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The main objective is to analyse the soil physical degradation in a test-site in Castilla-La Mancha (Spain). The test-site is located in a semi-arid zone, where the rainfall is scarce, lower than 400 mm, and not well distributed throughout the crop cycles, with a strong Mediterranean character. Moreover, the reference evapotranspiration is elevated (higher than 1,000 mm year(-1)). So, irrigation is very common in this zone. The implementation of irrigation in the zone began 30 years ago.

Soils of six irrigation plots were analyzed. In these plots there was a crop rotation: maize,barley, wheat, potato and sugar beet. These plots belong to a commercial farm. They have been continuously irrigated for twenty-five years. These soils are characterized by thin epipedons, with low organic matter content, and subsurface horizons with carbonate accumulation. On these plots an index of physical degradation of soil was calculated based on: crust index, structural stability and water holding capacity. In every case the values obtained were lower than 0.033. These values mean a low or reduced level of physical degradation. The physical degradation obtained for irrigation soils is lower than the one for non-irrigation soils, in this zone. Since, the results show that the irrigation does not cause physical degradation, control and reclamation measures for these soils are not necessary.