[1] Semi-volatile organic compounds derived from burned and fresh vascular plant sources and preserved in highaltitude ice fields were detected and identified through use of recently developed analytical tools. Specifically, stir bar sorptive extraction and thermal desorption coupled with gas chromatography/time-of-flight mass spectrometry allowed measurement of multiple biomarkers in small sam...

We propose here to interpret and model peculiar plant morphologies (cushions and tussocks) observed in the Andean Altiplano as localized structures. Such structures resulting in a patchy, aperiodic aspect of the vegetation cover are hypothesized to self-organize thanks to the interplay between facilitation and competition processes occurring at the scale of basic plant components biologically r...

We present the results of pollen analysis performed on an ice core recovered from Nevado Sajama, Bolivia, dated to 25 ka BP. Low pollen concentrations from 25 to 15 ka BP are consistent with the scenario of an expanded ice cap surrounded by sparse vegetation and cold conditions on the Altiplano during the Last Glacial Maximum. After 15 ka BP, more pollen is present and percentages show vegetati...

Natural hydrogen is known to be generated in the crust by water/rock interactions, especially oxidation of iron-rich rock or radiolysis. However, other sources, deeper ones, exist. In context subduction, dehydration slab, destabilization NH4, and hydration mantle wedge above subducting lithosphere may generate H2. We present here a compilation gases central part Pacific subduction results first...