Arctic soils are both a source and sink of atmospheric carbon. Winter and snow regulate the functioning of Arctic ecosystems, including carbon cycling. Climate change is expected to change snow cover in Finland and affect most strongly the northernmost areas. In this project, we investigate how winter regulates microbes that are able to fix atmospheric carbon into Arctic soil either using light or without light. We use modern genomic tools and stable isotope labeling to identify and quantify which carbon fixation pathways are active in Arctic soil biocrusts. To ecologically link field and laboratory data, we use drone-based remote sensing to map biological soil crusts and snow depth. We create predictions on how carbon cycling in Arctic soil responds to changing winters with climate warming. The results elucidate how eroded or damaged Arctic soils may recover their function as carbon sinks.

2023

2026