Major soil classes of the metropolitan region of Curitiba (PR), Brazil: I - mineralogical characterization of the sand, silt and clay fractions

Brazilian Archives of Biology and Technology

Ana Christina Duarte Pires²  Vander De Freitas Melo¹  Valmiqui Costa Lima¹  Antônio Carlos Vargas Motta¹ 

[1] ,Universidade Federal do Paraná

关键词: Kaolinite;    crystalline and amorphous Fe and Al oxides;    2:1 minerals;    XRD;   

DOI  :  10.1590/S1516-89132007000200001

来源: SciELO

【 摘 要 】

The aim of this work was to evaluate the mineralogical and chemical characteristics of most representative soils of the Region of Curitiba, Paraná State. Samples were collected at different depths. The results showed: (a) the quartz was the only identified mineral at the silt and sand fractions. The dominant clay mineral was Kaolinite, with contents ranging from 676.7 to 820.8 g kg-1. The gibbsite was also an important constituent of the most weathered horizons and the hematite and goethite contents were low, mainly in the Histosol; (b) at the C horizon of the Inceptisol, high intensity of vermiculite/smectite reflections were detected (X-ray diffraction), justifying the high capacity of expansion and contraction, normally showed for this soil horizon; (c) was observed a good relation between pedogenetic degree and crystallographic mineral characteristics.

【 授权许可】

CC BY-NC   
 All the contents of this journal, except where otherwise noted, is licensed under a Creative Commons Attribution License