Topic III - Environmental issues > III-2-Using lake sediments to trace soil health and agricultural practices across watersheds

Conveners

1. Floriane Guillevic (Department of Environmental Sciences, Univ. Basel, Switzerland),
2. Pierre-Alexis Chaboche (Laboratoire des Sciences du Climat et de l'environnement, Paris, France)
3. William Rapuc (EDYTEM, CNRS, Univ. Savoie Mont Blanc, France)
4. Jérôme Poulenard (EDYTEM, Univ. Savoie Mont Blanc, France)

Human activities over the past centuries, particularly since the "Great Acceleration" period, have driven rapid environmental changes, transforming ecosystems and accelerating soil degradation. Soils play a fundamental role in food security, water quality, and climate regulation by sequestering carbon, while lakes can preserve continuous sediment records that serve as environmental archives for reconstructing soil changes over time.

We encourage studies that combine sediment and soil analyses to investigate factors such as nutrient imbalances, contaminants dynamics (e.g., PTEs, PAHs, pesticides, and microplastics), and land-use changes (e.g. deforestation, agriculture expansion) that impact soil quality. At the watershed scale, researchers will present insights on the speed and scale of soil quality changes, patterns of soil erosion recorded in lake sediments, and the potential delayed response of water bodies within watersheds – findings that are essential for the critical zone community.

This session will allow to connect sediment records with soil, document landscapes changes through the Holocene to the present day and emphasize the need for sustainable land management practices to preserve soil health.