Comparison of extractable soil carbon and dissolved organic carbon by their molecular characteristics

0369017 - BC 2012 RIV CZ eng J - Journal Article
Šestauberová, Martina - Novák, František
Comparison of extractable soil carbon and dissolved organic carbon by their molecular characteristics.
Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis. Roč. 59, č. 6 (2011), 337-342. ISSN 1211-8516. E-ISSN 2464-8310
Grant - others:Evropská unie(XE) 100018967 Cíl 3 - ČR-Sasko
Institutional research plan: CEZ:AV0Z60660521
Keywords : DOC * humic substances * molecular weight
Subject RIV: EH - Ecology, Behaviour

The aim of this study was to compare the molecular characteristics of extractable soil carbon from biotopes of the Rašeliník watershed and dissolved organic carbon (DOC) from Rašeliník creek, by using the 0.1 M pyrophospate, 0.01 M CaCl₂ and Britton-Robinson buffer as extraction agents. The molecular weight M_r and weight-average molecular wight M_w determined by the low pressure size exclusion chromatography. Elution curves of all humic substances were characteristic by two peaks with predominant low-molecular fraction. M_r and M_w values of aquatic humic substances were 5.9 and 7.9 kDa, respectively, and proportion of this low-molecular fraction reached 97%. This corresponds to the fact, that the main fraction of HS in surface waters constitute fulvic acids. Using soil extraction in CaCl₂ we obtained the fraction of organic carbon similar to the humic substances contain in DOC.
Permanent Link: http://hdl.handle.net/11104/0203190