Land-use history and sediment flux in a lowland lake catchment: Groby Pool, Leicestershire, UK

<jats:p> Whole-basin sediment records have been used to investigate the impact of land-use change and catchment processes on sediment flux to Groby Pool, Leicestershire, UK, over the past c. 200 years. Estimates of sediment yields for the period ad 1945–1989 were calculated using dry mineral mass data from multiple cores. Up-core changes in loss-on-ignition values were used to correlate cores and these were tied to a master chronology based on <jats:sup>210</jats:sup>Pb and 137Cs profiles. Sediment sources within the catchment were identified by comparing the magnetic properties of lake sediment, soil and stream samples. In addition, documentary records were used to establish the pattern of land-use change and other activities which might affect material flux to the lake. A lakewide change in sediment type is recorded after Parliamentary Enclosure in 1789, as the focus of arable activity shifted from outside to inside the lake's drainage catchment. Trends in lake sediment mineral magnetic properties also indicate a slight shift in the source of allochthonous inputs, from subsoil to topsoil derived material at that time. Recent changes in mineral magnetics are thought to reflect the changing supply of subsoil flux resulting from modifications to inlet streams coupled with increased inputs of atmospheric pollutants. Sediment yield estimates of 18 t km<jats:sup>-</jats:sup><jats:sup>2</jats:sup> yr<jats:sup>-</jats:sup><jats:sup>1</jats:sup>, obtained for the period 1945–1989, are similar to other lowland UK sites with similar lake/catchment ratios. Activities such as quarrying, road construction and agricultural intensification appear to have had little or no impact on sediment yields to the lake in recent times. This is thought to be due to the interplay between catchment and instream storage, a low drainage density and the buffering effect of riparian vegetation. </jats:p>