Nature-based solutions enhance sediment and nutrient storage in an agricultural lowland catchment

In this paper, nature-based solutions (NBS) include: (1) natural flood management (NFM) interventions with a primary function of flood risk reduction but with additional multiple benefits for water quality improvements through the mitigation of diffuse pollution; and (2) ponds with a primary function of water quality improvement. This study assesses the ability of these NBS to trap pollutants in run-off within two small (3.4 km2) agricultural catchments (Upper Thames, UK). The masses of sediment, phosphorus, and organic carbon trapped by 14 features (since construction 2–3 years previously) were quantified through sediment surveying and sampling. Streamflow and suspended sediment monitoring downstream of features enabled catchment yields to be calculated. The features trapped a total of 83 t sediment, 122 kg phosphorus, and 4.3 t organic carbon. Although the footprint of the features was