Soil physical and chemical properties along a 300 m transect, Stara Huta (fen), Tuchola Forest, Poland

Soil physical and chemical properties collected along a 300 m transect across Stara Huta fen (Tuchola Forest, northern Poland) in November 2025, as part of NCN Miniatura-9 project (DEC-2025/09/X/ST10/00359). The dataset covers seven sampling points from the mineral margin to the active peatland boundary, across three functional zones delineated using LiDAR-derived elevation contours. Parameters include bulk density, gravimetric and volumetric water content, total porosity, water saturation, water holding capacity, TOC, TN and C:N ratio in soil (0–10 cm and 10–20 cm layers; additional 50–60 cm layer at point S7). The site is a degraded minerotrophic fen (fen after drainage) with dominant moorsh (mursh) formation in the central zone. Active peatland centre was not sampled due to safety conditions. Supplementary files include LiDAR-derived elevation profile and field photographs. This dataset is a companion to the Komorze raised bog dataset (doi:10.5281/zenodo.21132004) collected within the same project.