Pedological formations on old mountain geomorphological surfaces of central Spain.

The chemo-morphological properties of soils on ancient landforms (quarzitic pliocene alluvial fans, pleistocene terraces), namely "rañizos", on middle-high mountains (Eastern-Central System, Iberian Peninsula, Rio Negro, Cogolludo) were investigated. Several properties were analyzed by standard procedures. A detailed soil diagnostics and classification on "rañizos" were done, unlike those widely studied on "rañas" (similar landform), by identifying parallel pedogenetic processes in both formations. The genetic and geographic features of Alfisols, Ultisols and Inceptisols are closely related to the nature of their parent materials, based on quartzite and quartz conglomerates, sometimes with an arkosic matrix, red shale, polygenic gravels and pebbles. Soil features were determined by genuine soil-forming inherent lithological rock properties. Other driving factors were flat topography and enough soil formation time to allow intense pedogenesis. The main soil-forming processes were intense weathering, clay enrichment horizons with illuviation, red color caused by iron oxide dehydration and signs of pseudogleyzation processes. Such pedological formations can be considered endemisms; that is, "rare" soils and, up to a point, "relict". The soil reaction is acid/slightly acid with low base saturation. Despite lying on mountains, soils are characterized by moderate-low organic matter content. Soil conditions and climate provide good vine production requirements despite acidity levels. A common feature of all Rio Negro soils is the presence of gravel (size up to 3-5 cm), which is evenly distributed on arable layers. The results can be used to assess vineyard soil use in a potential Pago (Protected Denomination of Origin) and to extend the database of vineyard soils from poorly studied Mediterranean continental mountain regions.

Mineralogical and Geochemical Nature of Calcareous Vineyard Soils from Alcubillas (La Mancha, Central Spain).

The mineralogical and geochemical patterns of calcareous vineyard soils located in Alcubillas (La Mancha, Central Spain) have been evaluated; also their variability has been studied. The information provided by this study supports the assessment of geochemical spatial variability, the origin of these soils, their elements and the factors that control their distribution. The presence of quartz, calcite, feldspar and, in particular, illite and kaolinite is due to their inheritance from surrounding lithologies (and pedological processes), which mostly include limestones, marls and other sedimentary rocks, as well as metasedimentary rocks of Hercynian origin. Furthermore, since the presence and accumulation of certain trace elements in vineyard soils is a relevant global hazard (in particular with respect to wine production quality), the spatial distributions of Ba, Cr, Cu, Pb, Rb, Sr, V and Zr (carried out using geostatistical techniques and geometry-based interpolation methods) were investigated in order to determine the origin of these trace elements. The presence of these elements can be interpreted as being due to geogenic, pedogenic and, in certain cases, anthropic influences. The nature of certain agricultural practices, including the use of fertilizers, phytosanitary products and machinery, could explain the local increases in some trace element contents.

Mercury transfer from soil to olive trees. A comparison of three different contaminated sites.

Mercury contents in soil and olive tree leaves have been studied in 69 plots around three different source areas of this element in Spain: Almadén (Ciudad Real), Flix (Tarragona) and Jódar (Jaén). Almadén was the world's largest cinnabar (HgS) mining district and was active until 2003, Flix is the oldest Spanish chlor-alkali plant (CAP) and has been active from 1898 to the present day and Jódar is a decommissioned CAP that was active for 14 years (1977-1991). Total mercury contents have been measured by high-frequency modulation atomic absorption spectrometry with Zeeman effect (ZAAS-HFM) in the soils and olive tree leaves from the three studied areas. The average soil contents range from 182 µg kg(-1) in Flix to 23,488 µg kg(-1) in Almadén, while the average leaf content ranges from 161 µg kg(-1) in Jódar to 1213 µg kg(-1) in Almadén. Despite the wide range of data, a relationship between soil-leaf contents has been identified: in Almadén and Jódar, multiplicative (bilogarithmic) models show significant correlations (R = 0.769 and R = 0.484, respectively). Significant correlations were not identified between soil and leaf contents in Flix. The continuous activity of the Flix CAP, which remains open today, can explain the different uptake patterns for mercury, which is mainly atmospheric in origin, in comparison to the other two sites, where activity ceased more than 10 years ago and only soil uptake patterns based on the Michaelis-Menten enzymatic model curve are observed.