Resch et al. (2025) Land use evolution as an indicator of hydrological change: historical trajectory of the Bassée floodplain, France (1850–1987)

Identification

• Journal: Regional Environmental Change
• Year: 2025
• Date: 2025-11-24
• Authors: Mathilde Resch, Laurence Lestel
• DOI: 10.1007/s10113-025-02490-x

Research Groups

• Sorbonne Université, CNRS, EPHE, UMR 7619 Metis, Paris, France

Short Summary

This paper investigates the historical land use evolution (1850–1987) of the Bassée floodplain, France, as an indicator of hydrological changes caused by hydraulic and navigation works, revealing three distinct stages of transformation from soil moisture control to floodplain disconnection.

Objective

• To evaluate the impacts of hydraulic and navigation works on the Bassée floodplain, in the Seine River valley (France), using land use evolution as a proxy for hydrological changes between 1850 and 1987.

Study Configuration

• Spatial Scale: Bassée floodplain, Seine River valley, France, specifically the lower part downstream of Bray-sur-Seine, with an approximate length of 60 km and an average width of 4 km.
• Temporal Scale: 1850–1987.

Methodology and Data

• Models used: GIS processing (rasterization, vectorization, cell value subtraction), Pixel Change Index (PCI), normalized Pixel Change Index (nPCI), transition matrices, Sankey diagrams.
• Data sources:
  • Quantitative: Cadastral plans (1824–1854), georeferenced vector layers from Institut Paris Région (MOS 1949), vegetation map by Bobe and Kovacs (1987).
  • Qualitative: Historical records from Archives of the Seine-et-Marne département and National Archives (engineering reports, correspondence, complaints, communal monographs), scientific literature, PIREN-Seine studies, reports from the French Ministry of the Environment.

Main Results

• The Bassée floodplain underwent three distinct stages of transformation: (i) controlling soil moisture (mid-19th century), (ii) disputes over lateral connectivity (late 19th to mid-20th century), and (iii) disconnection from the river (mid-20th century onwards).
• From the mid-19th century to 1949, wet meadows dramatically regressed from 65% to 3% of the study area, while cropland increased from 28.9% to 53.4%, forests to 26.7%, and plantations to 14%. A major change was the conversion of 30.6% of the study area from meadows to cropland.
• By 1987, wet meadows and wetlands were anecdotal (0.6%). Cropland slightly receded to 48.6% due to conversion into gravel pits (1.5%) and water bodies (8.3%). Forests continued to increase, partly from abandoned plantations.
• Hydraulic works (drainage, bypass canals, dykes, large reservoirs, river channelization) directly and indirectly impacted floodplain hydrology, leading to drying, reduced flooding frequency and magnitude, and lateral disconnection.
• The channelization of the Seine (1971–1979) increased flood peaks in Paris by 10–15 cm, effectively negating the flood retention effect of the Aube reservoir built in 1990.
• The threshold for Seine River overflow in the Bassée increased from 150 m³/s to 400 m³/s, making natural flooding increasingly rare.

Contributions

• Supplements existing geohistorical studies focused on river channels by providing a detailed analysis of the long-term impacts of hydraulic works on the floodplain.
• Addresses the general lack of attention paid to floodplains relative to main channels in geohistorical studies of watercourses.
• Confirms that navigation development on the Seine led to lasting changes in the floodplain, driven by a complex interplay of direct and indirect factors.
• Highlights the role of multiscale socio-environmental factors, power struggles, and conflicting visions of river management in shaping the floodplain's trajectory.
• Emphasizes the importance of a global, long-term vision and better coordination among stakeholders for effective river management and restoration, especially when using historical data to define reference states.
• Demonstrates the critical value of combining quantitative (GIS) and qualitative (archival) methods for a comprehensive understanding of past environmental changes and associated societal conflicts.

Funding

• PIREN-Seine (8th phase)

Citation

@article{Resch2025Land,
  author = {Resch, Mathilde and Lestel, Laurence},
  title = {Land use evolution as an indicator of hydrological change: historical trajectory of the Bassée floodplain, France (1850–1987)},
  journal = {Regional Environmental Change},
  year = {2025},
  doi = {10.1007/s10113-025-02490-x},
  url = {https://doi.org/10.1007/s10113-025-02490-x}
}