Multi-element dataset from a 3000-year soil chronosequence in the Yangtze River floodplain

This dataset was collected to test the hypothesis that long-term land reclamation and different land-use types significantly affect the accumulation, migration, and coupling behavior of multiple soil elements. Soil samples were collected from dryland, paddy fields, and coastal tidal flats, with a consistent sampling depth of 0–20 cm. The concentrations of more than 40 elements, including rare earth elements (REEs), heavy metals, and other trace elements, were determined using ICP-MS after acid digestion. This dataset can be used to evaluate how land-use changes influence soil elemental cycling, and it is suitable for studies in biogeochemistry, environmental assessment, and sustainable land management. Sufficient metadata and method descriptions are provided to allow others to interpret and reuse the data effectively.