Changes in the rates of floodplain and in-channel bench accretion in response to catchment disturbance, central Queensland, Australia

Hughes, Andrew O., Croke, Jacky C., Pietsch, Timothy J. and Olley, Jon M. (2010) Changes in the rates of floodplain and in-channel bench accretion in response to catchment disturbance, central Queensland, Australia. Geomorphology, 114 3: 338-347. doi:10.1016/j.geomorph.2009.07.016


Author Hughes, Andrew O.
Croke, Jacky C.
Pietsch, Timothy J.
Olley, Jon M.
Title Changes in the rates of floodplain and in-channel bench accretion in response to catchment disturbance, central Queensland, Australia
Journal name Geomorphology   Check publisher's open access policy
ISSN 0169-555X
1872-695X
Publication date 2010-01-15
Year available 2009
Sub-type Article (original research)
DOI 10.1016/j.geomorph.2009.07.016
Volume 114
Issue 3
Start page 338
End page 347
Total pages 10
Place of publication Amsterdam, Netherlands
Publisher Elsevier
Language eng
Formatted abstract
Analysis of the changes in rates of catchment sediment storage can provide material evidence of the impact of landscape disturbance on catchment sediment flux. A number of studies have suggested increased sediment yields from the rivers draining to the Great Barrier Reef since European settlement in the mid-nineteenth century. Many of these predictions, which indicate increases between four to ten times the pre-disturbance estimates, are based on large-scale catchment modelling that make some critical assumptions about pre-disturbance erosion rates and/or sediment delivery ratios. In addition, the majority have not been validated by empirical data. This study uses single-grain OSL dating and 137Cs depth profiles to determine pre- and post-floodplain accretion rates in Theresa Creek, a subcatchment of the dry-tropical Fitzroy River basin. We demonstrate that floodplain accretion rates have increased by three to four times since European settlement (ca. A.D. 1850). Decreased rates of floodplain accretion since the mid-twentieth century at sites contributed to by gullied terrain suggest a decrease in the supply of sediment derived from gully networks. In contrast, floodplain accretion rates from areas dominated by cultivation remain high. Widespread in-channel benches deposited since European settlement are stable and appear to be important stores of large volumes of sediment. Low magnitude increases in post-disturbance floodplain sedimentation rates (3 to 4 times), in comparison to those reported from mainly temperate climates (10 to 100 times), are attributed to the naturally high sediment loads typical of dry-tropical catchments. Consequently, previous predictions of large post-disturbance increases in sediment yields from large dry-tropical catchments draining to the Great Barrier Reef are likely to be overestimates.
Keyword Human impact
Sediment yield
Optical dating
137Cs depth profiles
Q-Index Code C1
Q-Index Status Provisional Code
Institutional Status Non-UQ
Additional Notes Published online 7 August 2009

Document type: Journal Article
Sub-type: Article (original research)
Collection: School of Geography, Planning and Environmental Management Publications
 
Versions
Version Filter Type
Citation counts: TR Web of Science Citation Count  Cited 18 times in Thomson Reuters Web of Science Article | Citations
Scopus Citation Count Cited 20 times in Scopus Article | Citations
Google Scholar Search Google Scholar
Created: Thu, 27 Nov 2014, 00:10:27 EST by Helen Smith on behalf of School of Geography, Planning & Env Management