Early diagenesis of lignin-associated phenolics in the salt marsh grass Spartina alterniflora

Journal Article · Thu Oct 01 04:00:00 EDT 1992 · Geochimica et Cosmochimica Acta; (United States)

DOI:https://doi.org/10.1016/0016-7037(92)90168-I· OSTI ID:7159387

Haddad, R I; Martens, C S ^[1]; Newell, S Y ^[2]; Fallon, R D ^[3]

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1. Univ. of North Carolina, Chapel Hill (United States)
2. Univ. of Georgia Marine Inst., Sapelo Island (United States)
3. DuPont Co., Wilmington, DE (United States)

The predepositional stability of lignin in the salt marsh cordgrass Spartina alterniflora was examined in two different degradation studies: one was a traditional litterbag study carried out using post-senescent brown leaves in a North Carolina marsh creek, and the other was a study in which senescing, standing plants were tagged and allowed to undergo in situ degradation in a Sapelo Island, Georgia, salt marsh. Based on results from lignin oxidation product (LOP) analysis of leaves, lignin in the S. alterniflora was shown to be significantly degraded in both studies, with 13 [plus minus] 2% and 25 [plus minus] 12% of the total lignin mass loss occurring over the 496-day litterbag and 146-day tagged studies, respectively. A comparison of the results from both studies suggests that most of the calculated lignin loss (> 90%) occurs early in the degradation history of the plant, with a significant portion occurring while the plant is still standing in the salt marsh. Further detailed evaluation of this loss demonstrates that selective lignin degradation occurs in S. alterniflora, deriving from the preferential loss of labile lignin moieties. Based on measured changes in both the lignin mass loss and the LOP acid/aldehyde ratio, as well as evidence suggesting that degradation occurred under oxic conditions, it is proposed that aromatic ring cleavage was the predominant mechanism of lignin degradation in both studies. In light of these results and those from other recent lignin degradation studies, the authors discuss the geochemical consequences regarding the usefulness of lignin oxidation products as quantitative tracers of vascular plant-derived organic matter being transported, deposited, and buried in aquatic environments.

• OSTI ID: 7159387
• Journal Information: Geochimica et Cosmochimica Acta; (United States), Journal Name: Geochimica et Cosmochimica Acta; (United States) Vol. 56:10; ISSN GCACAK; ISSN 0016-7037
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
580000* -- Geosciences
AQUATIC ECOSYSTEMS
AROMATICS
BIOCHEMISTRY
BIODEGRADATION
CARBOHYDRATES
CHEMICAL COMPOSITION
CHEMICAL REACTIONS
CHEMISTRY
DECOMPOSITION
DELIGNIFICATION
DEPOSITION
DIAGENESIS
ECOSYSTEMS
GEOCHEMISTRY
GRAMINEAE
HYDROXY COMPOUNDS
LIGNIN
LILIOPSIDA
MAGNOLIOPHYTA
MARSHES
ORGANIC COMPOUNDS
OXIDATION
PHENOLS
PLANTS
POLYSACCHARIDES
REEDS
SACCHARIDES
SEDIMENTS
THERMODYNAMIC ACTIVITY
WETLANDS