Combining contemporary and long-term erosion rates to target erosion hot-spots in the Great Barrier Reef, Australia

摘要: Abstract Methods for prioritising catchment remediation are based on understanding the source of sediment over short-medium timescales (10–10 2 years) using techniques such as finger-printing, flux monitoring, and modelling. Because approaches do not necessarily quantify natural variation in longer timescale, they often represent background or pre-agricultural erosion rates poorly. This study compares long-term (∼100 to >10,000 derived from terrestrial cosmogenic nuclides ( 10 Be) with contemporary obtained by monitoring fluxes #11×10#10 years. The ratio these two data sets provides a measure accelerated factor (AEF), which can be used identify hot-spots at sub-catchment scale. area is Burdekin catchment, largest Great Barrier Reef lagoon. Long-term vary −1 Suttor Belyando sub-catchments 0.0296 mm yr Bowen. highest small hillslopes patchy ground cover (0.2726 mm yr ) Bowen (0.2207 mm yr ), lowest (0.0019 mm yr ). All but sites have an AEF > 1.0, indicating higher than estimated averages. Results confirm that agriculturally-induced increased considerably. Within context Water Quality Protection Plan, results provide justification water quality targets set scale, particularly large geomorphically diverse catchments.