Controls on the phosphorus content of fine stream bed sediments in agricultural headwater catchments at the landscape-scale

There have been no landscape-scale assessments which quantify the relative importance of the organic and mineral properties of BS (bed sediment) and associated catchment characteristics (geology, land cover and mean topsoil phosphorus (P) content) for BSP concentration. Mid infra red diffuse reflectance spectrometry was applied to estimate the quantities of organic matter, dithionite extractable aluminium- (Ald) and iron (Fed), kaolinite, dioctahedral clay and mica (D&M) minerals in 1052 snapshot samples of fine (<150 μm) BS in small to medium-sized (5–55 km2) agricultural headwater catchments across a large area (15 400 km2) of central England. Analyses included estimates of BS specific surface area, cerium (Ce) concentrations (enriched in P-bearing apatite and P-fertilsers), and catchment average topsoil P content.