Abstract
Within agricultural watersheds suspended sediment-discharge hysteresis during storm events is commonly used to indicate dominant sediment sources and pathways. However, availability of high-resolution data, qualitative metrics, longevity of records, and simultaneous multiwatershed analyses has limited the efficacy of hysteresis as a sediment management tool. This two year study utilizes a quantitative hysteresis index from high-resolution suspended sediment and discharge data to assess fluctuations in sediment source location, delivery mechanisms and export efficiency in three intensively farmed watersheds during events over time. Flow-weighted event sediment export was further considered using multivariate techniques to delineate rainfall, stream hydrology, and antecedent moisture controls on sediment origins. Watersheds with low permeability (moderately- or poorly drained soils) with good surface hydrological connectivity, therefore, had contrasting hysteresis due to source location (hillslope versus channel bank). The well-drained watershed with reduced connectivity exported less sediment but, when watershed connectivity was established, the largest event sediment load of all watersheds occurred. Event sediment export was elevated in arable watersheds when low groundcover was coupled with high connectivity, whereas in the grassland watershed, export was attributed to wetter weather only. Hysteresis analysis successfully indicated contrasting seasonality, connectivity and source availability and is a useful tool to identify watershed specific sediment management practices.
Original language | English |
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Pages (from-to) | 1769-1778 |
Number of pages | 10 |
Journal | Environmental Science and Technology |
Volume | 50 |
Issue number | 4 |
Early online date | 19 Jan 2016 |
DOIs | |
Publication status | Published - 16 Feb 2016 |
ASJC Scopus subject areas
- General Chemistry
- Environmental Chemistry
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Dive into the research topics of 'Storm Event Suspended Sediment-Discharge Hysteresis and Controls in Agricultural Watersheds: Implications for Watershed Scale Sediment Management'. Together they form a unique fingerprint.Student theses
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Soil erosion and suspended sediment dynamics in intensive agricultural catchments
Sherriff, S. C. (Author), Rowan, J. (Supervisor), Ó hUallacháin, D. (Supervisor), Fenton, O. (Supervisor), Jordan, P. (Supervisor) & Melland, A. R. (Supervisor), 2015Student thesis: Doctoral Thesis › Doctor of Philosophy
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Profiles
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Rowan, John
- Energy Environment and Society - Director of UNESCO Centre for Water Law Policy and Science & Physical Geography
Person: Academic