Entropy-based assessment data for the ecological state of the Dnipro Reservoir, Ukraine, 2003–2022

This dataset contains 1607 surface-water quality observations from eight monitoring stations in the Dnipro Reservoir and adjacent Dnipro–Donbas Canal, Ukraine. The data cover the period 2003–2022, although the temporal coverage differs among stations. The dataset includes eleven indicators used in the related publication: biochemical oxygen demand over five days (BOD5), suspended solids, dissolved oxygen, sulfate, chloride, ammonium, nitrate, nitrite, phosphate, synthetic surfactants, and chemical oxygen demand (COD). The package provides station-level observation data, station coordinates, average indicator values, counts of exceedances of reference values, and the calculated entropy water-quality index G for eight monitoring points. Numeric zeros in measurement fields were treated as absent values according to the dataset owner's established missing-value convention. No values were imputed. Original non-zero numerical values were retained without recalculation. Primary monitoring source: State Agency of Water Resources of Ukraine, https://data.gov.ua/dataset/surface-water-monitoring. Related publication: Bezsonnyi, V. L., Tretyakov, O. V., Plyatsuk, L. D., and Nekos, A. N. (2022). “Entropy approach to assessment of the ecological state of a water course.” Visnyk of V. N. Karazin Kharkiv National University, Series Ecology, 27, 6–19. https://doi.org/10.26565/1992-4259-2022-27-01.