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Grassland afforestation poses a threat to biodiversity beyond land‐use conversion. Diversity patterns are shaped by temporal dynamics, particularly, time since afforestation can decline beta diversity and lead to biotic homogenisation. Our study examines the effect of grassland afforestation on soil prokaryotic and fungal beta diversity. We evaluate the contributions of colonisation and extinction processes to beta diversity, as well as the replacement of endemic species by ubiquitous ones. Along a 200 km climatic gradient in Argentina's Pampas region, we analysed grasslands and mature eucalypt plantations at different times since afforestation. Soil samples were collected at each site and analysed using 16S (V3–V4) and ITS2 amplicon sequencing to identify prokaryotic and fungal communities, respectively. The analyses revealed biotic homogenisation at the transition from grassland to newly planted stands, evidenced by a decrease in intratreatment beta diversity. Increasing time since afforestation did not exacerbate this decline. However, our findings indicate that there are different responses between prokaryotes and fungi. The homogenisation of prokaryotes in young stands is due to the low heterogeneity in colonising communities. On the other hand, the decline in fungal beta diversity is likely caused by other mechanisms beyond extinction or replacement. The study highlights the impacts of the afforestation process on the beta diversity of soil microbial communities of grasslands, affecting taxonomic groups in different ways. Although microbial diversity may be partially restored in time in eucalypt plantations, it is important to investigate its underlying mechanisms and the ecological implications for microbial diversity and its spatial distribution. [ABSTRACT FROM AUTHOR]

Text-analysis tools focused on limnology research allowed us to find three approaches in the analysis of ecosystems services (ES) provided by bacteria, archaea and viruses: (i) a prevalence of taxonomic analyses focused on the relevance of microbial biodiversity in sustaining ES, (ii) studies focused on diversity and functional aspects of bacteria, archaea and viruses and their ES provided and (iii) research focused on disservices. Supporting, regulating and provisioning services were the most discussed. Significant gaps include knowledge about the ecological traits of prokaryotic taxa and viral particles, quantitative information on microbial community-level functions integrated through different ecosystems, and a deeper integration of positive and negative microbial community functional attributes and their feedbacks to ecosystem services provision. Future research should include: (i) development of new bioinformatic tools coupled to theoretical and methodological frameworks leading to a more powerful analysis of metagenomic data, (ii) inclusion of earth observation data for comprehensive modeling of large-scale assessment of ES and its valuation, (iii) advance investigation on the ecological processes that viruses support in the environment and its significance for the ecological performance of microbial communities' services provision. [ABSTRACT FROM AUTHOR]