屏東湧泉濕地水質環境因子與淡水軟體動物群聚之關係

為了解淡水軟體動群聚分布與環境因子之間的關係，本實驗於2007年6月至2008年6月，於屏東縣萬巒鄉五溝水與屏東縣九如鄉玉泉之湧泉溼地，採集淡水軟體動物，計算其群聚指數 (community index) 、豐度 (abundance) 與生物量 (biomass) ，並進行水質分析，測量環境因子中，包含物理因子雨量 (rainfall) 、水深 (depth) 、水流速 (velocity) 、水溫 (water temperature) 、濁度 (turbidity) 與懸浮固體 (Suspended solids , SS)；化學因子溶氧量 (dissolved oxygen, DO) 、酸鹼度 (pH) 、生化需氧量 (biochemical oxygen demand, BOD) 、化學需氧量 (chemical oxygen demand, COD) 、氨氮 (ammonia) 、亞硝酸鹽 (nitrite) 、硝酸鹽 (nitrate) 、磷酸鹽 (phosphate) 、硫酸鹽 (sulfate) 與硬度 (hardness)，之後以主成分分析、皮爾森相關係數與判別分析，分析物種群聚與環境因子之關係。結果發現淡水軟體動物10科17種，共9779隻。其中前6大優勢物種依序為石田螺 (Sinotaia quadrata) 、梯形福壽螺 (Pomacea scalaris) 、瘤蜷(Tarebia granifera) 、台灣網蜷(Melanoides tuberculatus formosensis) 、網蜷 (Melanoides tuberculatus tuberculatus) 與福壽螺 (Pomacea canaliculata) ，多樣性指數以崇蘭新圳最高 (H’ =1.87) ，佳平溪主流最低 (H’ = 1.09) 。主成分分析 (Principle component analysis, PCA) 共萃取出六個主成分，累積解釋量為71.91 %，影響較大的因子為氨氮、磷酸鹽、硫酸鹽、酸鹼度與硬度。皮爾森相關係數 (Pearson’s correlation coefficients) 方面，豐度與酸鹼度、硫酸鹽及硬度成正比；生物量與溶氧量成反比，但與也酸鹼度、硫酸鹽及硬度成正比。最後，以判別分析 (discriminant analysis) 分析，前6大優勢物種與環境因子之關係，並找出各物種主要受到哪些環境因子的影響，進一步討論以淡水軟體動物為水質指標生物的架構。

關鍵字

溼地；淡水軟體動物；環境因子；指標生物

並列摘要

In order to studied the relationship between freshwater mollusk communities and environmental factors, the freshwater snails were collected and their abundance, biomass, Shannon-Wiener index (H’), Pielou's evenness index (J’) and richness were calculated, from June 2007 to April 2008 in Wugoushuei and Yuciyuan in Pingtung. Furthermore, we measured environmental factors such as depth, velocity, rainfall, DO, pH, BOD, COD, ammonia, nitrite, nitrate, phosphate, sulfate and hardness. We used principle component analysis (PCA), Pearson’s correlation coefficient and discriminant analysis to elucidating the relationship between freshwater mollusk communities and environmental factors. There were 10 families, 17 species, 9779 freshwater mollusks collected in this study. The dominant species were Sinotaia quadrata, Pomacea scalaris, Tarebia granifera, Melanoides tuberculatus formosensis, Melanoides tuberculatus tuberculatus and Pomacea canaliculata in order. The highest H’ was in Chonglan new channel (1.87) and the lowest was in Jiia Ping river (H’ = 1.09). There were six components extracted by principal component analysis (PCA). According to Pearson’s correlation coefficient the abundance and biomass were significantly positively correlated with pH, sulfate, hardness, but biomass was significantly negatively correlated with rainfall. Finally, we used discriminant analysis to establishment biological indicator by freshwater mollusks.