Study Areas
The FLUχPEC study site is a grazed dehesa located in Majadas del Tietar (Cáceres) in the north-east of Extremadura region (figure 2). Extremadura (Central-Western Spain) represents the primary area for oak forests in Spain with 15590 km2, where oak forests and woodlands dominate (Plieninger et al. 2010). According to their climate, Majadas could be classified as a Typical Dehesa (Sánchez de Ron et al., 2007), located in relatively wet areas, with mean annual precipitations over 500 mm (592 mm), a markedly dry summer period and mean annual temperatures over of 14 ºC (16.6ºC). The structure of the dehesa is characterized by a mean tree cover of 20 % with an average tree diameter of 45.4 cm and a diameter distribution very similar to the middle age dehesas (150-250 years) described by Plieninger et al (2003) in a nearby region of Caceres, where the most frequently diameter classes are between 40-50 cm. The mean tree density in Majadas of 25 trees/Ha represents an intermediate value for the usual tree density range for the dehesas in Spain of 15-45 trees/Ha (Pulido and Picardo 2010). Dehesas soils are usually characterized by their low fertility (Olea and San Miguel-Ayanz 2006). The soils at the Majadas site match this profile, being acidic poorly drained stagnic alisols over arkose with low organic matter contents. The pasture layer is composed mainly by grasslands, has an annual yield production and species composition very dynamic and strongly dependent on the yearly water availability with the maximum biomass production in spring followed by a second maximum in the late autumn.
Meteorological daily data for Majadas area are available at AEMET (Agencia Estatal de Meteorología).
Near real time data is available through the IMECC Terrestrial Carbon Data Center, which provides highly standardized and quality controlled carbon, water and energy fluxes measurements from eddy covariance sites. Majadas area counts on daily images from a webcam located on the flux tower.