Humic substances in podzolized pedo-landscape in the Upper Negro River, Brazil : characterization of fulvic and humic acids in soil and distribution complexing capacity with metal ; Les différences entre les Podzols épais hydromorphiques et les cryptopodzols du bassin du Rio Negro (Amazonie, Brésil) étude de la caractérisation de la matière organique par spectroscopie : étude de la caractérisation de la matière organique par spectroscopie ; Estudo das substâncias húmicas em pedo-paisagem podzolizada na bacia do Alto Rio Negro- AM, Brasil

The purpose of this study is understaning the behavior of fulvic and humic acid fractions in a podzolized soilssystem, taking into account soils characteristics and to investigate the complexing capacity of Cu + 2 and Al + 3.For this purpose, conventional pedology and spectroscopic methods, Uv-Visible absorbance Spectroscopy, FourierTransform Infrared Spectrometry (FTIR) and Quenching Fluorescence using the CP/PARAFAC treatment wereused to achieve the objectives: (i) to determine the stages of transformation of the pedo-landscape through thestudy of soils and the spatial distribution of podzolized soils and gleysol in a drainage basin; (ii) to characterize SHand to understand the distribution patterns of fulvic and humic acids in a podzolized soil sequence along a slopeand in the horizons along the soil profiles taking into account the morphological characteristics, texture, pH, carbontotal and groundwater variation in the horizons of the soils of a sequence of podzols soils; (iii) to study thecomplexing capacity of humic substances (fulvic and humic acids) of podium soils samples in the Alto Rio NegroBasin, by identifying the fluorescent components of humic substances, evaluating capacities and complexingconstants of these substances with the Cu + 2 and Al + 3 metals, and the comparison with the functional groupsobtained with FTIR. Although fulvic acids are more aromatic and condensed their character is predominantlyaliphatic and hydrophilic and secondarily aromatic and carboxylic. Humic acids are less aromatic and lesscondensed than fulvic acids and are characterized by polysaccharide and ether/alcohol functions, but secondarilytheir character is aliphatic and hydrophilic. These differences are related to the presence of the functional groupsthat are responsible for the differences in the complexation dynamics of the metals, in the humic acids complexesCu+ 2 and Al+ 3 are associated with the functional groups ether/alcohol and CO polysaccharides while in the fulvicacids the correlation is greatest with the ...