Dataset on total mercury (Hg) concentrations in soil, sediment, and fish from a recreationally impacted lake ecosystem (Gölcük Nature Park, Türkiye

This dataset contains total mercury (Hg) concentrations measured in surface soils, lake sediments, and fish tissues collected from Gölcük Nature Park (Bolu, Türkiye). Sampling was conducted during summer (July 2019) and winter (March 2020) to investigate seasonal variability and environmental distribution patterns. The dataset includes spatial coordinates, sample characteristics, and Hg concentrations (ng/g), supporting the analysis of Hg transport, accumulation, and environmental fate in a recreationally influenced ecosystem