Open AccessMicrobial transformation of labile dissolved organic matter into humic‐like matter in seawater
Author(s) -
Tranvik Lars J.
Publication year - 1993
Publication title -
fems microbiology ecology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.377
H-Index - 155
eISSN - 1574-6941
pISSN - 0168-6496
DOI - 10.1111/j.1574-6941.1993.tb00030.x
Subject(s) - dissolved organic carbon , seawater , organic matter , environmental chemistry , particulates , humic acid , adsorption , fraction (chemistry) , chemistry , biology , chromatography , organic chemistry , ecology , fertilizer
Microbial transformation of labile, low molecular weight dissolved organic matter (DOM) into dissolved humic matter (DHM) was studied in seawater. Surface water samples were amended with [ 14 C into 14 CO 2 , TO 14 C (total organic 14 C), and PO 14 C (particulate organic 14 C), was measured over time in confined samples. The humic and non‐humic fractions of DO 14 C (dissolved organic 14 C) were separated according to a common operational definition of DHM based on adsorption on XAD‐8 macroporous resin. Both TO 14 C and non‐humic DO 14 C decreased during the experiments. However, 14 C‐labelled DHM increased during the first week of the incubations, to a level where it comprised 15% of the TO 14 C remaining in the samples, or 3% of the initially added 14 C. Towards the end of experiments (ca 70 days), the humic fraction of DO 14 C gradually approached the background level of poisoned control samples. Provided that the XAD‐8 operational definition of DHM is accepted, this study indicates that humic matter may be formed in seawater within days from labile monomers such as glucose.