Dynamics of floodplain vegetation under oil pollution in the Arctic zone

The significance of this research arises from the limited understanding of how floodplain plant communities in the Arctic region change in response to oil pollution. The objective of the study was to determine the trends in vegetation changes in areas affected by an accidental diesel fuel spill. The research focused on the floodplain plant communities of the Nadyezhdinsky Creek, as well as the Daldykan, Ambarnaya, and Pyasina rivers, examining both unpolluted (7 locations) and polluted areas (8 locations). The selection of study sites and the subsequent analyses were conducted using widely accepted geobotanical methods. A comparative analytical assessment of phytocenoses was performed through vegetation monitoring conducted from 2020 to 2022. The primary dynamic processes observed were linked to the emergence and extinction of species, with 53 species recorded in 2020, and 55 species from 17 families noted in both 2021 and 2022. Additionally, alterations in projective cover and shifts in the taxonomic ratios were documented. These changes were reflected in the abundance and diversity of species across various ecological groups. The cool and humid conditions experienced during the 2021 growing season promoted the proliferation of species typically associated with well-watered environments, including Equisetum arvense L. subsp. arvense, Equisetum fluviatile L., Eriophorum scheuchzeri Hoppe, and Carex aquatilis Wahlenb. s. str. In contrast, the warm and dry conditions in 2022 adversely affected these species, leading to their disappearance or a reduction in their projective cover. The predominant changes in vegetation dynamics from 2021 to 2022 can be characterized as fluctuations, regardless of the ecological context of the study sites, with no significant alterations in species composition or shifts in dominant species. Overall, there were no indications of catastrophic effects resulting from oil pollution. The observed changes in the plant communities were localized and primarily attributed to variations in climatic conditions and the specific hydrological characteristics of the individual water bodies.