| Summary: | 碩士 === 國立臺灣海洋大學 === 海洋環境資訊系 === 106 === In this study, wet deposition of atmosphere was collected from Keelung (costal city), which was located south of the East China Sea (ECS), from August 2015 until July 2016. 86 samples were collected and were analyzed to examine the total dissolved nitrogen (TDN), total dissolved phosphorus (TDP) and major ions in these samples. TDN can be divided into dissolved inorganic nitrogen (DIN) and dissolved organic nitrogen (DON); TDP can also be divided into dissolved inorganic phosphorus (DIP) and dissolved organic phosphorus (DOP).This study, which focused on the composition of DOP, employed ultrafiltration to separate DOP into low molecular weight-DOP (LMW-DOP) and high molecular weight-DOP (HMW-DOP). The concentrations of DIN and DON accounted for 75 ± 9 %、25 ± 9 % of the TDN, respectively. The monthly average concentrations of DIN and DON were 109.7 ± 37.2μM and 34.11 ± 9.4μM. The monthly average concentration of TDN was 143.8 ± 39.2μM; The concentrations of DIP and DOP accounted for 34 ± 12% : 66 ± 12% of the TDP, respectively. The monthly average concentrations of DIP and DOP were 0.083 ± 0.028μM and 0.17 ± 0.07μM, respectively. The monthly average concentration of TDP was 0.26 ± 0.083μM. Regarding the fluxes, the TDN (354 mmol m-2 yr-1), DIN (245 mmol m-2 yr-1) and DON (108 mmol m-2 yr-1), respectively ;
The fluxes of TDP, DOP and DIP were 927 µmol m-2 yr-1, 648 µmol m-2 yr-1 and 279 µmol m-2 yr-1, respectively. In order to discuss the contribution of atmospheric wet deposition to new production in the regional sea, this study improves that didn’t consider the difference in bioavailability of different molecular weights of organic phosphorus in the past study(>1 kDa，C/P：134；<1 kDa，C/P：106). This phosphorus flux can be converted to 3297 mg C mg m-2 year-1 and the nitrogen was converted to 24833 - 30872 mg C m-2 yr-1 that fixed by marine phytoplankton. That would account for 4.7% and 35 - 44% of new production by P and N in the southern ECS annually, which is taken to be 70372 mg m-2 year-1 based on the particulate organic carbon export fluxes.
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