Record Details
Field | Value |
---|---|
Title | Diploptene : an indicator of terrigenous organic carbon in Washington coastal sediments |
Names |
Prahl, Fredrick
(creator) Hayes, J. M. (creator) Xie, T.-M. (creator) |
Date Issued | 1992 (iso8601) |
Abstract | The pentacyclic tritcrpene 17β(H), 21β(H)-hop-22(29)-ene (diploptence) occurs in sediments throughout the Columbia River drainage basin and off the southern coast of Washington state in concentrations comparable to long-chain plantwax n-alkanes. The same relationship is evident for diploptene and long-chain n-alkanes in soils from the Willamette Valley. Microorganisms indigenous to soils and soil erosion are indicated as the biological source and physical process, respectively, for diploptene in coastal sediments. Similarity between the stable carbon isotopic composition (δ¹³CPDB) of diploptene isolated from soil in the Willamette Valley (- 31.2 ±0.3%₀) and from sediments deposited throughout the Washington coastal environment (- 31.2 ± 0.5%₀) supports this argument. Values of 6 for diploptene in river sediments are variable and 8-l7% lighter, indicating that an additional biological source such as methane-oxidizing bacteria makes a significant contribution to the diploptene record in river sediments. Selective biodegradation resulting from a difference in the physicochemical association within eroded particles can explain the absence of the more ¹³C-depleted form of diploptene in Washington coastal sediments, but this mechanism remains unproven. |
Genre | Article |
Identifier | Prahl, F., Hayes J. M., Xie, T. M. (1992). Diploptene: an indicator of terrigenous organic carbon in Washington coastal sediments. Limnology and oceanography, 67(6), 1290-1300. |