The objective of this study is to quantify the activity of the deshydrogenase, ß-glucosidase and the urease in a soil with different uses and with the purpose of establishing potential measures of the chemical degradation. Four different soil uses of the same soil (Calcaric Skeletic Cambisol) were studied. Those uses were: an active olive grove (O1); an abandoned olive grove (O2); reforested pine grove (P) and natural gall-oak grove (Q). In addition of the dehydrogenase, urease and ß-glucosidase activities, the following chemical parameters: pH, electric conductivity, oxidizable organic matter, carbon organic total, total nitrogen were analysed. The quantification of the dehydrogenase and urease activities showed the same behavior pattern (r = 0.54, p < 0.01), the highest activity was found for the gall-oak grove and the minor for the active olive grove. The ß-glucosidase activity results showed that the organic matter in the abandoned olive grove had higher cellulose content than the organic matter in the others uses. If the natural fertility of the different uses is studied, we can conclude that the active olive grove was the most degraded, followed by the pine grove. On the other hand, the gall-oak grove presented the highest fertility. The high organic matter content in degradation process in the abandoned olive grove determined the highest potential fertility for this use.