In Mediterranean oak-savannas (known as Dehesas in Spain), it is vital to understand the interactions between vegetation structure and local climate regulation at scales relevant to farm management and the dominant hydrological regime. We evaluated the water use patterns of dehesa vegetation patches (open grasslands, lowland grasslands with high soil moisture, tree + grass, and riparian vegetation) to analyze the spatial and temporal resolution needed for the different management levels.

Drought is a devastating natural hazard and difficult to define, detect and quantify. Global meteorological data and remote-sensing products present new opportunities to characterize drought in an objective way. In this paper, we applied the surface energy balance model SEBS to estimate monthly evapotranspiration (ET) from 2001 to 2018 over the dehesa area of the Iberian Peninsula. ET anomalies were used to identify the main drought events and analyze their impacts on dehesa vegetation.

To obtain magnitudes of flux components of H₂O and CO₂ (e.g., transpiration, soil respiration), we applied source partitioning approaches after Scanlon and Kustas (2010) and after Thomas et al. (2008) to high-frequency eddy covariance measurements of 12 study sites covering various ecosystems (croplands, grasslands, and forests) in different climatic regions. We analyzed the interrelations among turbulence, site characteristics, and the performance of both partitioning methods.

This work investigates the effect of different parameterizations to account for water stress on GPP estimates and their agreement with observations. GPP is estimated with a LUE-model in the footprint of the EC tower using several approaches. The preliminary results obtained during two hydrological years (2015/2016 and 2016/2017) are compared, focusing on specific wet and dry periods.