Highlights SOC stocks were modelled using legacy data, environmental factors and geostatistics. The importance of SOC stock drivers differed in the top and subsoil. Effects of drivers on agricultural SOC stocks vary spatially at the regional scale. SOC stocks in Catalan agricultural soils contain 4.88 ± 0.89 kg/m 2 .  A baseline framework was established to design climate change mitigation strategies.

In this paper, an algorithm to retrieve surface soil moisture from GNSS-R (Global Navigaton Satellite System Reflectometry) observations is presented. Surface roughness and vegetation effects are found to be the most critical ones to be corrected. On one side, the NASA SMAP (Soil Moisture Active and Passive) correction for vegetation opacity (multiplied by two to account for the descending and ascending passes) seems too high. Surface roughness effects cannot be compensated using in situ measurements, as they are not representative. An ad hoc correction for surface roughness, including the dependence with the incidence angle, and the actual reflectivity value is needed. With this correction, reasonable surface soil moisture values are obtained up to approximately a 30° incidence angle, beyond which the GNSS-R retrieved surface soil moisture spreads significantly.

The objective of this study is to analyze the influence of soil characteristics on the early growth of Quercus ilex in order to support planning of future plantations. We studied 31 200-m 2 -plots on 10-year-old plantations in fields that were set-aside from agriculture in a semiarid area in northeast Spain. Tree height and diameter, slope, geomorphic position, and various soil characteristics were measured. On north-facing slopes height and diameter of trees were significantly greater (150-200%) in soils without gypsum than in soils with gypsum. In soils without gypsum, increased penetration resistance in the upper 50 cm of soil (from 4.4 MPa to more than 7.0 MPa) decreased dominant height of trees to 40% of the maximum. While plantations of Quercus ilex can achieve satisfactory growth in semiarid conditions, detailed field studies of soil and site conditions are required for successful plantation establishment. The actual need for soil preparation treatments should be carefully evaluated considering species response and soil penetration resistance.

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