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The article discusses a study which examined the spatial variability of runoff and erosion rates in vineyards of Northeastern Spain. The study examined plots with high disturbance (HD) and low disturbance (LD) of the soil profile and evaluated whether soil surface properties were conditioning runoff and erosion rates. It discusses soil and rainfall characteristics as well as runoff differences in the HD and LD plots and differences in sediment concentration.

Since the 1970s and 1980s, the vineyard areas in the Mediterranean region of north east Spain have undergone profound transformation to allow greater mechanization. This has involved land levelling, deep ploughing and the elimination of traditional soil conservation measures. Recently the EU Common Agricultural Policy encourages this through the vineyard restructuring and conversion plans (Commission Regulation EC No 1227/2000 of 31 May 2000) by subsidizing up to 50% of the cost of soil preparation such as soil movement and land levelling. A clear example of the problems that this causes is in the Penedès vineyard region (Catalonia, north east Spain), and the present research analyses the changes in soil properties caused by erosion, deep ploughing and land levelling. The study was carried out in an area of 30 000 ha for which a Soil Information System at a scale of 1:50 000 was developed based on 394 field observations (89 soil profiles and 251 auger hole samples down to 120 cm). The results show that 74% of the described soil profiles are disturbed with evidence of soil mixing and/or profile truncation due to erosion, deep ploughing and/or land levelling. The evidence from the topsoils is mainly the presence of fragments of calcic or petrocalcic horizons, marls and sandstones. Other important properties for crops such as organic matter (OM) content and soil depth show statistically significant differences between disturbed soils and undisturbed soils (22.3–33.3% OM content depletion and 35.1% soil depth reduction). These results confirm that the soils of the region are significantly altered by mechanical operations which also influence soil erosion and contribute to global warming effect through depletion of soil OM. [ABSTRACT FROM AUTHOR]

The article presents a study on the agricultural trajectories and farming systems in the Priorat region in Spain. In the Priorat region, as well as in the other mountain regions of Mediterranean European countries, the intensification of crops is said to be based on either land leveling or terracing, and the abandonment of usual land use management practices. One of the objectives of the study is to relate the coexisting farming systems in Priorat to the landscape impacts they involve. The researchers combined multivariate statistical techniques to understand the heterogeneity of farming systems on a local scale.