一、研究緣起
墾丁國家公園是台灣同時擁有陸域與海域的國家公園之一，亦是台灣海洋生物多樣性最高的區域之一。由於裙礁型的珊瑚礁位於離岸很近的淺水區域，容易受到污染物的加入而造成當地之生物群聚結構改變，故必須及早做長期性的監測與研究，以建立各項環境監測資料，才能瞭解環境變遷與生態改變的因果關係，並做為未來制定環境政策。
二、研究方法及過程
針對墾丁國家公園海域長期監測樣點進行水質環境監測，每季執行水質監測取樣及分析數據。監測項目包含水溫、鹽度、酸鹼值(pH)、溶氧、濁度、水中懸浮固體、生化需氧量、氨氮、硝酸鹽、亞硝酸鹽、磷酸鹽、矽酸鹽、葉綠素甲、弧菌數等。採樣方式採環保署公告之檢驗方式。統計歷年相關資料及分析水質變動與環境相關影響。
三、重要發現
本年度海域測站水質參數之相關性分析矩陣表顯示，鹽度與BOD5、營養鹽(NH3-N, NO3-N, NO2-N, SiO2-Si)及vibrio呈現負相關，而BOD5、NH3-N與vibrio的正相關性，說明了海域測站鹽度受淡水輸入的影響(降雨、陸上逕流與排放溝渠等)，導致海域沿岸營養鹽與耗氧性物質及弧菌數量的增加。推測墾丁測站受廢水影響程度仍然最為顯著，其次為船帆石、香蕉灣與佳樂水測站。墾丁國家公園內主要河川之污染程度隨季節性而有所變化，分別介於未受污染至中度污染；而影響計畫所屬各河川之污染程度之污染積分主要為生化需氧量及懸浮固體量；歷年監測結果顯示，保力溪60%未受污染到輕受污染，40%中度污染到嚴重污染；石牛溪79%未受污染到輕受污染，20%中度污染及1%嚴重污染；港口溪78%未受污染到輕受污染，22%中度污染。海域測站歷年監測結果顯示，主要影響墾丁海域水質因子為營養鹽、鹽度及溶氧，其中鹽度呈負相關且與營養鹽呈正相關；而影響海域鹽度主要因素與自然氣候降雨有關，降雨造成表面逕流，導致近岸海域水質中的陸源營養鹽(硝酸鹽、矽酸鹽、磷酸鹽與氨氮等)增加。另外，反觀在非雨季及颱風季節的一般天候，結果顯示墾丁海域屬於環保署公告之甲類海域水質標準。
四、主要建議事項
持續監測墾丁國家公園海域沿岸水質變化：立即可行建議
主辦機關：墾丁國家公園管理處。
協辦機關：海洋生物博物館、東華大學海洋生物研究所。
墾丁近岸各項建設與遊憩人數增加，導致海域中陸源污染物質日益增多，對當地之海域生態及生物群聚造成相當的衝擊。本年度調查測站中，有些測站屬於海域遊憩區，海水水質在一般天候大多為優良等級，但在大雨、颱風過後水質易迅速惡化，大腸桿菌群、弧菌群等可能增加數百倍，讓水質變為「不宜親水活動」等級；因此，海域的水質衛生狀況極為重要。另外，海洋中幾種特殊的弧菌，如腸炎弧菌(V. parahaemolyticus)、霍亂弧菌(V. cholerae)與創傷弧菌(V. vulnificus)等，為常見的致病弧菌，與人類醫學或公共衛生息息相關，而越來越多的弧菌也發現具機會感染性(如：V. anguillarum、V. harveyi、V. mimicus與V. salmonicida…等)。弧菌科(Vibrionaceae)，廣泛分佈於海洋環境中且有廣泛的研究(Thompson et al., 2004, Eiler et al., 2006)，多存在於海洋、河口與水生生物體，在各種海藻和動物的組織或器官中也可檢測到高豐度的弧菌，例如鮑魚、雙殼類、珊瑚、魚、蝦、海綿、魷魚和浮游動物(Thompson et al., 2004)。在沿海生態系統中，弧菌科細菌數量極多，有時可佔海水總菌數的60% (Simidu and Tsukamoto, 1985)。其中有許多弧菌不但為魚蝦貝類的病原菌株，有些甚至對人類亦具致病性。過去文獻中，由於海水是副溶血性弧菌的天然棲息地，鹽度是副溶血性弧菌分佈的主要限制因素，海水高鹽度有助於副溶血性弧菌的生存和生長(Pradeep et al., 1984)。因此，廣泛的監測海水中弧菌數量的變化，可早期預警水質的變化，應持續進行監測採樣。
管控墾丁海域沿岸民宿高密度區域之生活廢水排放：中長期建議
主辦機關：墾丁國家公園管理處。
協辦機關：屏東縣政府環保局。
墾丁與南灣兩處設有污水處理廠，其接管率約8成，因位置偏僻或部分老舊建物無法接管，有的廢污水直接排入野溪，枯水期水不常流動，水質優氧化產生異味及藻華現象。因此，需加強宣導觀光事業環境生態保育與管理及廢污水排放標準，未經處理之都市與畜牧耗氧性廢水流經河床，各類污染物質蓄積於河床。雨季時，逕流即將土壤沖刷，將有機廢水經過溝渠或溪流輸送到海裡，造成黃濁的水質及營養鹽與微生物之增加，影響當地海域生態環境，相信對整個珊瑚礁之生物群聚已造成相當的衝擊。
計畫類別：[環境水文]
英文摘要：The Kenting National Park (KTNP), including the landmass area and nearshore waters, is located at the southernmost tip of Taiwan. The nearshore water region, supports one of the highest marine biological diversities within Taiwan. Most of the coral reefs in Taiwan are fringing reefs that are located in shallow areas near the coast; hence they are readily influenced by human activities. Coral reef ecosystems are interconnected given the lack of significant barriers to water flow in marine environments, and so if point-source pollution is documented at one site, it is possible that its detrimental influence may spread. Consequence, this project can find solutions for the impacts ofsewage discharge mentioned above on marine environments and to provide information for the authorities. The public can then be more concerned about the issues on environmental protection and ecological conservation, and the government can then take appropriate actions to manage the coastal environmental more effectively and to reverse the current deteriorating situation.
We collected seawater samples around the nearshore waters of KTNP from 19 different collection sites from Nov. 2017 to Jul. 2018. Immediately after collection, water samples were analyzed for hydrographical, chemical, and ecological parameters. Quality control for sampling equipment and for field measurement procedures, such as temperature, salinity, pH, and dissolved oxygen, were conducted following our governmental QA/QC regulations. The remaining water samples were preserved at 4℃ and returned to the laboratory for analysis of the following chemical and biomass parameters: temperature, salinity, conductivity, dissolved oxygen, pH, turbidity, total suspended solids, BOD5, ammonia nitrogen, nitrite, nitrate, phosphorus, silicate, chlorophyll a and vibrio. The QA/QC system includes a complete description of all the sample custody and chain-of-custody procedures, forms, documentation, and personnel responsibility necessary to ensure both scientific credibility and the legal defensibility of the data obtained from the samples involved in the project.
The Kenting station is impact significant by sewage discharge, followed Tsuan-Fan-Shir, Banana Bay and Gia-Lo-Shuei which mainly came from seasonal rainfalls and partially caused by typhoons. River pollution index (RPI) of the main rivers range from unpolluted to moderately polluted in KTNP. From 2001 to 2011 and 2013, the RPI of Bao-Li Stream is 60% unpolluted to negligibly polluted and 40% moderately polluted, to severely polluted；Shir-Neou Stream is 79% unpolluted to negligibly polluted and 20% moderately polluted to 1% severely polluted；Kang-Koi Stream is 78% unpolluted to negligibly polluted and 22% moderately polluted. The results of 2001~2011, 2013 show the main factors were nutrients, salinity and dissolved oxygen which negatively correlated of salinity and positively correlated with nutrient. The decrease of salinity was related with natural climate rainfall which runoff leads to increase nutrients (nitrate, Silicate, phosphate and ammonia nitrogen) in coastal waters.
KTNP is justifiably popular among both domestic and international tourists. However, increasing tourist numbers threaten to place an excessive burden on the natural environment by way of increasing coastal development, fisheries activities, sewage and other pollutant discharge, and consequent eutrophication. To prevent continual degradation of the coral reef environment, it is important to take a composite look at the potential factors that may cause harm to this fragile ecosystem. Herein, we introduce the impacts of humans activities on the coral reef ecosystems of KTNP as documented by kenting marine environmental monitoring program, with a special emphasis on water quality and the impact of increasing tourism, in order to draw greater attention to such threats. The excessive nutrients from the sewage, which also includes chemical fertilizers and pesticides used in local agriculture, eventually discharge into coastal waters during periods of heavy rainfall. The KTNP coral reef ecosystems are on an ongoing trajectory of degradation, as evidenced by regional patterns of coral and fish declines. Efforts to determine how seawater quality changes affect the coral reef environments of KTNP. As such, there is a need long-term collection data to monitor seawater quality within KTNP.
辦理單位：國立海洋生物博物館
計畫屬性：本處委託辦理
執行年度：106-107
計畫主持人：孟培傑
中文關鍵字：墾丁國家公園、營養鹽、河川污染指數
英文關鍵字： Kenting National Park, Nutrients, River pollution index