puits (1) érosion du sol (1) sol (1) racine (1) pollen (1) parasite (1) cheptel sur pied (1) lac (1) indicateur (1) fougère (1) érosion (1) Trampling (1) Hazel (1) Anabaena (1) Wetlands (1) Values (1) Value (1) Solanum (1) Soils (1) Soil erosion (1) Rotifera (1) Bracken fern (1) Pollen (1) Persons (1) Oak (1) Neolithic period (1) Maple (1) Human beings (1) Livestock (1) Impact (1)