碩士 / 中興大學 / 生命科學系所 / 99 / Absence or redundancy of a certain nutrient in the water frequently limited the productivity of periphyton. This study measured periphyton productivity by recently developed microelectrode and the effect of nutrient limitation on periphyton productivity was investigated for the Wuling streams. Periphyton biomass was positively correlated with water DIN, impling agriculture fertilizer derived nitrogen input in the stream influencing periphyton growth. The highest periphyton productivity was measured in the midstream of the Cijiawan Stream in January and April, reaching 0.20 and 0.13 μmol [O2] mg[Chl a]-1 s-1, respectively. The lowest productivity of periphyton was observed in the Yusheng Stream which was greatly polluted by agriculture wastewater. In July and November, the highest productivity of periphyton was observed in the upstream of the Cijiawan Stream (0.25 and 0.22 μmol [O2] mg[Chl a]-1 s-1). Cyanobacteria was the dominant component in periphyton assemblage, comprising 58 % of the total abundance. Cyanobacteria were composed by Oscillatoria spp.and Chroococcus spp.. Light was the primary factor influencing algal community structure.
Potential of nutrient limitation couldn’t be simply predicted by water N:P molar ratio appropriately, and nutrient limitation was found to occur in all seasons. Occurrence of nutrient limitation was influenced by algal community structure. Nitrogen limitation occurred at the site dominated by filamentous cyanobacteria. Due to the high nutrient concentrations in the water, no nutrient limitation was observed in the Yusheng Stream. Light was the major factor limiting periphyton growth in high canopy cover environment, causing the abscence of nutrient limitation. The periphyton growth was mainly nitrogen limited in the Cijiawan Stream, where is the habitat of Oncorhynchus masou formosanus. Therefore, inputs of fertilizers and sewage pollutant should be monitored and prohibited. Buffer zone and vegetation recovery in riparian area should be established. In order to maintain water quality and avoid algal bloom, which may lead to deterioration of the stream water.
| Identifer | oai:union.ndltd.org:TW/099NCHU5105088 |
| Date | January 2011 |
| Creators | Chung-Ming Yeh, 葉峻銘 |
| Contributors | Hsing-Juh Lin, 林幸助 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 109 |
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