| During the field observation period, 75 and 198 rainwater samples, 155 and 174 aerosol samples were collected at Qianliyan and Shengsi Archipelago, respectively. Major anions and cations and some inorganic nutrients were analyzed. The anions (F~, Cl- and SO42-) were analyzed by IC(Ion Chromatography) and cations (K+, Na+, Ca2+ and Mg2+) by FAAS (Flame Atomic Absorption Spectrometry) and nutrients(NFLf+, NO3-, NO2-, PO43- and SiCb2") by autoanalyser. The quality control was undertaken for all the species studied.The results show that good correlation exits between the total anions and cations, but most of the ratios for S-/2+ are less than 1.00, which indicates that some of the amions may be neglected during the analyses. In general, the samples at Qianliyan have high values than that at Shengsi, however the two sites have the similar ion composition. Cl" and Na+, which mainly come from the marine aerosols, are major ions of the precipitation. A general trend of rapid decrease of element concentrations with higher rainfall occurred, except for fT. The trend for H+ is complicated and no obviously characteristic can be observed. The monthly average concentrations have notable seasonal features and high values always occur at winter and/or spring and low values at summer.65% of the precipitations at Shengsi and 40% at Qianliyan are acid rain. At Shengsi positive relativity exits between FT and nss-SO42" and NOa", but it is to less extent at Qianliyan. With the increasing of concentration for NH? and/or nss-Ca2+, concentration for VT decreases. The statistic results show that good correlations exit between the species, which have the same or similar resources. Similar results can be obtained by the three methods.The concentrations for nutrients also have obvious seasonal characteristics but have much difference in composition with that in seawater. During the observation period, the annual average concentration for most of nutrients increased except for SiO?:" atShengsi. The fluxes for dissolved inorganic nitrogen have the similar values at the two sites but PO43~ has higher values at Qianliyan and SiOa2" at Shengsi. Wet deposition is the major source of freshwater for Yellow Sea; accounting for 58.3%, but it is not true for East China Sea where wet deposition can only supply 46.0% of the freshwater.The aerosols at Qianliyan have high values at spring; two times more than other seasons, however high values may occur in winter and/or spring at Shensi. 34.2% of the minerals inputted into the Yellow Sea were by the atmospheric deposition and only 1.34% for East China Sea. Ultrasound leaching was chosen to analyze the dry deposition samples after comparison with the re-circulation. The aerosols at Qianliyan have high concentrations for PCU3' and SiOs2" and at Shensi high values for NHt+ and NCV can be observed.All of the nutrients in aerosols have higher values in the sandstorm period and samples at Qianliyan have higher values for the species studied than that at Shengsi. The wet deposition fluxes for the nutrients were larger than the dry one at the two sites. Compared with the river input, the atmospheric deposition is the major source for NHt+ at the studied area and the other nutrients are mainly inputted into the sea by river. DIN inputted by air plays an important role in the new production of Yellow Sea and East China Sea, but to less extent for PCu3" and SiOa2".The results of the incubation show that with addition of rainwater which contains high N and low P, concentrations of chlorophyl in the seawater increase significantly although limited by P. Similar results can be observed either added only once or consecutively.
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