摘要
全球藻礁的生物多樣性研究幾乎沒有。桃園觀音新屋海岸有全臺灣面積最大且最完整的藻礁分布，本研究沿海岸設立四個樣區，由南往北分別為新屋鄉新屋溪口、大潭電廠、觀音鄉觀音海水浴場和大園鄉樹林子海濱，於2012年9月至2013年6月間分4季進行調查。各樣區設立兩條垂直於海岸之穿越線，測量環境因子並進行藻類、底表動物、底內動物、魚類及鳥類的採樣調查，以量化藻礁生物多樣性。新屋溪口（15.78%－34.24%）與大潭電廠（13.76%－43.88%）大型藻覆蓋率高於觀音海水浴場（0%－0.53%）與樹林子海濱（0%）。底表動物、底內動物、魚類及鳥類的物種豐富度皆以大潭電廠最高，樹林子海濱最低，顯示樹林子海濱藻礁生態系已嚴重劣化。與觀新藻礁過去研究結果比較，本研究涵蓋生物多樣性範圍較廣，所量化之動物密度亦高出許多，說明過去研究明顯低估藻礁生物豐度。各研究彼此間相似物種不多，說明現階段仍低估了藻礁生物多樣性，可能還有許多物種尚待發現。若與其他海岸棲地物種與密度比較，藻礁物種與鄰近泥沙灘有很大差異，動物密度為高美濕地的5倍，香山濕地的8倍，其中藻類、刺胞動物、軟體動物、節肢動物與棘皮動物的物種多樣性較高，環節動物之物種數較少，但是環節動物與節肢動物的密度特別高，說明藻礁之生物多樣性與獨特性，亟需保育。建議可選取4種易於觀察的生物指標以監測藻礁狀況，包括：珠螺、草蓆鐘螺、花冠海燕與司氏酋婦蟹。
並列摘要
Research on the biodiversity of algal reefs is lacking globally. In Taiwan, the largest area of algal reefs is distributed along the coast of Taoyuan. In order to quantify the biodiversity, four sites were chosen for sampling, including Sinwu River (SW), Datan Power Plant (DT), Guanyin Beach (GY) and Shulinzih (SL). At each site, two transects were surveyed for the distribution and abundance of algae, epifauna, fish and birds in the four seasons from September 2012 to June 2013. In addition, a piece of reef (1000 cm3) was sampled at different elevation position (high, medium, and low) along the two transects at each site for quantifying infaunal abundance. The coverage of macroalgae was higher at SW(15.78%-34.24%) and DT(13.76%-43.88%) than that at GY(0%-0.53%) and SL(0%). The species richness of epifauna, infauna, fish, and birds was highest at DT and lowest at SL, indicating the degradation of algal reefs at SL. Compared to the previous studies in the algal reefs, our results comprised more taxa and the density was much higher, indicating that the previous studies underestimated the biodiversity of algal reefs. In addition, not many species overlapped among these studies, suggesting that some species were still unfound yet. Compared with other studies on other habitats along the coast of western Taiwan, the species and density of algal reefs differed greatly from others. The animal density was 5 times that on the Kaomei Wetland and 8 times that on the Hsiangshan Wetland. In particular, the biodiversity of algae, Cnidarians, molluscs, arthropods, and echinoderms was higher, but the species richness of annelids was lower. The density of annelids and arthropods was also higher. These indicate that the biodiversity and uniqueness of algal reefs and the need of urgent conservation. Finally, based on our study, 4 indicator species were suggested for monitoring the health of the algal reefs, including Lunella coronate, Monodonta labio, Asterina coronate, and Eriphia smithii.