Extensifying current land use practices is pivotal to facilitate the transition towards sustainable agriculture in productive grasslands, as it promotes the enhancement of soil biotic communities that support important ecosystem services. To efficiently monitor transition practices, we need improved inventories to measure changes in microbial communities. Microbial Volatile Organic Compounds (mVOCs) are potential biomarkers that can link soil community change to land use extensification (i.e., the reduction of land use intensity), and hence may provide important information on changes in soil processes in transitional productive grasslands. We examine how land use extensification influences the mVOC fingerprint in grassland soils through abiotic and biotic effects, and if mVOC profiles can be linked to bacterial and fungal community composition. As such, we measured mVOCs, soil microbial communities, and soil abiotic parameters in eighteen grasslands that differ in land use intensity type. We show that land use intensity types – conventional, extensive, and semi-natural grasslands – differ in mVOC profiles and chemical classes. Within these grasslands, only fungi showed distinct community compositions between land use intensity types, whereas there were no compositional differences of bacteria. Using Taxon Indicator Threshold Analysis (TITAN), we identified sixteen indicative VOC compounds that markedly varied along the land use extensification gradient. Our results indicate the potential of mVOCs as biomarkers that link productive grassland land use and soil communities, yet these relationships are complex in field situations. Our work, however, identifies a set of mVOCS that change in abundance along the land-use extensification gradient, which has crucial implications for advancing our understanding of the mVOCs as biomarkers for land use extensification in productive grasslands.

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