Multifunctionality of sheep grazing in marginal areas: a remote sensing approach in Eastern Italian Alps

Mountain pastures deliver both provisioning and non-provisioning ecosystem services. However, incorrect management may diminish their capacity to provide these positive externalities. In a pilot project aimed at restoring an abandoned alpine pasture and valorizing its biodiversity and cultural ecosystem services, this study utilized remote sensing and GPS tracking to assess the impact of sheep grazing on the pasture’s primary production. The study was conducted in the summer of 2023 in a pasture that had remained ungrazed for three years at 2000 m asl (Monte Coppolo – Eastern Italian Alps). The pasture was divided into four one-hectare sections, grazed by a flock of 30 “Lamon” local breed sheep using a rotational system with 2-week periods. GPS collars on three sheep monitored spatial use intensity, with positions recorded every two minutes. Specific spectral indexes obtained from the Copernicus SENTINEL-2 satellite mission were used to estimate the primary productivity with a pixel size of 10 m2. We used NDVI (Normalized Difference Vegetation Index), GWI (Green Way Index) and Delta NDVI (Maximum NDVI peak of 2023 – NDVI September 30, 2023). Animals’ activity was higher during daytime compared to night-time. The spatial intensity of use of the plots was uneven and showed a preference for areas with gentler slope. The combined analysis of spectral indexes and spatial intensity of use revealed vegetation regrowth patterns in intensively used areas at the end of the growing season. The results of this first year confirm that combining remote sensing and GPS tracking for monitoring alpine pastures could represent a valid contribution to analyzing the positive outcomes derived from these agroecosystems.