EGU25-17782, updated on 15 Mar 2025
https://doi.org/10.5194/egusphere-egu25-17782
EGU General Assembly 2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
Field patterns as game changers of the sediment connectivity
Matthieu Herpoel, Adrien Michez, and Aurore Degré
Matthieu Herpoel et al.
  • Agro-Bio Tech, Uliege, Gembloux, Belgium

In Northwestern Europe, sediment transport from agricultural fields to rivers has significant off-site impacts, influenced by connectivity between landscape elements. Sediment connectivity, assessed  using the index of connectivity (IC) developed by Borselli et al. (2008), is shaped by landscape configuration, including features like field boundaries that divide land parcels. Effective management requires understanding these interactions to mitigate soil erosion. IC depends on factors enhancing (upstream area and slope) or impeding (downstream distance and impedance) connectivity, with impedance estimation being particularly challenging to quantify due to vegetation effects. One such effect is the alternation of crops along slopes, a practice known as strip cropping, which is widely recognised in the literature as an effective strategy to reduce connectivity and improve soil conservation. This study proposes refining the IC weighting factor by incorporating parcel connectivity, thereby better reflecting the impact of agricultural landscape fragmentation. We focused on the Dyle sub-catchment in Belgium, where the organisation of agricultural parcels is suboptimal, with 40% of crop sequences along concentrated flow paths  consisting of crops from the same category (e.g., spring crops or winter cereals). We applied the revised IC using high-resolution data (1 m × 1 m) to compare different parcel fragmentation scenarios. Fragmented landscapes yield lower connectivity values, indicating greater sediment disconnection. This is especially pronounced along concentrated flow paths, where up to 49% of the least connected flow paths are disconnected compared to non-fragmented setups. Isoline-based parcel fragmentation emerged as highly effective, promoting larger parcel sizes and better disconnection on concentrated flow paths. These results emphasize the opportunities for improved management of agricultural landscapes in order to reduce sediment connectivity through appropriate land use practices and parcel configurations.

How to cite: Herpoel, M., Michez, A., and Degré, A.: Field patterns as game changers of the sediment connectivity, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-17782, https://doi.org/10.5194/egusphere-egu25-17782, 2025.