My research has mainly been on vegetation changes in the Siberian Arctic tundra landscape. We have a long-running field experiment (2007-2019) which showed how vulnerable the Arctic tundra ecosystem is. The main result of our research is that disturbance of the tundra vegetation can result in a collapse of the ecosystem. This has consequences for the greenhouse gas balance. However, some recovery of the tundra vegetation can take place, but it is unknown how long this will take.