TY - JOUR
T1 - Chemical and spectroscopic characterization of humic acids extracted from the bottom sediments of a Brazilian subtropical microbasin
AU - Giovanela, M.
AU - Crespo, J. S.
AU - Antunes, M.
AU - Adamatti, D. S.
AU - Fernandes, A. N.
AU - Barison, A.
AU - Da Silva, C. W.P.
AU - Guégan, R.
AU - Motelica-Heino, M.
AU - Sierra, M. M.D.
PY - 2010/9/24
Y1 - 2010/9/24
N2 - Humic substances (HS) perform a fundamental role in aquatic environments, exhibiting different levels of reactivity in retaining metal ions and organic pollutants. Also, they control the primary production of these ecosystems and act in the carbon sequestering process. In order to improve our understanding vis - vis the structural and functional features of HS from aquatic systems, this study aimed to chemically and spectroscopically characterize humic acids (HA) isolated from bottom sediment samples of a stream in a Brazilian subtropical microbasin by elemental analysis, and infrared (FT-IR), ultraviolet and visible (UV-Vis) and solid-state 13C nuclear magnetic resonance (CP-MAS 13C NMR) spectroscopies, thermogravimetry (TG), and scanning electron microscopy (SEM). Although all samples originated from the same environment, the data showed that the HA have distinct chemical and spectroscopic properties, and that the location and characteristics of the sampling points from which the sediments were collected played an important role in the differences observed. Furthermore, vascular plant matter is probably the main contributor to these samples.
AB - Humic substances (HS) perform a fundamental role in aquatic environments, exhibiting different levels of reactivity in retaining metal ions and organic pollutants. Also, they control the primary production of these ecosystems and act in the carbon sequestering process. In order to improve our understanding vis - vis the structural and functional features of HS from aquatic systems, this study aimed to chemically and spectroscopically characterize humic acids (HA) isolated from bottom sediment samples of a stream in a Brazilian subtropical microbasin by elemental analysis, and infrared (FT-IR), ultraviolet and visible (UV-Vis) and solid-state 13C nuclear magnetic resonance (CP-MAS 13C NMR) spectroscopies, thermogravimetry (TG), and scanning electron microscopy (SEM). Although all samples originated from the same environment, the data showed that the HA have distinct chemical and spectroscopic properties, and that the location and characteristics of the sampling points from which the sediments were collected played an important role in the differences observed. Furthermore, vascular plant matter is probably the main contributor to these samples.
KW - Elemental analysis
KW - Humic acids
KW - Scanning electron microscopy
KW - Spectroscopy
KW - Subtropical microbasin
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UR - http://www.scopus.com/inward/citedby.url?scp=77956344024&partnerID=8YFLogxK
U2 - 10.1016/j.molstruc.2010.07.038
DO - 10.1016/j.molstruc.2010.07.038
M3 - Article
AN - SCOPUS:77956344024
VL - 981
SP - 111
EP - 119
JO - Journal of Molecular Structure
JF - Journal of Molecular Structure
SN - 0022-2860
IS - 1-3
ER -