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Based on the financing motivation of equity pledges, this study explores whether and how monetary policy adjustment affects the stock pledge behaviour of listed companies. The empirical findings show that monetary policy adjustments significantly affect the stock pledge of listed companies; that is, a tightening monetary policy increases the stock pledge phenomenon of listed companies, and an expansionary monetary policy reduces the stock pledge phenomenon. Heterogeneity analysis revealed that monetary policy had a greater impact on the stock pledges of non-state-owned enterprises, enterprises with weak government–enterprise relationships and enterprises without bank–enterprise relationship. The results of mechanism tests suggested that a quantitative monetary policy only affects the stock pledge behaviour of listed companies through financing costs and that a price-based monetary policy affects the stock pledge behaviour of listed companies through financing costs and financing scale. This article expands the literature on the impact of monetary policies on equity pledges and enriches studies on macroeconomic policies and microfirm behaviour.

Plants and soil bacteria exert a vital function in mediating soil ecosystem multifunctionality (EMF). Nevertheless, plant and soil bacteria interaction during forest secondary succession is poorly understood, and their roles in soil EMF remain largely unexplored. The dynamics of soil physicochemical properties and bacterial diversity was studied in southwest China during forest succession from coniferous to monsoon broadleaf evergreen. Interdomain ecological networks (IDEN) were adopted for investigating plant–bacteria associations. With the purpose of assessing how soil factors, bacterial community and plant diversity influenced soil EMF, the structural equation model (SEM) was used. It was discovered that both soil bacterial diversity and soil EMF gradually increased with the succession. IDEN analysis revealed that plant–bacteria ecological networks differed significantly across successional stages. Keystone plant species richness (KSR) increased with succession, which benefited soil bacteria diversity (path coefficient = 0.802, p < 0.001) while having a direct negative impact on pH (path coefficient = −0.602, p < 0.05) and C:N (path coefficient = −0.759, p < 0.001). Soil pH and C:N ratio declines were observed during forest secondary succession and were found to be inversely related to soil EMF. Furthermore, soil pH was found to be inversely related to bacterial diversity. The SEM analysis explained 88.2% of the variation in soil multifunctionality. The findings suggested that keystone plant species played a key function in regulating the variations of soil bacterial community and EMF (total effect = 0.813). Our study clarified the critical functions of keystone species in driving soil bacterial diversity and multifunctionality during forest succession and provided a new perspective on the relationship between above‐ and below‐ground. [ABSTRACT FROM AUTHOR]

Elastic interface states, which are usually generated at the interface of two connected domains with opposite topological invariant, have been successfully demonstrated in periodic structures. Therefore, the interface states determined by the position of interface between two domain walls in one-dimensional elastic systems are rarely reported, which were mainly restricted by the mirror-symmetric geometry of the unit cell. Jointing interface-dependent interface states were mostly implemented with analogs of quantum valley Hall effects in two-dimensional systems. Herein, we first observe two types of elastic interface states simultaneously occurred in one-dimensional combined metamaterials, where two interface modes separately located at two connected domain walls and they can be actively tuned simply through deforming two components on two sides. Flexible and versatile frequency shift and switch on–off characteristics of combination of two interface modes are demonstrated, which may be employed in the multifunctional elastic wave filters, tunable energy harvesting, and elastography devices. Our primitive cell of the soft metamaterial, which breaks the inversion symmetry along the horizontal direction, may be generalized to realize tunable elastic valley Hall edge states. [ABSTRACT FROM AUTHOR]

Plants live in association with a diversity of soil microorganisms, which are extremely important in affecting plant growth and soil biogeochemical cycling.By adopting plant trait‐based approaches, we explored the linkages between rhizosphere soil microbial activity and plant resource acquisition strategy of above‐ and below‐ground across a range of tree species in a subtropical evergreen mixed forest. The microbial activities were represented by diverse extracellular enzymes relevant to carbon, nitrogen and phosphorus cycling and soil organic carbon (SOC) mineralization.At the species level, leaf and root traits were mainly represented by two leading dimensions, that is, the 'fast‐slow' economics spectrum on which leaf and root traits were well aligned and the orthogonal collaboration gradient in the root.Both extracellular enzymes and SOC mineralization in the rhizosphere varied greatly across plant species. We found that diverse rhizosphere soil microbial activities positively correlated with the classical 'fast‐slow' conservation gradient of plant resource acquisition (especially above‐ground), that is, the rhizosphere soil microbes associated with fast‐growing plant species feature higher metabolism than that of slow‐growing plant species. In comparison, rhizosphere soil microbial activities were independent of the plant collaboration gradient in the root, and it might be an alternative exploitative strategy in foraging soil nutrients for plants.Synthesis. Our study strengthens the multivariate nature of plant resource acquisition in adapting to above‐ and below‐ground stresses. The findings on the linkages between rhizosphere soil microbial activity and plant resource acquisition strategy have the potential to improve our understanding and prediction of plant species turnover impacts on soil biogeochemical cycles. [ABSTRACT FROM AUTHOR]

Environment stress is a major threat to the existence of coral reefs and has generated a lot of interest in the coral research community. Under the environmental stress, corals can experience tissue loss and/or the breakdown of symbiosis between the cnidarian host and its symbiotic algae causing the coral tissue to appear white as the skeleton can be seen by transparency. Image analysis is a common method used to assess tissue response under the environmental stress. However, the traditional approach is limited by the dynamic nature of the coral-algae symbiosis. Here, we observed coral tissue response in the scleractinian coral, Montipora capricornis, using high frequency image analysis throughout the experiment, as opposed to the typical start/end point assessment method. Color analysis reveals that the process can be divided into five stages with two critical stages according to coral tissue morphology and color ratio. We further explore changes to the morphology of individual polyps by means of the Pearson correlation coefficient and recurrence plots, where the quasi-periodic and nonstationary dynamics can be identified. The recurrence quantification analysis also allows the comparison between the different polyps. Our research provides a detailed visual and mathematical analysis of coral tissue response to environmental stress, which potentially shows universal applicability. Moreover, our approach provides a robust quantitative advancement for improving our insight into a suite of biotic responses in the perspective of coral health evaluation and fate prediction. [ABSTRACT FROM AUTHOR]

Autumn phenology plays a key role in regulating the terrestrial carbon and water balance and their feedbacks to the climate. However, the mechanisms underlying autumn phenology are still poorly understood, especially in subtropical forests. In this study, we extracted the autumn photosynthetic transition dates (APTD) in subtropical China over the period 2003–2017 based on a global, fine‐resolution solar‐induced chlorophyll fluorescence (SIF) dataset (GOSIF) using four fitting methods, and then explored the temporal–spatial variations of APTD and its underlying mechanisms using partial correlation analysis and machine learning methods. We further predicted the APTD shifts under future climate warming conditions by applying process‐based and machine learning‐based models. We found that the APTD was significantly delayed, with an average rate of 7.7 days per decade, in subtropical China during 2003–2017. Both partial correlation analysis and machine learning methods revealed that soil moisture was the primary driver responsible for the APTD changes in southern subtropical monsoon evergreen forest (SEF) and middle subtropical evergreen forest (MEF), whereas solar radiation controlled the APTD variations in the northern evergreen‐broadleaf deciduous mixed forest (NMF). Combining the effects of temperature, soil moisture and radiation, we found a significantly delayed trend in APTD during the 2030–2100 period, but the trend amplitude (0.8 days per decade) was much weaker than that over 2003–2017. In addition, we found that machine learning methods outperformed process‐based models in projecting APTD. Our findings generate from different methods highlight that soil moisture is one of the key players in determining autumn photosynthetic phenological processes in subtropical forests. To comprehensively understand autumn phenological processes, in‐situ manipulative experiments are urgently needed to quantify the contributions of different environmental and physiological factors in regulating plants' response to ongoing climate change. [ABSTRACT FROM AUTHOR]

Caryota obtusa of Arecaceae is a fascinating palm tree native to southwestern China, India, Myanmar, Thailand, Laos and Vietnam. It is an economically important and threatened species and appears as a canopy dominant in some karst areas in Yunnan. We aim to clarify the forest structure, species diversity, population status and regeneration dynamics of C. obtusa in the karst forest ecosystem of Yunnan, China. We established 56 vegetation plots dominated by C. obtusa in 10 counties of southern Yunnan. Based on the plot data, we analyzed the community stratification, floristic composition and C. obtusa 's population structure. We used questionnaires to interview local people and recorded the human activity history in C. obtusa -dominated forests. Caryota obtusa palm forests were distributed on limestone mountain slopes and gullies. There were seven forest community types. The stratification of each community included arborous layer, shrub layer and understory. The communities had rich species composition. For all the plots as a whole of each community type, Shannon–Wiener diversity index of either woody or herbaceous species ranged from 2.1 to 3.8. The diameter at breast height (DBH)-class frequency distribution of C. obtusa was a multimodal type. The regeneration was sporadic and dependent on intermediate natural disturbances. In the current population structure, a number of C. obtusa trees with small DBHs consisted mainly of the forest communities with no or a slight degree of human disturbances. Intensive human activities terribly hindered recruitment of C. obtuse , followed by the medium intensity of human activities. [ABSTRACT FROM AUTHOR]

Pinus yunnanensis forest is a unique forest type in southwest China and one of the main forest types in Yunnan Province, which also has great ecological, economic and social significance. Understanding the changes in the stoichiometric characteristics is a key to study the nutrient cycling, limiting factors and stability mechanisms of the forest ecosystem. However, the stoichiometric characteristics, stability of the ecosystem of P. yunnanensis natural forests and whether they are limited by nutrients are still poorly understood. Based on a K-S test, ANOVA analysis and OLS regression analysis, we analyzed the concentrations of leaf C, N and P in 48 woody species of natural P. yunnanensis forests from 122 plots to explore the pattern of leaf C:N:P stoichiometry. Our results showed that the mean values of leaf C, N and P plus C:N, C:P and N:P for the 48 woody species were 451.12, 11.05 and 1.11 mg/g and 45.03, 496.98 and 11.27, respectively. The coefficients of variation of leaf C, N and P plus C:N, C:P and N:P were 5.29%, 36.75%, 51.53%, 29.63%, 43.46% and 41.68%, respectively. The geometric mean values of leaf N, P and N:P were 10.49 and 1.00 mg/g and 10.51, respectively. Leaf C and N, and C and P relationships showed significant negative correlations, but a significant positive correlation was observed between leaf N and P. There were significant differences in leaf N and C:N across functional groups. There were significant differences in leaf C and P between evergreen and deciduous, conifer and broadleaf trees. Significant differences in leaf C:P were only observed between evergreen and deciduous trees, and significant differences in leaf N:P were observed between conifer and broadleaf trees. The relatively low N:P in all sampled trees indicated that N was a limiting factor in the distribution of natural P. yunnanensis forests. However, the higher leaf C:N and C:P ratios indicated that the P. yunnanensis natural forest ecosystem was in a relatively stable state. [ABSTRACT FROM AUTHOR]

Summary: The adoption of diverse resource acquisition strategies is critical for plant growth and species coexistence. Root phosphatase is of particular importance in the acquisition of soil phosphorus (P), yet it is often overlooked in studies of root trait syndromes.Here, we evaluated the role of root phosphatase activity (RPA) within the root economics space and the order‐based variation of RPA, as well as the correlations between RPA and a suite of leaf traits and soil properties over a range of evergreen tree species in a subtropical forest.Root phosphatase activity exhibited a high degree of inter‐specific variation. We found that there were two leading dimensions of the multidimensional root economics space, the root diameter–specific root length axis (collaboration trait gradient) and the root tissue density–root nitrogen concentration axis (classical trait gradient), and RPA aligned with the former. Root phosphatase activity is used as a 'do it yourself' strategy of soil P acquisition, and was found to be inversely correlated with mycorrhizal colonization, which suggests a trade‐off in plant P acquisition strategies. Compared with soil and foliar nutrient status, root traits mattered most for the large inter‐specific changes in RPA. Furthermore, RPA generally decreased from first‐ to third‐order roots.Taken together, such diverse P‐acquisition strategies are conducive to plant coexistence within local forest communities. The use of easily measurable root traits and their tight correlations with RPA could be a feasible and promising approach to estimating species‐specific RPA values, which would be helpful for better understanding plant P acquisition and soil P cycling. See also the Commentary on this article by Yaffar et al., 234: 773–775. [ABSTRACT FROM AUTHOR]

Model systems approaches search for commonality in patterns underlying biological diversity and complexity led by common evolutionary paths. The success of the approach does not rest on the species chosen but on the scalability of the model and methods used to develop the model and engage research. Fine-tuning approaches to improve coral cell cultures will provide a robust platform for studying symbiosis breakdown, the calcification mechanism and its disruption, protein interactions, micronutrient transport/exchange, and the toxicity of nanoparticles, among other key biological aspects, with the added advantage of minimizing the ethical conundrum of repeated testing on ecologically threatened organisms. The work presented here aimed to lay the foundation towards development of effective methods to sort and culture reef-building coral cells with the ultimate goal of obtaining immortal cell lines for the study of bleaching, disease and toxicity at the cellular and polyp levels. To achieve this objective, the team conducted a thorough review and tested the available methods (i.e. cell dissociation, isolation, sorting, attachment and proliferation). The most effective and reproducible techniques were combined to consolidate culture methods and generate uncontaminated coral cell cultures for ~7 days (10 days maximum). The tests were conducted on scleractinian corals Pocillopora acuta of the same genotype to harmonize results and reduce variation linked to genetic diversity. The development of cell separation and identification methods in conjunction with further investigations into coral cell-type specific metabolic requirements will allow us to tailor growth media for optimized monocultures as a tool for studying essential reef-building coral traits such as symbiosis, wound healing and calcification at multiple scales. [ABSTRACT FROM AUTHOR]

Tunable elastic interface states in soft materials have been successfully observed in experiments recently, which provides great application potentials in dynamic vibration energy‐harvesting devices or mechanical control of soft robotics. However, the generation of the proposed tunable elastic interfacial states relies on two differently deformed soft periodic phononic crystals, and complicated mechanical loadings and external installations are inevitable, which are indeed difficult to generate and manipulate. Herein, the dynamically adjustable elastic localized states are implemented in a more reliable and convenient way, which is readily modulated simply through compressing or stretching a mirror‐symmetric metamaterial composite simultaneously. The primitive cell of the soft periodic structures is inspired by the symmetry‐broken hexagonal boron nitride structure. Repeatable and reversible frequency shift and switch on–off characteristics of the interface states are observed during the dynamical regulation process, which is used in the dynamic elastic filter or divider devices. The feasibility of utilizing mirror operation to produce the interface states is clearly demonstrated, which effectively reduces the geometry and configuration design during the manufacturing process. The mirror method is also generalized to other periodic photonic and phononic crystals for the generation of additional multiple tunable interface states. [ABSTRACT FROM AUTHOR]

Selective logging strongly affects forest structure and functions, which has direct and indirect effects on the soil microbial community. However, the effect of selective logging on soil microbial community composition remains unclear. We analyzed the soil microbial diversity and community composition in a pine (Pinus yunnanensis) forest using the Illumina platform for bacterial and fungal sequencing. The results showed that selective logging significantly altered most soil properties and stand attributes. Dominant phyla abundance varied significantly with change of selective logging intensity, affecting soil microbial community composition. The diversity of bacterial community decreased with the increase of selective logging intensity, whereas the diversity of fungi initially decreased and then increased. Soil properties accounted for most of the variation in the soil microbial communities, followed by stand attributes. Stand density (SD), soil pH, and soil moisture directly influenced the diversity of the bacterial communities, and understory species richness (USR), soil organic carbon (SOC), and soil hydrolysable nitrogen (HN) also directly influenced bacterial community composition. However, selective logging intensity affected the diversity and composition of the bacterial communities indirectly via SD, soil pH, HN, SOC, and USR. Similarly, the intensity of selective logging directly affected the diversity of fungal communities and also showed indirect effect on it via SD, soil pH, SOC, HN, C:N ratio, and soil available potassium. Further, selective logging intensity indirectly affected fungal community composition via soil available phosphorus. Our findings could be used to predict the change in the soil microbial community for the management of P. yunnanensis forest. [ABSTRACT FROM AUTHOR]

Abstract: Acoustic metasurfaces that can manipulate and control sound waves at 2D subwavelength scales open new avenues to unusual applications, such as asymmetric transmission, super‐resolution imaging, and particle manipulation. However, the long‐standing goals of pushing frontier metamaterials research into real practice are still severely constrained by cumbersome configuration, large acoustic loss, and rigid structure of the existing metamaterials. An ultrathin metasurface (10–300 µm in thickness, up to ≈λ/650, λ the wavelength) that is capable of imparting sound wave with a nontrivial phase shift with high transmittance (>80%) in the range of 5–30 kHz is fabricated here. The metasurface is comprised of a porous network of soft polymer fiber/rigid beads that are physically equivalent to crosslinked spring‐mass resonators. Moreover, the traditional paper‐cutting art to carve the ultrathin metasurface into hollow‐out patterns is incorporated, resulting in a variety of remarkable functions, including acoustic vortex, focusing, and super‐resolution. The hollow‐out patterning approach innovates the traditional one‐step metadevice fabrication process into two separated steps: 1) fabrication of ultrathin metasurfaces; 2) hollow‐out patterning of metasurfaces. The strategy opens an avenue to mass production of acoustic metadevices, shedding light on the applications of the metamaterials in acoustic cloaking, acoustic positioning, and particle manipulation. [ABSTRACT FROM AUTHOR]

• Rare species exhibited higher functional richness and functional evenness; • Functional divergence has the greatest impact on ecosystem multifunctionality; • Rare species contribute more to ecosystem multifunctionality from a functional view. Global environmental change and increased human activities have led to rare species being given vulnerable status, as well as species losses and extinctions in recent years. However, most of the species in the community are rare species and they usually harbor unique functional traits that disproportionately contribute to community functional diversity. Numerous studies have also shown that functional diversity is a better predictor of ecosystem functioning than species diversity. Consequently, the evaluation of functional diversity of rare species and their contribution to ecosystem function is essential for the conservation of rare species. In this study, differences in functional diversity between rare and common plant species were analyzed based on functional diversity indices and species richness metrics in 30 1-ha plots comprising monsoonal evergreen broad-leaved forest in Pu'er City in the Yunnan Province of China. The roles of functional diversity of rare and common species in affecting ecosystem functions were also evaluated, in addition to the extent that either species group contributes to ecosystem functions or multifunctionality. The results indicated that functional diversity metrics including functional evenness and functional richness of rare species were higher than for common species in this subtropical forest. In addition, the functional diversity indices of rare species contributed greater to most ecosystem functions compared to those of common species. Moreover, the functional divergence of both rare and common species exerted obvious effects on ecosystem multifunctionality, although rare species exerted greater overall contributions. Rare species in the forest community of this study exhibited higher functional diversity and played a more important role in ecosystem multifunctionality via their diverse functional traits. Based on these results, it is necessary to focus greater conservation efforts on rare plants in a community. [ABSTRACT FROM AUTHOR]

The relationship between biodiversity and biomass is an essential element of the natural ecosystem functioning. Our research aims at assessing the effects of species richness on the aboveground biomass and the ecological driver of this relationship in a primary Pinus kesiya forest. We sampled 112 plots of the primary P. kesiya forests in Yunnan Province. The general linear model and the structural equation model were used to estimate relative effects of multivariate factors among aboveground biomass, species richness and the other explanatory variables, including climate moisture index, soil nutrient regime and stand age. We found a positive linear regression relationship between the species richness and aboveground biomass using ordinary least squares regressions. The species richness and soil nutrient regime had no direct significant effect on aboveground biomass. However, the climate moisture index and stand age had direct effects on aboveground biomass. The climate moisture index could be a better link to mediate the relationship between species richness and aboveground biomass. The species richness affected aboveground biomass which was mediated by the climate moisture index. Stand age had direct and indirect effects on aboveground biomass through the climate moisture index. Our results revealed that climate moisture index had a positive feedback in the relationship between species richness and aboveground biomass, which played an important role in a link between biodiversity maintenance and ecosystem functioning. Meanwhile, climate moisture index not only affected positively on aboveground biomass, but also indirectly through species richness. The information would be helpful in understanding the biodiversity-aboveground biomass relationship of a primary P. kesiya forest and for forest management. [ABSTRACT FROM AUTHOR]

Porcine reproductive and respiratory syndrome virus (PRRSV) is the leading virus known to cause massive economic loss in pig industry worldwide. In our previous study, transcriptional profiling of PRRSV-infected lung tissue of Tongcheng and Landrane pigs, which have highly pathogenic PRRSV (HP-PRRSV) susceptibility differences, showed differential expression of Rab11a. The small GTPase Rab11a regulates intracellular membrane trafficking events involved in autophagy. However, the involvement of the convergence of endosomal Rab11a and autophagy pathways during PRRSV infection is still unclear. In this study, we demonstrated that PRRSV infection induced complete autophagy and up-regulated the expression of Rab11a. Furthermore, interference of the expression of Rab11a resulted in the accumulation of endogenous LC3-II and p62, indicating that Rab11a played a vital role in autophagosome maturation. Silencing of Rab11a resulted in a compromise the expression of intracellular viral NSP2 and ORF7. Besides, confocal microscopy analysis showed that viral NSP2 was colocalized with Rab11a in Marc145 cells. Collectively, our findings revealed that Rab11a acted as a proviral host factor that benefited PRRSV replication in a manner that correlates with autophagy. [ABSTRACT FROM AUTHOR]

Highly pathogenic porcine reproductive and respiratory syndrome virus (HP-PRRSV) that emerged from classic PRRSV causes more severe damage to the swine industry. The earlier reports indicating inhibition of interferon-β ( IFN-β) expression by PRRSV through total blockage of IFN-regulatory factor 3 (IRF3) nuclear translocation made us investigate the mechanism of IFN-β expression in HP-PRRSV infection. For this purpose, the IRF3 nuclear translocation in the control group [Poly (I:C)] and test group [Poly (I:C)+HP-PRRSV] was detected by immunofluorescence, and the results showed that IRF3 nuclear translocation in cells with PRRSV was weaker than cells without PRRSV, which was different from the previous study. In addition, the IFN-β mRNA and protein expression was observed to be inhibited by HP-PRRSV along with decreased IRF3 mRNA and total protein, and IRF3 nuclear translocation of test group was suppressed in MARC-145 and porcine alveolar macrophage cells in comparison with the control group. The quantity of phosphorylated IRF3 protein was also reduced after HP-PRRSV infection. However, CREB-binding protein ( CBP) expression did not change between the control and test group. These results indicate that the inhibition of IFN-β expression is mainly due to the quantitative change in the amount of phosphorylated IRF3 in the cytoplasm, but not dependent on the complete blockage of IRF3 nuclear translocation or the restraining of CBP expression in the nucleus by HP-PRRSV. [ABSTRACT FROM AUTHOR]

Autophagy and apoptosis play essential roles 'in virus infection. Our study was performed to investigate the interplay between autophagy and apoptosis in PRRSV replication. In our present study, autophagy and apoptosis were induced by PRRSV infection. Viral replication was dampened/attenuated by autophagy deficient and potentiated by apoptosis inhibition. Furthermore, PRRSV replication was restored by apoptosis inhibition in autophagy deficient cells. Taken together, our findings unveil the functional relationship between autophagy and apoptosis during PRRSV replication. [ABSTRACT FROM AUTHOR]

Autophagy and apoptosis play significant roles in PRRSV infection and replication. However, the interaction between these 2 processes in PRRSV replication is still far from been completely understood. In our studies, the exposure of MARC-145 cells to PRRSV confirmed the activation of autophagy and subsequent induction of apoptosis. The inhibition of autophagy by 3-methyladenine (3-MA) caused a significant increase in PRRSV-induced apoptosis, showing a potential connection between both mechanisms. Moreover, we observed an increase in Bad expression (a pro-apoptotic protein) and Beclin1 (an autophagy regulator) in virus-infected cells up to 36h. Co-immunoprecipitation assays showed the formation of Bad and Beclin1 complex in PRRSV infected cells. Accordingly, Bad co-localized with Beclin1 in MARC-145 infected cells. Knockdown of Beclin1 significantly decreased PRRSV replication and PRRSV-induced autophagy, while Bad silencing resulted in increased autophagy and enhanced viral replication. Furthermore, PRRSV infection phosphorylated Bad (Ser112) to promote cellular survival. These results demonstrate that autophagy can favor PRRSV replication by postponing apoptosis through the formation of a Bad-Beclin1 complex. [ABSTRACT FROM AUTHOR]

The objectives of this study were to estimate changes of tree carbon (C) and soil organic carbon (SOC) stock following a conversion in land use, an issue that has been only insufficiently addressed. For this study, we examined a chronosequence of 2 to 54-year-old Pinus kesiya var. langbianensis plantations that replaced the original secondary coniferous forest (SCF) in Southwest China due to clearing. C stocks considered here consisted of tree, understory, litter, and SOC (0–1 m). The results showed that tree C stocks ranged from 0.02±0.001 Mg C ha-1 to 141.43±5.29 Mg C ha-1, and increased gradually with the stand age. Accumulation of tree C stocks occurred in 20 years after reforestaion and C stock level recoverd to SCF. The maximum of understory C stock was found in a 5-year-old stand (6.74±0.7 Mg C ha-1) with 5.8 times that of SCF, thereafter, understory C stock decreased with the growth of plantation. Litter C stock had no difference excluding effects of prescribed burning. Tree C stock exhibited a significant decline in the 2, 5-year-old stand following the conversion to plantation, but later, increased until a steady state-level in the 20, 26-year-old stand. The SOC stocks ranged from 81.08±10.13 Mg C ha-1 to 160.38±17.96 Mg C ha-1. Reforestation significantly decreased SOC stocks of plantation in the 2-year-old stand which lost 42.29 Mg C ha-1 in the 1 m soil depth compared with SCF by reason of soil disturbance from sites preparation, but then subsequently recovered to SCF level. SOC stocks of SCF had no significant difference with other plantation. The surface profile (0–0.1 m) contained s higher SOC stocks than deeper soil depth. C stock associated with tree biomass represented a higher proportion than SOC stocks as stand development proceeded. [ABSTRACT FROM AUTHOR]

The regulation of viral replication is under control of miRNAs and their target genes. Several articles report the cross-talk between host and virus. The drastic effects of Porcine reproductive and respiratory syndrome virus (PRRSV) pressed us to investigate the expression profiling of miRNAs and immunity related genes during PRRSV infection. This was performed by qPCR in MARC145 cells during PRRSV infection. It was observed that miRNAs and genes show different expression patterns at different time points during PRRSV infection. The early infected stage was accompanied with increased expression of some miRNAs including miR-204, miR-21, miR-181a, miR-29 while a decrease was observed for the same in late infection stage. The opposite condition also existed in parallel. An interesting observation was seen when miR-145 was strongly induced by PRRSV infection, whereas miR-127 expression was significantly reduced in all infection points. Taken together, our studies have revealed that the expressions of miRNAs and immune-related genes were regulated in PRRSV infected MARC-145 cells and had important roles in the immune response, providing a basis for further investigations. [ABSTRACT FROM AUTHOR]

Soil microbial communities play an important role in maintaining the ecosystem during forest secondary succession. However, the underlying mechanisms that drive change in soil microbial community structures during secondary succession remain poorly defined in species-rich subtropical coniferous forests. In this study, Illumina high-throughput sequencing was used to analyze the variations in soil microbial community structures during forest secondary succession in subtropical coniferous forests in China. The role of soil properties and plant diversity in affecting soil bacterial and fungal communities was determined using random forest and structural equation models. Highly variable soil microbial diversity was observed in different stages of secondary succession. Bacterial community diversity rose from early to middle and late successional stages, whereas fungal community diversity increased from early to middle successional stages and then declined in the late stage. The relative abundance of Acidobacteria, Gemmatimonadetes, Eremiobacterota(WPS-2), Rokubacteria, and Mortierellomycota increased during succession, whereas the relative abundance of Ascomycota and Mucoromycota decreased. The community composition and diversity of the soil microbial community were remarkably influenced by plant diversity and soil properties. Notably, tree species richness (TSR) displayed a significant and direct correlation to the composition and diversity of both bacterial and fungal communities. The carbon-to-nitrogen (C:N) ratio had a direct impact on the bacterial community composition and diversity, and pH had a marked impact on the fungal community composition and diversity. Furthermore, succession stage and plant diversity indirectly impacted the composition and diversity of soil bacterial and fungal communities via soil properties. Overall, it can be concluded that soil intrinsic properties and plant diversity might jointly drive the changes in soil microbial community composition and diversity during secondary succession of subtropical coniferous forests. [ABSTRACT FROM AUTHOR]

• Species richness drove mainly ecosystem multifunctionality in a subtropical coniferous forest in southwest, China. • Stand structural complexity mediated relationship between species richness and ecosystem multifunctionality. • Total woody species abundance and dominant species abundance indicated little effect on shaping ecosystem multifunctionality. Forests can provide multiple ecosystem functions simultaneously that are related to biomass production, soil carbon stock, and nutrient cycling, and plant diversity is often important for the maintenance of ecosystem multifunctionality (EMF). However, the underlying mechanisms involved in regulating relationships between species richness and abundance and EMF in a subtropical coniferous forest still remain unclear. Using a randomization test and structural equation model, we show that multiple plant diversity attributes, stand structural complexity, dominant species, and soil conditions affect EMF from 94 plots in Pinus kesiya dominant stands in southwest China. Our results indicate that the direct effects of species richness on EMF were stronger than the effects of woody individual abundance, and species richness increased with increasing EMF. By contrast, EMF declined with increasing total woody species abundance, while functional diversity and dominant species abundance did not exhibit significant effects on EMF. However, Castanopsis echidnocarpa abundance indirectly increased EMF via species richness and total woody species abundance. Simultaneously, our findings suggest that stand structural complexity mediated the relationship between plant diversity and EMF, and species richness, total woody species abundance, and EMF increased strongly with increasing stand structural complexity. Higher soil pH and soil water content were associated with greater stand structural complexity and EMF, which were important drivers in explaining variation in EMF. Our results show that higher species richness promoted EMF provisioning, and provide critical insights to predicting the possible consequences of EMF with a change in biotic and abiotic factors. [ABSTRACT FROM AUTHOR]