JWSS - Journal of Water and Soil Science

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  Many studies have been carried out on pure minerals to study the effect of plant roots on minerals weathering, but information on mineral weathering that normally occurs in different soil fractions is limited. To investigate the effect of

German Chamomile (Matricaria chamomilla L.) cultivation on mineral weathering of clay and silt fractions in five different soil series amended or not amended (control) with cattle manure, a factorial experiment was performed in a randomized complete block design (RCBD) with three replications. At harvest time, rhizosphere soil was separated and mineralogical studies were performed through X-ray diffraction (XRD) and compared to before cultivation Results showed that in clay sized particles, trioctahedral chlorite transformed to di-octahedral chlorite while kaolinite disappeared. In silt sized particles, feldspar transformed to amphibole and vice versa The pots amended with manure showed the same changes for clay and silt sized particles as the pots without manure.