Disruption of traditional land use regimes causes an economic loss of provisioning services in high-mountain grasslands

Mountain ecosystems face many challenges related to global change. Most high-altitude grasslands in the Pyrenees, despite representing valuable assets recognised in the European conservation heritage, are at risk due to the decline of traditional extensive ranging. This research intends to quantify economically the loss of the provisioning service of high-quality food for livestock of an upland area on the western side of the range. The area is experiencing degradation due to the expansion of the native tall-grass Brachypodium rupestre, favoured by disruption of traditional grazing and anthropogenic fire regimes. We implement the substitution economic approach and use floristic and husbandry data to determine that the loss of food rations for livestock results in an unitary cost of 107 €.ha−1.year−1, amounting to 21146 € for the whole degraded area, according to the most conservative estimate. The study also finds evidence that the decline in grassland value is closely associated with the digestibility to herbivores of B. rupestre during the growing season. This approach may be an effective tool to raise awareness of the problem among local and regional stakeholders and encourage further environmental actions to prevent the degradation.