The site consists of “orographic islands” with high elevation vegetation in central Mediterranean basin, along the Apennines mountain range, within the Appennino Tosco-Emiliano National park and partially in the Appennino Modenese Regional park. It includes 64 permanent plots for plant species monitoring, distributed from timberline zone to the subalpine/alpine belt (1722-2000 m), that belong to the GLORIA project’s world network (GLobal Observation Research Initiative in Alpine ecosystems); The plots lie at the top of four summits, displayed along an altitudinal gradient, chosen following the GLORIA Target Region selection criteria. Furthermore, other 26 permanent plots, detached from the GLORIA project, have been settled on mount Prado. The observation and the long-term monitoring of vegetation and alpine plant species population started in 1999. The collection of soil temperature and osmotic potential started in 2001 and 2013, respectively. The site is resurveyed regularly to collect vegetation data (in term of presence/absence and coverage) and climatic data (temperature and osmotic potential data series recorded every 30 minutes by data loggers) in order to assess impacts of climate change on plant communities and single plant species of interest.

The site, located along the Tyrrhenian coast, north of Rome city, is a Special Protection Area (SPA) for migratory and nesting birds (Anatidae, Ardeidae). The wetland area is one of the last stretches of the Lazio wetlands which have been progressively reclaimed and cultivated during the last century. The flora and the fauna of the site is not only highly specialized but also highly endangered, with a relevant ecological value evidenced in previous studies. The site includes coastal dune habitats of European interest, as the annual vegetation of drift lines, the embryonic shifting dunes, the mobile dunes with Ammophila arenaria and the dune grasslands. There are also habitats related to wet and mud soils, as Mediterranean salt meadows and reed beds dominated by Phragmites australis.

The Hölstein site is located in in the eastern part of the Swiss Jura mountains (47°26’16.4’’, 7°46’31.1’’; 540 m a.s.l.), in a mixed, temperate forest with an exceptionally high biodiversity and a vigorous tree regeneration. The research plot has a size of 1.6 ha and comprises 540 mature trees. The main tree species are Fagus sylvatica and Picea abies with an admixture of Abies alba, Quercus petraea, Pinus sylvestris, Acer pseudoplatanus, Carpinus betulus, Fraxinus excelsior and Sorbus torminalis. A canopy crane is installed in the center of the research area to access the tree canopies for in situ measurements and for sampling of leaf material. Rainout shelters will be installed in 2019 for conducting a long-term throughfall exclusion experiment.

As the largest contiguous pine forest in Switzerland, the Pfyn forest in Canton Valais (46° 18' N, 7° 36' E, 615 m ASL) offers the best conditions for such measurements. In light of this, a WSL research team installed a long-term experiment of 20 years duration in the Pfyn forest. The average temperature here is 9.2°C, the yearly accumulated precipitation is 657 mm (average 1961-1990). The pines in the middle of the forest are about 100 years old and 10.8 m high. The test area has 876 trees covering 1.2 ha divided into 8 plots of 1'000 m2 each (Image 4). Between the months of April and October four of these plots are irrigated by a sprinkler system providing an additional 700 mm of water, annually. In the other four plots, the trees grow under natural, hence relatively dry conditions.

Mountain site, alpine forests Sierra Nevada (Andalusia, SE Spain), is a mountainous region with an altitudinal range between 860 m and 3482 m a.s.l. covering more than 2000 km2. The climate is Mediterranean, characterized by cold winters and hot summers, with pronounced summer drought (July-August). The annual average temperature decreases in altitude from 12-16ºC below 1500 m to 0ºC above 3000 m a.s.l., and the annual average precipitation is about 600 mm. Additionally, the complex orography of the mountains causes strong climatic contrasts between the sunny, dry south-facing slopes and the shaded, wetter north-facing slopes. Annual precipitation ranges from less than 250 mm in the lowest parts of the mountain range to more than 700 mm in the summit areas. Winter precipitation is mainly in the form of snow above 2000 m of altitude. The Sierra Nevada mountain range hosts a high number of endemic plant species (c. 80; Lorite et al. 2007) for a total of 2,100 species of vascular plants (25% and 20% of Spanish and European flora, respectively), being considered one of the most important biodiversity hotspots in the Mediterranean region. This mountain range has several legal protections: Biosphere Reserve MAB Committee UNESCO; Special Protection Area and Site of Community Importance (Natura 2000 network); and National Park. The area includes 61 municipalities with more than 90,000 inhabitants. The main economic activities are agriculture, tourism, cattle raising, beekeeping, mining, and skiing.