This study aimed to evaluate the relationship between the mineralogical constituents of clay fraction and the development of micro and macrostructure of Latosols (Oxisols) from southeastern Brazil. For that purpose, samples of oxic horizons were obtained from seven Latosols representative of this group, from Minas Gerais and Espírito Santo states. The different soil samples were submitted to morphological, chemical, physical, mineralogical and micromorphological characterizations. From the different results it was possible to conclude that kaolinite and gibbsite are the main mineralogical constituents responsible for the structure development of the studied Latosols. Kaolinitic Latosols present blocklike structure, reflex of face to face adjustment of kaolinite plates, while the gibbsitic ones present granular structure, resulting from the absence of that adjustment.
kaolinite; gibbsite; aggregation; soil micromorphology