Changes in traditional farming have led to forest expansion in the Pyrenees
This is shown by a recent paper that examines how the treeline position has changed in the Pyrenees in the last 50 years. According to the study, the treeline has advanced 40 meters on average, and the decrease in livestock pressure is one of the main causes. Contrary to the belief so far, climate change would play a much less important role. Complete note here.