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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]

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]

• Afforestation could attain higher EMF and multiple functions compared to savanna. • Planted species identity was crucial to successful afforestation. • Soil microbial diversity, but not plant species richness, drove EMF and multiple functions. • Soil microbial network complexity played an important role in maintaining EMF and multiple functions. Increasing aridity over the last six decades has resulted in severe degradation of ecosystem functioning and structure in the dry-hot valley savanna. It remains largely uncertain whether afforestation could recover the ecosystem multifunctionality (EMF) of the previous savanna in this region. Here, we discern key factors maintaining EMF and several specific ecosystem functions in a dry-hot valley in southwest China. We recorded plant traits, soil properties, enzymatic activity, and microbial community structure across 70 plots which included six plantations and one savanna. Afforestation could restore the EMF level of savanna by increasing individual ecosystem functions. However, not all plantations could attain the EMF level (5.29 on average) of the savanna and species identity was important for recovery in EMF and multiple ecosystem functions. Soil microbial diversity, but not plant species richness, drove improvements in EMF and multiple ecosystem functions following afforestation in the savanna. Soil fungal network complexity was the most important regulator of EMF (standardized total effect (STE) = -0.484, P < 0.01), plant biomass (STE = 0.34, P < 0.05) and soil organic carbon (SOC) stock (STE = -0.527, P < 0.01), and soil nutrients (STE = -0.7, P < 0.01), and soil fungal diversity was found to have an indirect effect on EMF (STE = 0.428, P < 0.01), SOC stock (STE = 0.355, P < 0.01), soil nutrients(STE = 0.315, P < 0.01), and decomposition (STE = 0.46, P < 0.01). Soil bacterial network complexity was related to carbon cycling and decomposition. Soil pH and soil water content played important roles in maintaining EMF and multiple ecosystem functions. Our study highlights that soil microbial diversity and network complexity are important predictors driving EMF and multiple ecosystem functions following afforestation in the dry-hot valley savanna. [ABSTRACT FROM AUTHOR]

• Increasing woodland use intensity (WUI) had significant impacts on soil EMF. • WUI can indirectly affect soil EMF through microbial diversity and network complexity. • Soil EMF was regulated by soil microbial diversity and network complexity. • Soil water content mainly affected EMF both in the dry and wet seasons. Global change (e.g., woodland use change) affects ecosystem functioning directly by modifying various physicochemical processes and indirectly by altering biological metabolism and interactions. To determine whether woodland use intensity (WUI) affects soil ecosystem multifunctionality (EMF) via microbial diversity and network complexity and whether the dry and wet season drivers are the same. We analyzed the relationships of soil EMF to soil microbial (bacteria and fungi) diversity and network complexity, considering the WUI in the monsoon evergreen broad-leaved forest in dry and wet seasons in subtropical China. The findings showed that with increasing of WUI, soil microbial (bacteria and fungi) diversity increased, whereas soil EMF decreased. The microbial network complexity decreased in the dry season but increased in the wet season. Soil EMF was jointly regulated by indirect effects from WUI in addition to microbial diversity and network complexity. WUI and abiotic factors can indirectly affect soil EMF through microbial diversity and network complexity, among which soil water content is the main environmental factor affecting soil EMF in dry season, and fungal diversity is the main factor affecting soil EMF in wet season. In addition to demonstrating how multiple anthropogenic drivers differ in their impact via different pathways on soil EMF components, our results will facilitate the prediction of ecosystem responses to multiple simultaneous environmental changes. [ABSTRACT FROM AUTHOR]

• OTU and Chao1 richness indexes were highest in the high plateau and lowest in ridge. • The Shannon diversity index was highest in the ridge and lowest in the valley. • Valley soil fungal networks were best connected among the microtopography types. • Ectomycorrhiza represented the most abundant functional guild in microtopographies. • Microtopography affects the relative contributions of ecological processes. Topography is a critical factor that determines the patterns and assemblages of species diversity in forest communities. Small-scale topography changes are defined as microtopography. Our understanding of the effects of microtopography on soil fungal communities is limited. The objective of this study was to explore the impact of microtopography on soil fungal community diversity, community composition, functional guild, and community assembly. The diversity, composition, and relative abundance of functional guilds were measured using Illumina high-throughput sequencing techniques in five microtopography types (steep slope, less-steep slope, valley, high plateau, and ridge). OTU and Chao1 indexes were the highest in the high plateau and were the lowest in the ridge. The Shannon index was the lowest in the valley, and the highest in the ridge. In the valley, soil fungal networks were more interconnected than they were in any of the other microtopography unit. At the class level, the relative abundance of Agaricomycetes, Eurotionmycetes, and Leotiomycetes were higher in the ridge unit. The relative abundance of ectomycorrhiza, the dominant functional guild, in the ecosystem was as follows: less-steep slope (71.31%), ridge (66.55%), valley (65.83%), steep slope (63.91%), and high plateau (60.09%). Microtopography influenced fungal community diversity and composition more than any other factor and had, varying degrees of influence on the different functional guilds. In every microtopography type, dispersal limitations and drift shaped fungal communities more than other ecological processes. Our findings suggest that microtopography affects soil fungal community diversity and composition, functional guilds, and the relative contributions of ecological processes to soil fungal communities in subtropical monsoon evergreen broadleaf forests. [ABSTRACT FROM AUTHOR]

[Display omitted] • Converting primary forest to agricultural production decreased fungal, bacterial, and total microbial residue C. • Soil fungal abundance increased microbial residue C accumulation. • Soil bacterial abundance declined fungal and total microbial residue C accumulation. • Soil fertility improved fungal, bacterial, and total microbial residue C accumulation. Soil microbes mediate soil organic carbon (SOC) storage by affecting microbial residue carbon (C) in terrestrial ecosystems, a main source of SOC. However, how microbial residue C accumulation changes during the conversion of subtropical primary forest to plantations and the role of soil microbial community structure in regulating these changes remain unclear. Here, effects of conversion from forest on microbial residue C accumulation in three plantations, including tea (Camellia sinensis var. assamica), walnut (Juglans regia), and macadamia (Macadamia integrifolia). We assessed amino sugars content and the relative importance of soil microbial community structure, soil fertility, and aboveground biomass in four forest types in southwest Yunnan province, China. Our results show that total microbial residue C accounted for 27.8 % of SOC on average across all forest types, and fungal residue C contributed more to SOC than bacterial residue C across different forest types. Conversion from primary forest decreased fungal, bacterial, and total microbial residue C content in all plantation types except tea. Microbial residue C contents was significantly lower in the macadamia plantation than in the primary forest and the tea plantation. Fungal and total microbial residue C content increased with increasing soil microbial community composition, soil fungal abundance, and soil fertility. Soil fertility regulated fungal, bacterial, and total microbial residue C accumulation, which was major determinant of microbial residue C via its influence on soil fungal and bacterial abundance. Overall, we found that soil fungal abundance contributed more to microbial residue C accumulation than change in soil microbial community composition. We also found that soil bacterial abundance was negatively correlated with fungal and microbial residue C, while soil fungal abundance was positively related to microbial residue C accumulation. Ascomycota was most important phylum regulating microbial residue C. These findings suggest that soil fungal and bacterial abundance and soil fertility are the principal regulators of microbial residue C accumulation during the conversion from primary forest to different plantations. [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]