1 Material which has separated and settled out from the medium—wind, water, or ice—which originally carried it. For fluvial sediments the ability of a river to carry sediment depends on particle size as well as the river discharge. See also load. A sediment slug is a body of clastic material associated with disequilibrium conditions in fluvial systems over time periods above the event scale. Slugs range in magnitude from unit bars to sedimentary features generated by basin-scale sediment supply disturbances; see Nicholas et al. (1995) PPG 19, 4, 500.

2 A sediment budget is the tally of inputs and outputs for a specific open system, over a given time period; the classic paper is Trimble (1983) Am. J. Sci. 283. A balanced sediment budget is an equation of mass conservation in which the sediment fluxes related to the sources, sinks, and storages are balanced. The concept is important in environmental management: see Nordstrom et al. (2002) Geomorph. 47, 2–4.