Fractionation of lignin during leaching and sorption and implications for organic matter “freshness”

1024 681 Stroud Water Research Center

Hernes, P.J., A.C. Robinson, and A.K. Aufdenkampe. 2007. Geophysical Research Letters 34:L17401.



Much of what we know about the cycling of terrigenous organic matter (OM) in freshwater and marine systems can be attributed to evidence derived from biomarkers such as lignin. Here we report the fractionation of lignin phenols both during solubilization from plant litters and again during sorption of resulting leachates to soils. Source parameters in both leached and sorbed lignin varied from the parent litters by as much as ten-fold, while elevated lignin oxidation parameters in riverine dissolved OM (DOM) can be completely explained by dissolution and sorption. Carbon-normalized dissolved lignin endmembers indicate a substantial fraction of riverine DOM may not be vascular plant-derived, and thus derived from algal, microbial or non-vascular plant sources such as mosses. These results demonstrate that riverine DOM is less degraded and likely more labile than previously thought, and helps resolve the paradox of diagenetically-altered riverine DOM degrading rapidly in marine systems.

Give the Gift of Fresh Water

As you give thanks for the gifts in your life, we invite you to give the gift of water. Clean drinking water, good health, happy trout, productive soil, clean air, the simple joys of swimming, boating, fishing — our healthy freshwater ecosystems make these and so many other things possible.

Your donation today will help preserve and protect
the future of fresh water.