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European dry thin-soil calcareous grasslands (alvars) are species-rich semi-natural habitats. Cessation of traditional management, such as mowing and grazing, leads to shrub and tree encroachment and the local extinction of characteristic alvar species. While soil microbes are known to play a critical role in driving vegetation and ecosystem dynamics, more information is needed about their composition and function in grasslands of different dynamic stages. Here we assess the composition of soil fungal, prokaryotic, and plant communities using soil environmental DNA from restored alvar grasslands in Estonia. The study areas included grasslands that had experienced different degrees of woody encroachment prior to restoration (woody plant removal and grazing), as well as unmanaged open grasslands. We found that, in general, different taxonomic groups exhibited correlated patterns of between-community variation. Previous forest sites, which had prior to restoration experienced a high degree of woody encroachment by ectomycorrhizal Scots pine, were compositionally most distinct from managed open grasslands, which had little woody vegetation even prior to restoration. The functional structure of plant and fungal communities varied in ways that were consistent with the representation of mycorrhizal types in the ecosystems prior to restoration. Compositional differences between managed and unmanaged open grasslands reflecting the implementation of grazing without further management interventions were clearer among fungal, and to an extent prokaryotic, communities than among plant communities. While previous studies have shown that during woody encroachment of alvar grassland, plant communities change first and fungal communities follow, our DNA-based results suggest that microbial communities reacted faster than plant communities during the restoration of grazing management in alvar grassland. We conclude that while the plant community responds faster to cessation of management, the fungal community responds faster to restoration of management. This may indicate hysteresis, where the eventual pathway back to the original state (grazed ecosystem) differs from the pathway taken towards the alternative state (abandoned semi-natural grassland ecosystem). [ABSTRACT FROM AUTHOR]

Research over the past decade has shown that quantifying spatial variation in ecosystem properties is an effective approach to investigating the effects of environmental change on ecosystems. Yet, current consensus among scientists is that we need a better understanding of short‐ and long‐term (temporal) variation in ecosystem properties to plan effective ecosystem management and predict future ecologies.Trait‐based approaches can be used to reconstruct ecosystem properties from long‐term ecological records and contribute significantly to developing understandings of ecosystem change over decadal to millennial time‐scales.Here, we synthesise current trait‐based approaches and explore how organisms' functional traits (FTs) can be scaled across time and space. We propose a framework for reconstructing long‐term variation in ecosystems by means of analysing FTs derived from palaeoecological datasets. We then summarise challenges that must be overcome to reconcile trait‐based approaches with palaeo‐datasets. Finally, we discuss the benefits and limitations of trait‐based reconstructions of ecosystem temporal dynamics and suggest future directions for research.Reconstructing environmental properties through time vis‐à‐vis FTs can be separated into two parts. The first is to record trait data for organisms present in modern ecosystems, and the second is to reconstruct temporal variability in FTs from palaeoecological datasets, capturing changes in trait composition over time. Translating palaeoecological datasets into FTs is challenging due to taphonomic, taxonomic and chronological uncertainties, as well as uniformitarian assumptions. Explicitly identifying and addressing these challenges is important to effectively calculate changes in FT through time.Palaeo‐trait research offers insights into questions related to short‐ and long‐term ecosystem functioning, environmental change and extinction and community assembly rules across time. As work in this area matures, we expect that trait‐based approaches integrating palaeoecology and neo‐ecology will improve understanding of past ecologies and provide a deeper insight of their implications for present‐day and future ecosystem management and conservation. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]