02135naa a2200253 a 450000100080000000500110000800800410001902200140006002400520007410000220012624501570014826000090030530000110031452013390032565300230166465300230168765300200171070000200173070000180175070000180176870000220178670000210180877300520182921346322022-06-10       2021    bl uuuu     u00u1 u    #d  a1866-62997 ahttps://doi.org/10.1007/s12665-021-09697-12DOI1 aHUAMÁN, J. L. C.  aCharacterization and distribution of mineral phases in an Amazonian humiluvic Spodosol profile by XRPD, HR-TEM, SAED and SEM-EDX.h[electronic resource]  c2021  a1 - 11  aThe Amazonian biome has a fundamental role in the global climate change scenario and the understanding the physicochemical aspect in Amazonian soils is of great importance. The nine horizons constituting a typical Amazonian Spodosol profle were studied by diferent complementary techniques: X-ray powder difraction (XRPD), high-resolution transmission electron microscopy (HR-TEM), selected area electron difraction (SAED) and scanning electron microscopy-energy-dispersive X-ray spectrometry (SEM–EDX). The XRPD analysis revealed the presence of diferent minerals along the profle, i.e. quartz from 0 to 214 cm (horizons from A1 to Bhs) and kaolinite from 215 to 290 cm (horizons from Tr to K2). The HR-TEM images and SAED patterns revealed the presence of kaolinite in the horizon A1, which was not detected by XRPD. Application of the Rietveld refnement enabled the quantifcation of the minerals in each horizon. The SEM–EDX analyses allowed to identifying changes in the horizon surface morphology as a consequence of ongoing deformation. A signifcant decrease of particle sizes and a marked variations of their surface features with increasing depth were measured by SEM. In conclusion, the results of this work provide new insights into the relationship between chemical properties and mineral changes along the soil profle.  aAmazonian Spodosol  aHorizons structure  aRietveld method1 aNICOLODELLI, G.1 aSENESI, G. S.1 aMONTES, C. R.1 aPERRUCI, N. A. F.1 aBEZZON, V. D. N.  tEnvironmental Earth Sciencesgv. 80, 405, 2021.