Description
Understanding soil erosion, and the transport of soil / sediment through fluvial catchments is fundamental when thinking about holistic catchment management including interventions to manage water such as Natural Flood Management e.g., buffer strips. The River Derwent, Yorkshire has a recognised fine grained sediment problem, impacting water treatment costs, however there is little information within the catchment related to source areas of sediment including soil erosion. Much of the catchment is dominated by agriculture (40%) and lowland areas (51% <57m). The catchment is complex and contains 14 soil types delineated by European Soil Database. The Soil Water Assessment Tool (SWAT) was used to model soil erosion within the catchment to understand the wider sediment budget of the River Derwent and calibrated using gauge records using SUFI 2. The model, which integrates soil information such as texture, organic matter, saturated hydraulic conductivity and soil erodibility (K).SWAT showed distinct variation across the catchment, with lower than expected volumes contributed from the middle and lower catchment; especially in areas surrounding the main trunk river of the Derwent; 80% of sediment yield relates to the Upper Rye and Upper Derwent. Overall, the modelling shows the River Derwent contributes 12% of the wider Ouse Catchment sediment budget. In-channel samples were collected and tested for water quality parameters such as total suspended solids, turbidity, nitrate. The in-channel samples show locally soil erosion is important, however at a catchment scale flow rate is the limiting factor for fine-grained sediment entrainment. Thirty years of weather data was integrated into the SWAT, however, questions relate to extreme events and thresholds within the model to initiate soil erosion, especially as more extreme localised events are predicted due to climate change.
| Period | 2024 |
|---|---|
| Held at | British Society of Soil Science , United Kingdom |
| Degree of Recognition | National |