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Subalpine peat wetlands are extremely sensitive to global environmental changes and anthropogenic disturbances. Unlike most other biological groups, plant species can possess dormant life‐history stages such as the soil seed bank (SSB), which may help plant communities to resist or at least postpone the detrimental impact of disturbance. This study investigates the potential for SSB to achieve this along a soil moisture gradient. Species richness and density of SSB were significantly lower by 31.9% and 47.2% in wetland, and 35.1% and 68.1% in swamp meadow in comparison with steppe meadow, respectively. Soil moisture content did not directly affect the density and species richness of SSB, whilst had indirect effects on density and species richness via affecting vegetation and soil pH. SSB composition was less responsive to soil moisture changes than plant community composition. Furthermore, compositional trends in the annual plant SSB were weaker than in the aboveground vegetation along the soil moisture gradient. The similarity between SSB and vegetation significantly declined with increasing soil moisture content. High SSB diversity and compositional similarity between the vegetation and SSB may provide a potentially important functional buffer against the impact of ongoing moisture changes on plant communities in wetlands. Dormant life‐history stages can therefore be important sources of diversity in changing environments. Furthermore, although SSB has low regeneration potential for the aboveground vegetation communities in subalpine peat wetlands, the SSB would still not be a neglected factor for the restoration of propagule diversity after disturbance in wetlands if hydrology is restored. [ABSTRACT FROM AUTHOR]

Plastic film mulching can affect soil organic carbon (C) lability in semiarid regions. Arbuscular mycorrhizal (AM) fungi represent an important route for plant‐derived C into soil and can be influenced by agricultural practices. Whether the changes of AM fungal community affect soil organic C sequestration is a fundamental question in semiarid environments. To this end, we conducted two field experiments investigating the influence of a Funneliformis mosseae inoculation and mycorrhizal‐suppression using benomyl application on maize growth, soil fractions of organic C, AM fungal parameters, including diversity profiling using the Illumina MiSeq. The results showed that AM fungal community composition was significantly altered by plastic film mulching and fungicide applications, soil organic C fractions and nitrogen were most important factors in influencing the AM fungal community. AM fungal inoculation significantly increased particulate organic C and light fraction organic C content, due to enhance dextramatrical hyphal length (EMH), glomalin content, and root biomass. Conversely, fungicide applications reduced labile organic C, possibly through decreasing EMH, glomalin content and soil AM fungal diversity. Increases in relative abundance of F. mosseae in rhizosphere soil, coupled with increases in AM fungal root colonization from F. mosseae inoculation indicates successfully established by outcompeting the existing natural AM fungal community. Plastic film mulching resulted in significant increases in maize yield and water use efficiency, and AM fungal inoculation was found to amplify the effects. Thus, AM fungal inoculation may act as an effective farming practice to improve soil organic C fractions, which can boost maize productivity. [ABSTRACT FROM AUTHOR]

Aiming to understand the responses of soil seed bank to different water levels, we investigated vegetation and soil seed bank along a water level gradient (frequently flooded area, unflooded area) on the floodplain wetland of Juzhang River. We used the structural equation model to explore the direct and indirect effects of water level on soil seed bank, and used non-metric multidimensional scaling (NMDS) to assess the role of soil seed bank for vegetation regeneration. The results showed that the density of transient and persistent seed banks at unflooded area was 36.9% and 7.8% higher than that of frequently flooded area, respectively. Shannon index and Pielou index of seed bank and vegetation were significantly affected by water level and sampling location. Water level significantly affected the similarity between seed bank and aboveground vegetation, and the similarity of persistent seed bank with aboveground vegetation was significantly higher than that with transient seed bank. Structural equation model showed that water level had a direct effect on seed bank density, and indirect effects on density and richness of seed bank via affecting soil pH and NH 4 + -N content. NMDS results showed that there was no significant difference in the composition of the persistent seed bank and vegetation community in autumn under different water levels, but water level significantly changed the community composition of transient seed bank. Transient seed bank was affected by the vegetation and soil property, while persistent seed bank was determined by aboveground vegetation and water level. Although soil seed bank had low regeneration potential for the vegetation communities in floodplain wetlands, soil seed bank could not be neglected during the restoration of propagule diversity after disturbance in wetlands. Persistent seed bank would be an importance source of diversity of propagules for floodplain wetlands restoration following disturbance.