02192naa a2200241 a 450000100080000000500110000800800410001902400570006010000280011724501360014526000090028152014050029065000230169565000230171865300250174165300260176670000160179270000250180870000160183370000160184970000130186577300720187821358962021-11-08 2015 bl uuuu u00u1 u #d7 ahttps://doi.org/10.1590/S1413-705420150005000012DOI1 aSILVA NETO, L. de F. da aCharacterization and classification of floodplain soils in the Porto Alegre metropolitan region, RS, Brazil.h[electronic resource] c2015 aIn the Porto Alegre metropolitan region (PAMR) there are a significant proportion of floodplain soils, mainly Planosols and Gleysols, in relation to upland soils. This study aimed to evaluate the morphological, chemical and physical characteristics, and to classify floodplain soils in the PAMR. Six soil profiles were evaluated under different sedimentary lithologies and drainage classes, and samples were collected for chemical and physical analyzes. Two orders of mineral soils (Planosols and Gleysols) and one order of organic soil (Organosols) were identified. The soils were moderately deep to deep and stratified. In mineral soils hue ranged between 7.5YR and 2.5Y, with the occurrence of Bg, Btg or Cg gley horizons, while in organic soil the colors were neutral. Sand and silt were the predominant particle sizes according to the origin sedimentary deposits. The organic carbon content was negatively related to soil density and positively related to soil specific surface area and with soil cation exchange capacity. Soil chemical characterization showed expressive variation in bases, aluminum and sodium saturation. Ki index and Fe(CBD)/Fe(H2SO4) ratio indicated a low soil weathering degree. The different sedimentary lithologies and the soil hydromorphism degree were the main factors related to differences in morphological, physical and chemical characteristics of soils in the PAMR. aHydromorphic soils aSolo Hidromórfico aQuaternary sediments aSpecific surface area1 aINDA, A. V.1 aNASCIMENTO, P. C. do1 aGIASSON, E.1 aSCHMITT, C.1 aCURI, N. tCiência e Agrotecnologiagv. 39, n. 5, p. 423-434, set./out. 2015.