Estudio de los fosfatos inorgánicos en relación con el grado de evolución en andosoles

Abstract

The relationship of the several fractions of the inorganic phosphates, extracted by the Chang-Jackson method, with the weathering degree of the Canary Islands andosols show the following trend: 1. The fractions P-Ca and P-Al decrease as the weathering degree increase, giving the aluminium phosphate a maximum in the Evolued Vitrandepts. 2. The fraction P-Fe has not very much variation in the sequence, excluding the profil Manantiales, which has a very high values comparably to the other profiles. 3. The P-occluded tends to increase with the weathering degree. Chang-Jackson's hypothesis goes quite well to these soils, beacuse the differents forms of soil inorganic phosphates are related with the weathering degree according to the following tendence: P-Ca, P-Al, P-Fe, P-occluded.