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Abstract:The knowledge of soil water content (SWC) dynamics in the upper soil layer is important for several hydrological processes. Due to the difficulty of assessing the spatial and temporal SWC dynamics in the field, some model-based approaches have been proposed during the last decade. The main objective of this work was to assess the performance of two approaches to estimate SWC in the upper soil layer under field conditions: the physically-based thermal inertia and the Hydrus model. Their validity was firstly assessed under controlled laboratory conditions. Thermal inertia was firstly validated in laboratory conditions using the transient line heat source (TLHS) method. Then, it was applied in situ to analyze the dynamics of soil thermal properties under two extreme conditions of soil-water status (well-watered and air-dry), using proximity remote-sensed data. The model performance was assessed using sensor-based measurements of soil water content acquired through frequency (FDR) and time domain reflectometry (TDR). During the laboratory experiment, the Root Mean Square Error (RMSE) was 0.02 m 3 m −3 for the Hydrus model and 0.05 m 3 m −3 for the TLHS model approach. On the other hand, during the in situ experiment, the temporal variability of SWCs simulated by the Hydrus model and the corresponding values measured by the TDR method evidenced good agreement (RMSE ranging between 0.01 and 0.005 m 3 m −3 ). Similarly, the average of the SWCs derived from the thermal diffusion model was fairly close to those estimated by Hydrus (spatially averaged RMSE ranging between 0.03 and 0.02 m 3 m −3 ).

The paper presents the activity performed at the University of Brescia by students and researchers, belonging to different Mediterranean cultures and different disciplines, to prepare a documentary exhibition on irrigation techniques in water scarcity conditions, on the occasion of the International Year of Soils 2015. Traditional irrigation techniques were identified as a key aspect of soil conservation and agricultural practices, to build living and autopoietic ecosystems, also in adverse climatic conditions, and to adapt to climatic changes. Being a structural source of ecosystem survival, and being based on long-lasting observation of the climate and of the environment, they have deep roots in local cultures and they were identified as a common ground also for multicultural interaction. The core of the exhibition is structured in sections focused on techniques for collecting groundwater, atmospheric humidity and surface water, on water lifting techniques and on water distributive systems. The final section of the exhibition is devoted to the oases which are presented as an equilibrium ecosystem, established upon the alliance between man and nature and founded on the capability of collecting water.