlights the importance of environmental heterogeneity in community assembly mechanisms of soil microbes. [ABSTRACT FROM AUTHOR]

Background and Aims: Seed heteromorphism is a plant strategy that an individual plant produces two or more distinct types of diaspores, which have diverse morphology, dispersal ability, ecological functions and different effects on plant life history traits. The aim of this study was to test the effects of seasonal soil salinity and burial depth on the dynamics of dormancy/germination and persistence/depletion of buried trimorphic diaspores of a desert annual halophyte Atriplex centralasiatica., Methods: We investigated the effects of salinity and seasonal fluctuations of temperature on germination, recovery of germination and mortality of types A, B, C diaspores of A. centralasiatica in the laboratory and buried diaspores in situ at four soil salinities and three depths. Diaspores were collected monthly from the seedbank from December 2016 to November 2018, and the number of viable diaspores remaining (not depleted) and their germinability were determined., Results: Non-dormant type A diaspores were depleted in the low salinity "window" in the first year. Dormant diaspore types B and C germinated to high percentages at 0.3 and 0.1 mol L -1 soil salinity, respectively. High salinity and shallow burial delayed depletion of diaspore types B and C. High salinity delayed depletion time of the three diaspore types and delayed dormancy release of types B and C diaspores from autumn to spring. Soil salinity modified the response of diaspores in the seedbank by delaying seed dormancy release in autum and winter and by providing a low-salt concentration window for germination of non-dormant diaspores in spring and early summer., Conclusions: Buried trimorphic diaspores of annual desert halophyte A. centralasiatica exhibited diverse dormancy/germination behavior in respond to seasonal soil salinity fluctuation. Prolonging persistence of the seedbank and delaying depletion of diaspores under salt stress in situ primarily is due to inhibition of dormancy-break. The differences in dormancy/germination and seed persistence in the soil seedbank may be a bet-hadging strategy adapted to stressful temporal and spatial heterogeneity, and allows A. centralasiatica to persist in the unpredictable cold desert enevironment., (© 2024. The Author(s).)

Ecosystem functioning plays a crucial role in maintaining human welfare. Terrestrial ecosystems provide multiple ecosystem services simultaneously, such as carbon sequestration, nutrient cycling, water purification, and biodiversity conservation, known as ecosystem multifunctionality (EMF). However, the mechanisms by which biotic and abiotic factors, and their interactions regulate EMF in grasslands are unclear. We conducted a transect survey to illustrate the single and combined effects of biotic factors (including plant species diversity, trait-based functional diversity, community-weighted mean (CWM) of traits, and soil microbial diversity) and abiotic factors (including climate and soil) on EMF. Eight functions were investigated, including aboveground living biomass and litter biomass, soil bacterial biomass, fungal biomass, arbuscular mycorrhizal fungi biomass, and soil organic carbon storage, total carbon storage and total nitrogen storage. We detected a significant interactive effect between plant species diversity and soil microbial diversity on the EMF; Structural equation model showed that soil microbial diversity indirectly affected EMF by regulating plant species diversity. These findings highlight the importance of the interaction effect of above- and below-ground diversity on EMF. Both plant species diversity and functional diversity had similar explanatory power for the variation in EMF, implying that niche differentiation and multifunctional complementarity among plant species and traits are essential in regulating the EMF. Furthermore, the effects of abiotic factors on EMF were stronger than those of biotic factors via direct and indirect pathways affecting above- and below-ground biodiversity. As a dominant regulator, the soil sand content was negatively correlated with EMF. These findings indicate the vital role of abiotic mechanisms in affecting EMF, and deepen our understanding of the single and combined effects of biotic and abiotic factors on EMF. We conclude that soil texture and plant diversity, representing crucial abiotic and biotic factors, respectively, are important determinants of the EMF of grasslands., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

Background: The effectiveness of postoperative adjuvant transarterial chemoembolization (TACE) on survival and recurrence in tumor-node-metastasis (TNM) stage I intrahepatic cholangiocarcinoma (ICC) after radical resection remains unclear. This study aimed to compare overall survival (OS) and recurrence-free survival (RFS) in TNM stage I ICC patients with and without postoperative TACE., Methods: A retrospective cohort study was conducted on TNM stage I ICC patients who had undergone R0 resections with curative intent in Shanghai Eastern Hepatobiliary Surgery Hospital from January 2012 to December 2016. A total of 269 patients were divided into two groups: (I) 35 patients who received postoperative TACE and (II) 234 patients no TACE. Staging was performed according to the 8th edition of American Joint Committee on Cancer (AJCC) TNM staging system. The tumor-related RFS and OS were estimated by the Kaplan-Meier method. Cox proportional regression model was employed to evaluate the prognosis between the two groups., Results: In all patients, the median OS was 66.8 months. After R0 resection, adjuvant TACE could not improve the survival of TNM stage I patients, and the OS of the TACE group was not better than that of the non-TACE group (P=0.7070). In addition, in the TACE group, the recurrence rate of TNM stage I ICC patients was statistically significantly higher than that of the non-TACE group (P=0.0328). Multivariable analysis revealed that adjuvant TACE was an independent predictor of worse RFS (HR: 1.88, 95% CI: 1.21-2.93)., Conclusions: Adjuvant TACE after radical surgery failed to prolong the OS and potentially delay recurrence for patients with TNM Stage I ICC. Adjuvant TACE might not be suitable for patients with TNM Stage I ICC.

Main Conclusion: Individuals of the annual halophyte Atriplex centralasiatica produce three kinds of diaspores that differ in dispersal, dormancy/germination response and type of seed bank formed, which likely is a bet-hedging strategy in the rainfall-unpredictable environment on the semi-arid, saline Ordos Plateau in Inner Mongolia, China. Seasonal fluctuations in environmental conditions provide germination cues for the establishment of seedlings at the right time and place to ensure plant survival and population regeneration. Diaspore heteromorphism is a phenomenon in which diaspores with stark qualitative differences in morphology and ecology are produced by the same maternal plant. Germination responses and dispersal times of the annual halophyte Atriplex centralasiatica were examined to determine the role of diaspore heteromorphism in its adaptation to salt desert conditions. A. centralasiatica is a tumbleweed that produces three types of diaspores that differ in morphology and ecophysiology. The relative potential dispersal ability and intensity of dormancy of the three diaspore types was type A (fan-shaped diaspores with yellow fruits) < type B (fan-shaped diaspores with black fruits) < type C (globular diaspores with black fruits). In the field, type A retained high germinability, but all of them were depleted from the (transient) soil seedbank in the first growing season. Types B and C cycled between dormancy and nondormancy, and 0 and > 90.0% remained in the soil seedbank 2 years after dispersal, respectively. The dormancy, dispersal and salt tolerance of type B diaspores were intermediate between those of A and C. Type A exhibited low dispersal-nondormancy, type B exhibited intermediate dispersal-intermediate dormancy and type C exhibited high dispersal ability-high dormancy. In the unpredictable salt desert habitat, the functional differences in germination and dispersal of the three diaspores act as a bet-hedging mechanism and ensure population establishment in different years by spreading germination over time and space.

Background and Aims: Long-term studies to disentangle the multiple, simultaneous effects of global change on community dynamics are a high research priority to forecast future distribution of diversity. Seldom are such multiple effects of global change studied across different ecosystems., Methods: Here we manipulated nitrogen deposition and rainfall at levels realistic for future environmental scenarios in three contrasting steppe types in Mongolia and followed community dynamics for 7 years., Key Results: Redundancy analyses showed that community composition varied significantly among years. Rainfall and nitrogen manipulations did have some significant effects, but these effects were dependent on the type of response and varied between ecosystems. Community compositions of desert and meadow steppes, but not that of typical steppe, responded significantly to rainfall addition. Only community composition of meadow steppe responded significantly to nitrogen deposition. Species richness in desert steppe responded significantly to rainfall addition, but the other two steppes did not. Typical steppe showed significant negative response of species richness to nitrogen deposition, but the other two steppes did not. There were significant interactions between year and nitrogen deposition in desert steppe and between year and rainfall addition in typical steppe, suggesting that the effect of the treatments depends on the particular year considered., Conclusions: Our multi-year experiment thus suggests that responses of community structure and diversity to global change drivers are ecosystem-dependent and that their responses to experimental treatments are dwarfed by the year-to-year community dynamics. Therefore, our results point to the importance of taking annual environmental variability into account for understanding and predicting the specific responses of different ecosystems to multiple global change drivers., (© The Author(s) 2019. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Sand burial is a common phenomenon in inland semi-arid and arid areas, affecting plant growth and even plant community structure. Precipitation regime, including the variation of precipitation intensity and frequency, also drives community structure and functions in such areas. However, few studies have focused on the combined effect of sand burial and changed precipitation regime on community function, specifically its role in carbon storage. A 2-yr field experiment with factorial treatments of precipitation (control, slight enhancement and strong enhancement) and sand addition (control and 5 cm sand addition) was conducted to test the responses of plant and soil carbon content in a semi-arid typical steppe in N China. Results showed that sand burial had no significant effect on plant carbon density, but significantly changed the allocation of plant carbon from aboveground to belowground; these responses differed among species and life forms in the community. Precipitation enhancement had no significant effects on plant carbon and its allocation, perhaps because effects of precipitation on plants are due more to precipitation frequency than to precipitation intensity per event. Sand burial and precipitation enhancement decreased soil carbon, especially soil organic carbon, and promoted soil carbon to be distributed deeper down the soil profile. These findings will help to understand how sand deposition affects plant and soil carbon storage and their allocation in plant communities under a changing precipitation regime, and more generally, to understand carbon storage dynamics in early-successional sandy ecosystems in the context of global change., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Background: This study examines the clinical utility of the level of increased platelet distribution width (PDW) as a predictor of outcome in patients with traumatic brain injury., Methods: In this retrospective study, 120 patients with traumatic brain injury (TBI) were recruited. Age, gender, PDW, and Glasgow Coma Scale (GCS) scores were measured. These patients were divided into two groups based on their 30-day outcomes. Receiver operating curves (ROCs) were generated to identify predictors of 30-day mortality., Results: One hundred twenty patients with traumatic brain injury were enrolled in this study, 89 males (74.2%) and 31 females (25.8%) with a median age of 49.5 (19 - 89) years. The in-hospital mortality rate was 10.8% (n = 13). PDW levels in non-surviving patients were higher than in surviving patients. The higher the PDW, the lower the GSC score. The area under the curve (AUC) for PDW levels with regard to predicting 30-day mortality was 0.88 (95% confidence interval (CI), 0.78 to 0.97; p < 0.001). There was correlation between PDW level and GCS score (r = -0.30, 95% confidence interval (CI), - 0.46 to - 0.13; p < 0.001)., Conclusions: PDW levels were associated with injury severity and mortality in patients with severe TBI.

Plant clonality, the ability of a plant species to reproduce itself vegetatively through ramets (shoot-root units), occurs in many plant species and is considered to be more frequent in cold or wet environments. However, a deeper understanding on the clonality-climate relationships along large geographic gradients is still scarce. In this study we revealed the clonality-climate relationships along latitudinal gradient of entire China spanning from tropics to temperate zones using clonality data for 4015 vascular plant species in 545 terrestrial communities. Structural equation modeling (SEM) showed that, in general, the preponderance of clonality increased along the latitudinal gradient towards cold, dry or very wet environments. However, the distribution of clonality in China was significantly but only weakly correlated with latitude and four climatic factors (mean annual temperature, temperature seasonality, mean annual precipitation, precipitation seasonality). Clonality of woody and herbaceous species had opposite responses to climatic variables. More precisely, woody clonality showed higher frequency in wet or climatically stable environments, while herbaceous clonality preferred cold, dry or climatically instable environments. Unexplained variation in clonality may be owed to the influences of other environmental conditions and to different clonal strategies and underlying traits adopted by different growth forms and phylogenetic lineages. Therefore, in-depth research in terms of more detailed clonal growth form, phylogeny and additional environmental variables are encouraged to further understand plant clonality response to climatic and/or edaphic conditions.