+ Resolve Article
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter

+ Translate
+ Subscribe to Site Feed
GeoScience Most Shared ContentMost Shared Content

Influence of Spartina and Juncus on saltmarsh sediments; III, Organic geochemistry

, : Influence of Spartina and Juncus on saltmarsh sediments; III, Organic geochemistry. Chemical Geology 255.1-2

Total organic carbon, C/N ratios of sediment organic matter and delta13 C of sediment organic matter (delta13 C(org) ) were measured as a function of depth at four sites in a saltmarsh on Sapelo Island, GA during summer 2006. The goal of this study is to assess the sources of sediment organic matter at each site and to investigate the influence of macrophytes and macrofauna on the observed carbon isotopic signatures and C/N ratios at each site. The four sites include two adjacent creekside sites, one densely vegetated by tall-form Spartina alterniflora and the other mostly unvegetated, together with two adjacent sites higher in the marsh, including a site with sparse short-form Spartina and a neighboring site densely vegetated with Juncus roemarianus. Total organic carbon in the sediments of these sites varies between 2.1 and 6.4%, with the highest values observed at shallow depths at the unvegetated creek bank and the lowest at the short Spartina site. C/N ratios of the sediment organic matter vary between 10.6 and 17.3, with higher values at the short Spartina site compared to the other three sites. delta13 C(org) varies little with depth, averaging -20.1 + or - 0.2 ppm at the Juncus, tall Spartina and adjacent unvegetated sites, and -17.8 + or - 0.6 ppm at the short Spartina site. Mixing calculations completed with the depth-averaged C/N and delta13 C(org) for each site, assuming three endmember organic matter sources (C3 plants, C4 plants, phytoplankton), suggest that up to 75% of the organic matter at all four sites is derived from phytoplankton. Surprisingly, the average delta13 C(org) and C/N values, and therefore the calculated contributions of the three endmember organic matter sources to the total sediment organic matter, are very similar at the Juncus, tall Spartina and unvegetated creekbank sites. The greater delta13 C(org) and C/N of the short Spartina sediments is consistent with little or no inclusion of C3 -derived organic matter in the sediments at this site, in spite of the close proximity to the densely-vegetated Juncus site, and with less degradation of the organic matter compared to the other three sites.


DOI: 10.1016/j.chemgeo.2008.06.015

Other references

French, R.B., 1972: Rural medicine: cancer. Journal of the Maine Medical Association 63(11): 245-248

Blot, P., 1981: Postoperation resuscitation and monitoring of the recovery period. Soins; la Revue de Reference Infirmiere 26(3): 49-54

Steegmaier, M.; Borges, E.; Berger, J.; Schwarz, H.; Vestweber, D., 1997: The E-selectin-ligand ESL-1 is located in the Golgi as well as on microvilli on the cell surface. Neutrophils and subsets of lymphocytes bind to E-selectin, a cytokine inducible adhesion molecule on endothelial cells. The E-selectin-ligand-1 (ESL-1) is a high affinity glycoprotein ligand which participates in the binding of mouse myeloid cells...

Hashemi, H.; Taherzadeh, M.; Khabazkhoob, M., 2014: Correction of high myopia with foldable Artiflex Phakic intraocular lenses: 1 year follow-up results. To assess the one year results of Artiflex Phakic intraocular lens (IOL) implantation in the treatment of high myopia. In this non-random interventional study, myopic patients with spherical equivalent worse than -5.0 diopters (D) who were not eli...

Arnett, D.R.; Jennings, J.L.; Tabb, D.L.; Link, A.J.; Weil, P.Anthony., 2008: A proteomics analysis of yeast Mot1p protein-protein associations: insights into mechanism. Yeast Mot1p, a member of the Snf2 ATPase family of proteins, is a transcriptional regulator that has the unusual ability to both repress and activate mRNA gene transcription. To identify interactions with other proteins that may assist Mot1p in it...

Zittle, R.X., 1960: The behavior of cardiovascular function in heart biopsy and in heart surgery and in surgery close to the heart. Thoraxchirurgie 8: 79-87

Takahashi, M.; Hood, D.A., 1993: Chronic stimulation-induced changes in mitochondria and performance in rat skeletal muscle. Chronic low-frequency (10-Hz) electrical stimulation was used to investigate mitochondrial biogenesis in rat tibialis anterior muscle. Succinate dehydrogenase and citrate synthase were used as mitochondrial enzymes, and cardiolipin (CL) was used a...

Roccella, M.; Pace, R.; D.G.egorio, M.T., 2003: Psychopathological assessment in children affected by Duchenne de Boulogne muscular dystrophy. Several studies on the intelligence of children suffering from Duchenne muscular dystrophy (DMD) found impairments in linguistic functions, memory and affective development. Memory deficit mainly involves long-term memory; short-term memory impair...

Morganoroth M.L.; Pickett W.C.; Worthen S.; Mathias M.; Reeves J.T.; Voelkel N.F., 1987: Decreased pulmonary vascular responsiveness in rats raised on an essential fatty acid deficient diet. Leukotriene C4 is produced during hypoxic pulmonary vasoconstriction and leukotriene inhibitors preferentially inhibit the hypoxic pressor response in rats. If lipoxygenase products are important in hypoxic vasoconstriction, then an animal deficie...

Adzhiev, B.L., 1975: hypertensive diseac blockaders/*admin. Klinicheskaia Meditsina 53(9): 31-34