Keeping Up with Phosphorus Dynamics: Perspective article published

Together with colleagues from the UK, we published an article in Frontiers in Environmental Science in which we make a case for a more holistic approach in vegetated filter strip (VFS) research, design, policy, and implementation.

The paper can be downloaded for free at: https://www.frontiersin.org/articles/10.3389/fenvs.2022.764333/full

Schematic overview of key pathways, processes, and cycling of phosphorus in VFS.

Focussing on phosphorus (P), we describe the downfalls of current approaches and ways for improvement. In a VFS, the amount of incoming P must not exceed the amount of P that the soil can retain and the amount of P that can be removed, e.g., by harvesting the vegetation. This requires comprehensive VFS designs in accordance to actual runoff and erosion patterns and a more flexible positioning in line with local conditions. Designs and evaluations of VFS that match the complexity of the processes involved are crucial for the effective and long-term protection of surface waters.

We hope that this article stimulates a much needed discussion on the potential and limits of state-of-the-art VFS.

Soil core sampling started

In November, we started with the soil sampling for work package 2. For the first two sites, we have chosen an intensive sampling scheme, using soil cores along transects from the field to the buffer strip, as well as inside and outside of the area of concentrated runoff. Together with samples from different depth classes from the soil cores, we get a 3D representation of the field and buffer strip. This labour-intensive approach is rarely seen in buffer strip research, although it provides high quality data and ample opportunities for in-depth analyses. The samples will then be analysed for various physical and chemical parameters, with a focus on phosphorus (e.g. different P pools, degree of P saturation, P sorption index). Further sites will get sampled next year.

Grassed strips between fields and surface waters act as buffers and retain sediment and nutrients. (C) BAW-IKT / Ramler
Agricultural areas can export substantial amounts of sediment – and nutrients – after heavy rainfall events. (C) BAW-IKT / Ramler