Quantifying sources of suspended sediment in three size fractions

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tions of both source and suspended samples including fine silt and clay (
J Soils Sediments DOI 10.1007/s11368-015-1196-1

ADVANCES IN SEDIMENT FINGERPRINTING

Quantifying sources of suspended sediment in three size fractions Arman Haddadchi 1 & Jon Olley 1 & Timothy Pietsch 1

Received: 30 June 2014 / Accepted: 3 July 2015 # Springer-Verlag Berlin Heidelberg 2015

Abstract Purpose Identifying of the sources, stores and pathways of sediments in a catchment is essential to accurately target management actions designed to reduce sediment delivery to receiving waters. Fingerprinting the source of sediment using geochemical properties has increasingly been accepted as an accurate approach for quantifying the contribution of different sources to river sediment discharge. In this study, we seek to examine the effect of particle size and location of the sources on their contribution to suspended sediments. Materials and methods Geochemical tracers (n=41) were employed to calculate proportional contributions of sediment to Emu Creek, a predominantly pastoral catchment (911 km2) in south-eastern Queensland, Australia. The study focused on two high flow events (10- and 6-year return periods) and some lower flow events which occurred during the 18 months from October 2011 to March 2013. Source contributions were determined at eight spatially distributed sites in major tributaries and along the main channel of Emu Creek. Source determination at the in-stream sites was done using end member samples (based on the underlying rock type) collected upstream of the site of interest, thus indicating how different sources dominate at different locations downstream. To examine whether different size fractions shared similar provenances, three size fractions of both source and suspended samples including fine silt and clay (