Variations in the composition and adsorption behavior of dissolved organic matter at a small, forested watershed

Changes in dissolved organic matter quality in a peatland and forest headwater stream as a function of seasonality and hydrologic conditions

“…This can be explained by a higher contribution of shallow groundwater and decreasing discharge through the peaty surface layers of the riparian zone. Due to the adsorption of larger, more aromatic compounds to mineral phases, groundwater DOM is typically of smaller molecular size and less aromatic (Meier et al, 2004;Inamdar et al, 2012). For the bog site, increasing C1 % and bog-derived humic-like C4 %, as well as decreasing molecular size, also hints at a DOM source change toward deeper peat layers.…”

“…Organic soil layer DOM can be highly aromatic or humic, reflecting decomposition of complex plant and soil organic matter. As DOM percolates through the soil, sorption to mineral phases preferentially removes larger, aromatic components (e.g., Meier et al, 2004;Kaiser and Zech, 2000), and longer residence times enhance alteration of DOM by microbial processes. Thus groundwater DOM is mostly of microbial origin and of apparently smaller molecular size (e.g., Inamdar et al, 2012;Singh et al, 2014).…”

Dissolved organic carbon dynamics in a UK podzolic moorland catchment: linking storm hydrochemistry, flow path analysis and sorption experiments

“…However, even with only small contributions of organo-mineral soils in catchments, DOC concentrations strongly increase with increasing flow (as in the present study). example Hinton et al, 1998;Meier et al, 2004), although most document forested ecosystems. It is generally recognised that surface organic horizons contribute large amounts of DOC as a by-product of microbial decomposition.…”

“…Groundwater should be most depleted in DOC, especially aromatic and high molecular weight forms due to extended contact times with sorbing subsoils (Meier et al, 2004). However, groundwaters may mix with DOCenriched waters when passing through riparian soils that act as DOC stores (Hagedorn et al, 2000).…”

“…There have been widespread and numerous reports of, and attempts to explain, increasing (and sometimes decreasing) DOC concentrations in surface waters in the US, Canada and Europe (Worrall et al, 2004;Skelkvåle et al, 2005;Monteith et al, 2007). In a recent paper Morel et al (2009) give three main reasons why examining the delivery of DOC to streams from their catchments during storm events is a critical part of furthering these explanations: (i) that the majority of DOC is exported during storm events, (ii) that event-duration (i.e.…”