Tims, StephenEverett, SarahFifield, L KeithHancock, GaryBartley, Rebecca2015-12-100168-583Xhttp://hdl.handle.net/1885/57017Plutonium fallout from atmospheric nuclear-weapons testing in the 1950s and 1960s constitutes an artificial tracer suitable for the study of recent soil erosion and sediment accumulation rates. Traditionally 137Cs has been the fallout isotope of choice for such studies, but the plutonium isotopes confer a number of advantages, which can be realised using the ultra-sensitive detection technique of Accelerator Mass Spectrometry (AMS). As a first application of plutonium to a whole-of-basin study, Pu has been measured in both soil and sediment across the catchment of the Herbert River, which is one of the major rivers draining into Australia's Great Barrier Reef Lagoon. Its catchment includes undisturbed areas as well as regions of pasture and sugar cultivation. The Pu measurements allow the relative contributions of surface and gully erosion from the different land use areas to be determined, and permit the discharged material to be apportioned between the relevant sources. CrownKeywords: Accelerator mass spectrometry; Artificial tracers; Australia; Great Barrier Reef; Gully erosion; Isotope ratio; Isotope ratios; Plutonium isotopes; Relative contribution; Sediment accumulation; Sensitive detection; Soil and sediment; Soil erosion; Agricul AMS; Erosion; Isotope ratios; Plutonium; Sediment transport201010.1016/j.nimb.2009.10.1212016-02-24