Purpose. The purpose of the work is to estimate the long-term variations in concentration and flux of nutrients (inorganic nitrogen and inorganic phosphorus) in atmospheric deposition in Sevastopol.

Methods and Results. During 2015–2023, the samples of atmospheric deposition in Sevastopol were collected to analyze the concentration of dissolved forms of inorganic nitrogen (nitrate, nitrite and ammonium) and phosphorus. For each precipitation event, two types of samplers were used – the open and wet-only ones. Laboratory analysis of the collected samples was carried out in FSBSI FRC "Marine Hydrophysical Institute". A total of 1264 samples of atmospheric deposition were analyzed. The maximum content of nutrients was determined in the samples with minimum precipitation amount, or after a long dry period. The concentrations of inorganic forms of nitrogen in the samples from the open sampler were 1.3 times higher than those from the wet-only one. The phosphorus content in the open sampler exceeded that in the wet-only one by 3 times. The increased concentrations of ammonium in atmospheric deposition were revealed in spring, while those of nitrates – in fall-winter. The phosphorus flux in the samples from the open sampler reached its maximum value in fall and exceeded the winter flux by 2.3 times.

Conclusions. The long-term variation in inorganic nitrogen flux is of a quasi-periodic pattern: its maximum flux was observed in 2017, and the minimum one – in 2019–2020. The maximum phosphorus flux in the samples from the wet-only sampler was noted in 2017–2018, whereas the phosphorus flux in the samples from the open sampler in 2021–2022 exceeded the flux in 2017–2018 by 1.5 times. As for inorganic nitrogen, its annual contribution to atmospheric deposition amounted 9.4–11.5% of a river runoff, and as for phosphorus – 16.7–55.6%. During the low-water period, these values were 12–14% and 20–65%, respectively.