Please use this identifier to cite or link to this item:
|Title:||Sources, transport and deposition of terrestrial organic material in southwestern Africa|
Carr, Andrew S.
Chase, Brian M.
|Citation:||Quaternary Science Reviews, 2016, 149, pp. 215-229|
|Abstract:||Southwestern Africa's coastal marine mudbelt, a prominent Holocene sediment package, provides a valuable archive for reconstructing terrestrial palaeoclimates on the adjacent continent. While the origin of terrestrial inorganic material has been intensively studied, the sources of terrigenous organic material deposited in the mudbelt are yet unclear. In this study, plant wax derived n-alkanes and their compound-specific δ13C in soils, flood deposits and suspension loads from regional fluvial systems and marine sediments are analysed to characterize the origin of terrestrial organic material in the southwest African mudbelt. Soils from different biomes in the catchments of the Orange River and small west coast rivers show on average distinct n-alkane distributions and compound-specific δ13C values reflecting biome-specific vegetation types, most notably the winter rainfall associated Fynbos Biome of the southwestern Cape. In the fluvial sediment samples from the Orange River, changes in the n-alkane distributions and compound-specific δ13C compositions reveal an overprint by local vegetation along the river's course. The smaller west coast rivers show distinct signals, reflecting their small catchment areas and particular vegetation communities. Marine surface sediments spanning a transect from the northern mudbelt (29°S) to St. Helena Bay (33°S) reveal subtle, but spatially coherent, changes in n-alkane distributions and compound-specific δ13C, indicating the influence of Orange River sediments in the northern mudbelt, the increasing importance of terrigenous input from the adjacent western coastal biomes in the central mudbelt, and contributions from the Fynbos Biome to the southern mudbelt. These findings indicate the different sources of terrestrial organic material deposited in the mudbelt, and highlight the potential the mudbelt has to preserve evidence of environmental change from the adjacent continent|
|Rights:||Copyright © the authors, 2016. After an embargo period this will be an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial-No Derivatives License (http://creativecommons.org/licenses/by-nc-nd/4.0/), which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made.|
|Description:||The file associated with this record is under a 24 month embargo from publication in accordance with the publisher's self-archiving policy. The full text may be available through the publisher links provided above.|
|Appears in Collections:||Published Articles, Dept. of Geography|
Files in This Item:
|Manuscript_NH_revised_final_QSR.pdf||Post-review (final submitted author manuscript)||1.47 MB||Adobe PDF||View/Open|
Items in LRA are protected by copyright, with all rights reserved, unless otherwise indicated.