碩士 / 國立臺灣海洋大學 / 海洋環境資訊系 / 106 / In this study, we collected and analyzed particulate aerosol samples from Dongsha Island, which is a remote island located north of the South China Sea (SCS). From April 2007 until March 2009, 240 total suspended particle (TSP) samples were collected over a 2-year period and were analyzed to examine the major ions and water-soluble nitrogen species. The concentrations of water-soluble ions in aerosols over the Dongsha Island show a strong seasonal variation which the relative high concentrations are found in northeast monsoon seasons (autumn to spring), and the low concentrations in southwest monsoon season (summer). The mean concentration of the water-soluble total nitrogen (WSTN) is 217±115 nmol m-3. The water-soluble inorganic nitrogen (WSIN) and water-soluble organic nitrogen (WSON) accounted for approximately 61±15% and 39±15% of the WSTN, with mean concentrations of 132±88 and 85±46 nmol m-3. The ammonium (NH4+) and nitrate (NO3-) accounted for 59±14% and 41±14% of the WSIN, with mean concentrations of 78.4±67.3 and 54.3±28.7 nmol m-3. The calculation results of molar ratios between NH4 and nss-SO42- reveal that the atmosphere over the study area suffer from heavy acidic ion species. The compound of sulfate in aerosol is probably in the form of NH4HSO4. Among all the inorganic species, sea salt (NaCl) is a major contributor to the water-soluble inorganic ions, the evaluation of Cl-/Na+ ratios in aerosols indicates a strong chloride deficient under the northeast monsoon seasons. Regarding the dry deposition fluxes, the NH4+ (2.5±2.1 mmol m-2 yr-1) and NO3- (21±11 mmol m-2 yr-1) accounted for 11% and 89% of the WSIN, respectively, and the WSON (27±15 mmol m-2 yr-1) and WSIN (23±13 mmol m-2 yr-1) accounted for 54% and 46% of the WSTN, respectively. Using the ratio of carbon and nitrogen in the Redfied ratio (6.625), we estimated that the new production at Dongsha Island (0.52~0.81 mmol C m-2 day-1) which can contribute 5.58~8.74% of new production in the surface water of northern South China Sea (9.24 mmol C m-2 day-1).
| Identifer | oai:union.ndltd.org:TW/106NTOU5276005 |
| Date | January 2018 |
| Creators | Huang, Shih-Zhe, 黃士哲 |
| Contributors | Chen, Hung-Yu, 陳宏瑜 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 95 |
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