We use uncrewed-aerial-system-derived optical and infrared data, mineralogical and geochemical analyses of rock samples, and surface degassing measurements to analyze degassing and hydrothermal alteration at the fumaroles of the La Fossa cone, Vulcano island, Italy. We give a detailed view of associated structures and dynamics, such as local alteration gradients, diffuse active units that significantly contribute to the total activity, or effects of permeability reduction and surface sealing. 

This investigation of microbial biogeography in terrestrial mud volcanoes (MVs) covers study sites over a geographic distance of up to 10 000 km across the Eurasian continent. It compares microbial community compositions' coupling with geochemical data across a 3D space. We demonstrate that stochastic processes operating at continental scales and environmental filtering at local scales drive the formation of patchy habitats and the pattern of diversification for microbes in terrestrial MVs.

Soils from an everlasting fire (gas seep) in Sicily, Italy, reveal high relative abundances of novel uncultivated mycobacteria and unique ¹³C-depleted mycocerosic acids (multi-methyl branched fatty acids) close to the main gas seep. Our results imply that mycocerosic acids in combination with their depleted δ¹³C values offer a new biomarker tool to study the role of soil mycobacteria as hydrocarbon consumers in the modern and past global carbon cycle.