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• 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]

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]

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]

• 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]

• Woody species richness played a vital role in driving soil fungal community structure. • Higher ectomycorrhizal fungi abundance accompanied by lower undefined saprotrophic fungal abundance. • Change of ericoid mycorrhizal fungi abundance was dependent on understory species composition. • Endophytic fungal abundance increased with the forest secondary succession. Forest secondary succession alters plant diversity and soil properties in the forest ecosystems; however, effects of this process on the soil fungal community structure are poorly understood. We used Illumina high-throughput sequencing to identify soil fungal community during forest secondary succession (including 30-, 45-, 60-, and 80-year-old stands) in the Pinus yunnanensis forest. The aims were to explore how plant diversity and soil properties drive soil fungal community structure and elucidate the role of fungal guilds in integrating the linkages of plant diversity and soil properties with forest secondary succession. Our study found that forest secondary succession changed woody species composition, richness, and soil properties, furthermore, this also affected significantly soil fungal diversity, community composition, and the abundances of the different functional guilds along the forest secondary succession. Soil fungal diversity initially increased up to the 60-year-old stand, and then decreased with forest secondary succession. The main phyla included Agaricomycetes, Leotiomycetes, Mortierellomycetes, and Eurotiomycetes, and indicator phyla varied differently with forest secondary succession. Soil fungal community could be clearly divided into the four successional stages. Forest secondary succession affected significantly soil fungal diversity via altering woody species richness and soil properties. Mycorrhizal, saprotrophic, and endophytic fungi interacted differently with forest secondary succession. Ectomycorrhizal fungi (ECM) played a vital role in driving forest secondary succession, and greater ECM fungal abundance could drive the forest secondary succession process through changes in the ECM plant composition. ECM plant community composition displayed different effects on ECM fungal abundance. As a result, ECM fungal abundance increased with a higher abundance of Castanopsis orthacantha , and decreased with a higher abundance of P. yunnanensis. Ericoid mycorrhizal fungal abundance reached its maximum in the 45-year-old stand and then decreased, which could provide valuable information for understory restoration. Undefined saprotrophic fungal abundance decreased with increasing forest secondary succession, accompanied by an increase of ECM fungal abundance, while endophytic fungi increased with forest secondary succession. Our findings suggested that plant-fungal symbionts and environmental selection posed an important constraint in assembly of soil fungal community and functional guild abundances. Altogether, these results provided new insights for predicting shifts in plant and soil fungal community strategies with the forest secondary succession in the P. yunnanensis forest. [ABSTRACT FROM AUTHOR]

• Tree growth is highly dependent on local climate rather than on large-scale climate change. • Climate drivers for tree growth are redistributed under climate warming. • The sensitivity of tree growth to climate under favorable conditions is more stable than in harsh ones. The relative influence of energy and water availability on tree growth at specific sites under warming conditions remains insufficiently understood on the Yunnan Plateau, which obstructs the rational selection and development of forest management measures in the context of climate change. In this study, a dendroecological investigation was conducted in four sites on the Yunnan Plateau to evaluate growth trends and climate responses of Pinus yunnanensis under warming and drought stress across cold-dry (CD), warm-humid (WH), warm (WR), and hot-dry (HD) zones. The effects of energy and water availability on the radial growth of P. yunnanensis varied in different sites and showed site-specific characteristics. The radial growth of P. yunnanensis in the CD zone benefited from rising temperatures, especially in the pre-growing season and core growing season. However the radial growth of P. yunnanensis in the WH zone was restricted by excess water in the core growing season. The radial growth of P. yunnanensis in the WR and HD zones became increasingly limited by temperature and drought stress, and the growth switched from responding to energy stress to moisture stress. The sensitivity of P. yunnanensis to climate factors in the warm-humid zone and humid seasons was relatively stable; in contrast, this species was vulnerable to warming and drought stress under harsh growth conditions and showed considerable instability. Intense warming in the future may cause a significant variation of tree growth response to climate. It would trigger a noticeable redistribution effect of energy and water availability on forest growth, which motivates assessments of climate-growth relationships, not only at large spatial scales, but also in specific sites. This research provides a basis for the adoption of effective forest management measures for specific sites according to their response characteristics associated with the distribution of climate drivers. [ABSTRACT FROM AUTHOR]

• Woody species richness was the main driver in shaping EMF and function indices. • Fungal diversity played an important role in driving EMF depending on main functional guilds. • Phylogenetic diversity indicated significant positive effect on the water regulation. • Multiple biodiversity attributes and soil conditions determined the supply of multiple ecosystem functions. Various biodiversity attributes contribute to ecosystem multifunctionality (EMF) in different ways in terrestrial ecosystems. The relative influence of biodiversity and abiotic factors in driving EMF simultaneously remains relatively unclear. We evaluated the effects of woody species richness along with phylogenetic, functional, fungal, and bacterial diversity as well as abiotic factors on EMF. The analysis also included a review of function indices (including biomass production, water regulation, carbon stock, and nutrient cycling) along the elevation gradient in the Jinsha River valley, southwestern China, based on the bivariate relationship, random forest model, structural equation model (SEM), randomization tests, and redundancy analysis. The results showed that EMF increased with increases in woody species richness, phylogenetic diversity, elevation, and soil water content, while it decreased with increases in bacterial diversity and soil pH. The random forest model showed that elevation, soil pH, soil water content, and woody species richness made the main contribution to EMF and function indices. Further analysis using SEM confirmed these results. Indeed, woody species richness played a relatively important role in driving EMF, biomass production, carbon stock, and nutrient cycling compared to other diversity metrics. Dominant species contributed differently to the EMF and functions. However, phylogenetic diversity also appeared to have a positive effect on water regulation. Simultaneously, as a belowground trophic group, fungal diversity played a vital role in shaping EMF, biomass production, and nutrient cycling, which may be assigned to a change of arbuscular mycorrhizal fungi and ectomycorrhizal fungi along the elevation gradient. In addition, abiotic factors regulated the relationship between biodiversity and EMF. Elevation, soil water content, and soil pH appeared to have direct and indirect effects on the EMF and function indices. Woody species richness, fungal diversity, soil water content, soil pH, and elevation jointly mediated EMF in the Jinsha River valley, whereas woody species diversity was the main driver of EMF and other function indices following the complex environmental conditions. Our result should be useful for land managers involved in ecological restoration in the Jinsha River valley, where biodiversity and soil quality will determine the supply of multiple ecosystem functions. [ABSTRACT FROM AUTHOR]

[Display omitted] • Macadamia-based agroforestry systems influence microbial necromass C and its contribution to SOC. • Soil fungal β diversity controlled and significant negative effect over microbial necromass C and its contribution to SOC. • Woody aboveground biomass indirectly affected microbial necromass C via soil fungal β diversity. Agroforestry management practices governed soil organic carbon (SOC) and microbial community structure in terrestrial ecosystems, yet the effect of these practices on microbial necromass carbon (C) remain poorly understood in a subtropical region. Here, we compared the differences in fungal, bacterial, and microbial necromass C (indicated by amino sugars) and their contributions to SOC among different forest types including macadamia monoculture plantation (MMP) and macadamia-based agroforestry systems intercropping with dasheen (MDAS), konjac (MKAS), and maize (MMAS) in the Lincang city, southwest Yunnan province, China, and assessed the impact of aboveground biomass, soil fertility, and soil microbial community structure on microbial necromass C and its contribution to SOC. Compared with monoculture plantation, macadamia-based agroforestry decreased SOC, and changed significantly soil microbial α diversity, β diversity, and microbial necromass C and its contribution to SOC (P < 0.01). Microbial necromass C and its contribution to SOC were no significant difference between MMP and MMAS. MDAS and MKAS had lower microbial necromass C than MMP (35.11 % and 63.62 %, respectively). SOC increased with increasing soil fungal and microbial necromass C among the agroforestry systems. Soil fertility was the most important factor affecting fungal (41.45 %), bacterial (33.84 %), and microbial necromass C (40.63 %). Importantly, soil fertility and fungal β diversity directly negatively affected soil fungal and microbial necromass C and their contributions to SOC. Furthermore, woody aboveground biomass affected microbial necromass C directly or indirectly via soil fungal β diversity. Overall, our findings suggest that soil fungal β diversity drove microbial necromass C accumulation and its contribution to SOC in a macadamia-based agroforestry systems, which reveal that sowing crop may be key considerations in mitigating climate change. [ABSTRACT FROM AUTHOR]

Identifying and protecting refugia is a priority for conservation management under projected anthropogenic climate change. We have two main objectives: the first is to explore the spatial (East Asia) and temporal (Last Glacial Maximum to year 2070) distribution patterns of dominant Castanopsis species of evergreen broad-leaved forests, also the relation with their niche breadths; the second is to identify long-term stable refugia for preserving these species and provide a framework of conservation strategies. We find that there is an extraordinary richness with 32 dominant Castanopsis species, and they form both a geographically and climatically almost unbroken connection from ca. 5°N to 38°N, having thus ecological significance. During the Mid-Holocene and, particularly, the Last Glacial Maximum, the predicted suitable areas of the species as a whole were larger than those in the present. By 2070, potentially suitable areas with high richness of dominant Castanopsis species will be reduced by 94.5 % on average. No correlation between species niche breadths and distribution ranges is found, which could be due to regional climate stability. Mountains of southwestern and southern Yunnan in China are identified as climatically long-term stable refugia for 7–9 Castanopsis species. We recommend that these refugia have the highest priority of conservation to prevent their extinction. Our suggested urgent measures include improving the effectiveness of currently protected Castanopsis species and expanding the network of protected areas to cover a larger fraction of the refugia, as well as ensuring Castanopsis species natural regeneration potential in fragmented and natural secondary forest areas. [ABSTRACT FROM AUTHOR]