Guest Blog

I met Meritxell and Laia one bright sunny day in April, in the Pallars Sobirà, a mountainous county in the Catalan Pyrenees. Both are women farmers and work in livestock management – Meritxell is a cattle rancher, while Laia herds goats and makes cheese.  Unlike most women in the region, both have made a conscious choice to live and work in the Pallars’ hills, despite the harsh conditions. Even as spring unfolds, from their houses they can watch the flakes of snow still covering the mountain pastures. Soon the foothills are slowly revealed, uncovering green meadows and flowers, with bees popping out from the white winter coating. Catalunya Pallars Sobirà. Wikimedia, CC BY-NDI met Meritxell and Laia through the AGATA research project on the social and agricultural dynamics in the Pallars Sobirà region. I am trying with my colleagues to understand the threats to agricultural and pastoral systems in mountainous areas, including environmental and...

Background [caption id="attachment_2340" align="alignleft" width="300"] Figure 1. Entomologists sampling stands of Norway spruce dieback in the Bavarian Forest National Park, Germany. Photo: Heiner M.-Elsner.Mountain forests play a major role in the preservation of biodiversity and provide important ecosystem services such as climate regulation. However, some of these forests show extensive tree mortality (“forest diebacks”) caused by a combination of factors, such as severe and recurrent summer drought, pollution, and insect and pathogen outbreaks. Some of the most spectacular cases of forest diebacks are caused by bark beetle outbreaks, which have killed millions of hectares of conifer forests worldwide (Fig. 1).Forest diebacks are expected to become more widespread, frequent and severe. Indeed, warm and dry climate conditions increase the number of bark beetle generations per year and decrease tree vigor. Diebacks are accompanied by changes in tree species composition, which can happen either by natural regeneration or by artificial replacement with better-adapted...