The Research Unit Forest and Soil Ecology assesses the impact of climate change and management on forests and their soils. The group Critical Zone dynamics is looking for a

You will work within the recently funded SNSF project FIRE ("Fire Impacts on the Response of terrestrial Ecosystems"). Wildfires are a natural component of the global carbon cycle, but their frequency, intensity, and severity are increasing with climate change. This project investigates how wildfires affect carbon cycling and transit times at the landscape scale, particularly in the deeper unsaturated zone and in groundwater, and over longer periods of time. You will be part of an interdisciplinary team of collaborators based in Switzerland and the USA, and conduct fieldwork in caves in remote locations of the USA that were recently affected by burning. The focus of this PhD will be on characterizing and quantifying carbon sources and transit times across the critical zone (soil to groundwater and laterally). These results will be linked with datasets produced by the other team members who will focus on chemical transformation and subsurface transport of organic compounds, microbial community responses, and the reconstruction of long-term fire impacts using cave mineral deposits. Besides fieldwork, your tasks will include conducting geochemical analysis on fluid, gaseous and solid samples, in particular radiocarbon analysis. Your workplace will be at the Swiss Federal Research Institute WSL in Birmensdorf and you will be enrolled as a PhD student at ETH Zurich. Given the collaborative nature of the project, research visits (field and lab work, scientific exchange) to our partner institutes in the USA are expected and encouraged.