FN Archimer Export Format
PT J
TI Distribution, speciation and composition of humic substances in a macro-tidal temperate estuary
BT 
AF Riso, Ricardo
   Mastin, Manon
   Aschehoug, Arthur
   Davy, Romain
   Devesa, Jeremy
   LAES HUON, Agathe
   Waeles, Mathieu
   Dulaquais, Gabriel
AS 1:1;2:2;3:1;4:2;5:1;6:2;7:1;8:2;
FF 1:;2:;3:;4:PDG-REM-RDT-LDCM;5:;6:PDG-REM-RDT-LDCM;7:;8:;
C1 Laboratoire des Sciences de l'environnement Marin, Institut Universitaire Européen de la Mer, CNRS/IRD/UBO/IFREMER (UMR 6539), Place Nicolas Copernic, F-29280, Plouzané, France
   Laboratoire Détection Capteurs et Mesures, Unité de Recherches et Développements Technologiques, Ifremer, France
C2 UBO, FRANCE
   IFREMER, FRANCE
SI BREST
SE PDG-REM-RDT-LDCM
UM LEMAR
IN WOS Ifremer UPR
   WOS Cotutelle UMR
   copubli-france
   copubli-univ-france
IF 3.229
TC 9
UR https://archimer.ifremer.fr/doc/00688/80019/83004.pdf
LA English
DT Article
DE ;Humic substances;Estuary;Suspended particulate matter;Biogeochemistry
AB In aquatic environments, the term humic substances (HS) encompasses terrestrial and autochthonous refractory organic matter. HS are one of the main fractions of natural organic matter and are important chelators of trace elements. In environmental studies, the determination of HS is often restricted to the dissolved fraction, and the content of HS in the suspended particles remains unknown. In this work, we present the composition and dynamics of HS along the mixing gradient of a macrotidal estuary in both the dissolved and particulate fraction. After the isolation of particulate HS using a solid-liquid alkali extraction method, HS were characterized by size exclusion chromatography (SEC) and electrochemical methods. The method, validated using a certified reference material, demonstrated a low detection limit (μg-C L−1), a good repeatability (7.7%) an excellent reproducibility (1.3%) and was poorly prone to contamination (filter blank < 1 μg-C). Analyses of environmental samples showed a particulate fraction contributing significantly to the total humic pool in the estuary (3–20%) and representing up to 35% of electroactive HS. Phase transfers from the dissolved to the particulate fraction were observed and the electroactive HS were strongly affected in the maximum turbidity zone. Multi-detection SEC analyses showed differences in the molecular composition between the dissolved and particulate fractions. Particulate HS were more nitrogen-rich and electroactive than dissolved HS. The non-conservative changes in the composition of HS along the land-sea continuum evidence the existence of abiotic and biotic processes that altered HS during their transit from river to marine waters. 
PY 2021
PD JUN
SO Estuarine Coastal And Shelf Science
SN 0272-7714
PU Elsevier BV
VL 255
UT 000653045800009
DI 10.1016/j.ecss.2021.107360
ID 80019
ER

EF