Dry deposition characteristics of atmospheric reactive silicate at Jiaozhou Bay and its potential ecological effects on marine ecosystem

As one of the important ways for land-derived materials to be transported into the sea, atmospheric deposition has become one of the hotspots in the international cross-study of atmospheric science, marine science and environmental science. The settlement of biogenic elements in the atmosphere may have an important impact on marine ecosystems. Based on this, the Jiaozhou Bay, a typical bay in northern China, was selected to collect aerosol total suspended particulate matter (TSP, Total Suspended Particulate) and dry sedimentation samples for a period of one year (June 2015 to May 2016). The content of reactive silicate (SiO3-Si, Reactive Silicate) is analyzed, and on this basis, the concentration of SiO3-Si in the atmosphere, dry deposition flux and dry deposition velocity (Vd, Dry Deposition Velocity) are analyzed, and a preliminary assessment is made. The results show that the average annual concentration of SiO3-Si in the atmospheric TSP of Jiaozhou Bay is (1.98±1.22) nmol/m3, which is low in summer and autumn and high in winter and spring. Atmospheric SiO3- The Si concentration showed a significant declining gradient from the coast of Qingdao to the Yellow Sea and the East China Sea. Combined with correlation analysis, it is shown that the long-distance transmission of sand dust in Asia and the resuspension of mineral dust are the main sources of SiO3-Si in the atmosphere at the margin of the eastern shelf of China. The dry deposition flux of SiO3-Si was 8.48 mmol m-2 a-1, and the deposition load reached 87.8 t/a, which was significantly higher than the wet deposition in the same period. It can account for the external input of SiO3-Si in Jiaozhou Bay (including dry and wet deposition and river input). ), indicating that dry deposition is one of the important input sources of SiO3-Si in Jiaozhou Bay. The lower Si:N molar ratio (0.16±0.22) in dry deposition implies that atmospheric dry deposition may have caused the Jiaozhou Bay for a long time An important potential factor for Si limitation in water bodies. The SiO3-Si input caused by dry settlement can be estimated based on the Redfield ratio to support a new productivity of 674 mg C m-2 a-1, which can account for 5.3% of the new productivity in Jiaozhou Bay, indicating that atmospheric SiO3 The dry deposition of -Si will have a certain impact on the Jiaozhou Bay ecosystem. This research system analyzed the dry deposition characteristics of atmospheric SiO3-Si in Jiaozhou Bay, and evaluated the dry de