# Contribution of Atmospheric Depositions to Inventory of Nutrients in the Coastal Waters of Crimea
## 3 Results and Discussion  
Statistics for concentrations of nutrients in atmospheric precipitations and in seawater after precipitations have taken place are presented in Tables 1 and 2. The average inorganic nitrogen flux with atmospheric precipitations in Sevastopol is 24.49 mmol m\({}^{-2}\) year\({}^{-1}\) for wet-only depositions and 30.17 mmol m\({}^{-2}\) year\({}^{-1}\) for the sum of wet and dry depositions. The phosphate average flux in Sevastopol is 0.14 and 0.38 mmol m\({}^{-2}\) year\({}^{-1}\) for wet-only and the sum of wet and dry depositions, respectively. The difference is about two-fold between silica fluxes with wet-only and the sum of wet and dry depositions: 0.31 mmol m\({}^{-2}\) year\({}^{-1}\) for the wet-only depositions, and 0.69 mmol m\({}^{-2}\) year\({}^{-1}\) for the sum of wet and dry depositions. This large difference in wet and dry fluxes of phosphorus and silica may be due to deposition of terrigenous particles resulting from dust transportation from, for example, the deserts of Syria and the Sahara [33] and the spring and autumn following of agricultural fields in Crimea. We carry out quarterly monitoring of the water quality of Sevastopol Bay. Concentrations of nutrients are routinely determined. We consider the average nutrients concentration obtained during monitoring in different seasons as ambient concentration in this work. The ambient concentrations of inorganic nitrogen, phosphates and silica in surface layer of the bay are presented in Table 3.  
The concentration of nutrients in the surface layer of Sevastopol Bay may significantly exceed the average ambient value after atmospheric precipitations. The maximum concentration of inorganic nitrogen in the surface water layer after atmospheric precipitation has exceeded the ambient value 17-fold in summer (62.21 mmol L\({}^{-1}\)) and 3.5-fold in winter (26.51 mmol L\({}^{-1}\)). This difference is 4- and 48-fold for inorganic phosphorus (0.24 mmol L\({}^{-1}\) and 1.92 mmol L\({}^{-1}\)) and is 11- and 9-fold for silica (25.48 mmol L\({}^{-1}\) and 19.18 mmol L\({}^{-1}\)) in summer and winter, respectively. The concentration of nutrients in surface waters of the bay usually decreases \begin{table}
\begin{tabular}{c c c c c c c} \hline  & \multicolumn{2}{c}{**Nitrogen**} & \multicolumn{2}{c}{**Phosphorus**} & \multicolumn{2}{c}{**Silica**} \\ \cline{2-7}  & **Wet-Only Sampler** & **Open Sampler** & **Wet-Only Sampler** & **Open Sampler** & **Wet-Only Sampler** & **Open Sampler** \\ \hline Max, \(\mu\)mol L\({}^{-1}\) & 465.76 & 799.58 & 18.17 & 45.65 & 34.46 & 36.79 \\ \hline Min, \(\mu\)mol L\({}^{-1}\) & 17.42 & 17.00 & 0 & 0 & 0 & 0 \\ \hline VWM, \(\mu\)mol L\({}^{-1}\) & 71.21 & 86.44 & 0.37 & 1.01 & 0.77 & 1.77 \\ \hline St. deviation, \(\mu\)mol L\({}^{-1}\) & 64.81 & 95.53 & 1.45 & 3.98 & 2.69 & 4.56 \\ \hline \end{tabular}
\end{table} 
Table 1: Statistics for nutrients concentration in atmospheric depositions in Sevastopol. \begin{table}
\begin{tabular}{c c c c} \hline  & **Nitrogen** & **Phosphorus** & **Silica** \\ \hline Max, \(\mu\)mol L\({}^{-1}\) & 62.21 & 1.92 & 25.48 \\ \hline Min, \(\mu\)mol L\({}^{-1}\) & 0.47 & 0 & 0.51 \\ \hline Average, \(\mu\)mol L\({}^{-1}\) & 10.16 & 0.16 & 3.73 \\ \hline St. deviation, \(\mu\)mol L\({}^{-1}\) & 8.15 & 0.17 & 2.95 \\ \hline \end{tabular}
\end{table} 
Table 2: Statistics for nutrients concentration in seawater after atmospheric precipitations in Sevastopol. \begin{table}
\begin{tabular}{c c c c} \hline  & **Nitrogen**, \(\mu\)mol L\({}^{-1}\) & **Phosphorus**, \(\mu\)mol L\({}^{-1}\) & **Silica**, \(\mu\)mol L\({}^{-1}\) \\ \hline Spring & 3.88 & 0.03 & 1.85 \\ \hline Summer & 3.54 & 0.06 & 2.25 \\ \hline Fall & 6.27 & 0.08 & 3.80 \\ \hline Winter & 7.53 & 0.04 & 2.03 \\ \hline \end{tabular}
\end{table} 
Table 3: The ambient concentrations of nutrients concentrations in surface layer of Sevastopol bay. to ambient values in the next 4-5 days after precipitation.