Effects of Ecological Restoration for Habitat Selection of the Cobitis sinensis at Jie-Mei Spring Channels

• Main Authors: Yin-Wan Chung, 鐘尹婉
• Other Authors: Wen-Lian Chang
• Format: Others
• Language: zh-TW
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/65061207198107336208

碩士 === 臺灣大學 === 生物環境系統工程學研究所 === 98 === The development of agricultural canals not only pursues the convenience of irrigation but also promotes the importance of ecological engineering. As a result, fishes, shrimps, crabs, shellfishes and vegetation can restore and survive in agricultural canals. Jie-Mei Spring canal, attached to Miaoli irrigation associations, has broadened channel, at the first stage of ecological engineering (left canal). Creating pools and setting stone pitching to retard velocity. The construction is to provide a habitat for Cobitis sinensis to feed, reproduce and avoid predators. Through the field investigation in May and July in 2009, the left canal is compared to the right canal which doesn’t implement ecological engineering. The left canal has lower flow velocity, deeper depth and more Cobitis sinensis. The results show the benefits of ecological corridor among canals and fields. After field investigation, water quality and soil of the experimental analysis, it can be found Cobitis sinensis prefers environment where are abundant of deep pools, grass ditches and sand. On the other hand, Cobitis sinensis avoids in run, riffle and loam. Twelve water quality variables are combined into a data matrix and subjected to the factor analysis. Three principle components are extracted as nutrient factor, salinity factor, and photosynthesis factor. The results demonstrate that Cobitis sinensis distributes in middling nutrition, low salt, abundant sunshine and vegetation-covered area. The experiment results in lab shows that base-substance is useful to resist velocity for Cobitis sinensis. Gravel (4.70-12.70mm) is a best base-substance to support Cobitis sinensis swimming in this experiment. The critical swimming speed arrives 0.43m/s. Male Cobitis sinensis’s strength and shape of pectoral fin has more advantages to resist water velocity than female. Angles of the body (such like head, pectoral fins, dorsal fin) decrease as the flow rate increases.