SwissSOM

Lead

This study investigates the vulnerability of soil organic carbon (SOC) to climate and human perturbations of Swiss forest, grassland and peatland systems. With the rapid pace of changes in land use and climate, potential shifts in SOC quantity and quality are a major concern. Swiss soils represent the nation’s largest carbon reservoir, and hold enormous economic value. However, the vulnerability of SOC in these landscapes is not well understood.

Objectives

Using data obtained from a combination with field sampling and laboratory simulation experiments coupled with mathematical modeling studies, our objective is to investigate the distribution and fate of recent and aged SOC under warming and drought scenarios. We will use chemical and carbon isotope compositions of different soil fractions to detect changes in SOC. The utility of specific compounds and radiocarbon (¹⁴C) in different solubility and density fractions as indicators or “sentinels” of SOC vulnerability will also be assessed. To develop a broader perspective, we will acquire ¹⁴C data for over 1000 archived and contemporary soil samples, and initiate a ¹⁴C database for Swiss soils. Measurements on soils from a range of natural and managed environments as well as from laboratory simulation experiments, coupled with mathematical modeling, will enable us to better predict how SOC in Swiss soils will respond to future changes in climate and land use.

Scientific and Social Context of the Research Project

This project will produce the first comprehensive set of ¹⁴C data on a series of SOC components using compound-specific radiocarbon analysis. The ¹⁴C database, coupled with soil carbon models and mapping tools, will allow the assessment of potential SOC losses on watershed and regional scales. These results will yield new insights on soil carbon dynamics and on mechanisms controlling SOC storage, establish practical tools for assessing future function changes and for managing carbon in Swiss soils the future, and provide scientific foundation for global carbon market negotiations.

Publications

This project has resulted in several open-acces publications such as: external page Variability in14C contents of soil organic matter at the plot and regional scale across climatic and geologic gradients and external page Diverse soil carbon dynamics expressed at the molecular level. It also contribted to the recent paper on external page Relevance of carbon stocks of marine sediments for National greenhouse gas inventories of Maritime nations (external page Springer blog here)

Collaborations

Within this project, we collaborate with the University of Zurich (UZH), the Swiss Federal Institute for Forest, Snow and Landscape research (WSL) and external page Agroscope. Forest samples are taken from sites that are part of the external page Long-term Forest Ecosystem Research Programme (LWF) of the WSL.

Keywords

Radiocarbon, lignin, plant waxes, climate change, land use change, soils, soil carbon, database, compound-specific isotope analysis.

Project member

• Tessa van der Voort