碩士 / 國立臺灣大學 / 農業工程學研究所 / 88 / Abstract
Many wetlands undergo seasonal cycles in precipitation and water depth. This environmental seasonality is reflected in patterns of production of fish biomass that in turn influence the phenology of other components of the food web including wading birds. Human activities such as drainage or other alterations of the hydrology can exacerbate these natural cycles and results in detrimental stresses on fish production and the higher trophic levels dependent on this production. In this paper we model the seasonal pattern of fish production in a freshwater marsh, with special application to the Kuandu wetland located in the north Taiwan region. The model illustrates the temporal pattern production through the year, which can result in very high density of fish at the end of a hydroperiod （period of flooding）, as well as the importance of ponds and other depressions, both are refuges and sinks during dry periods. The model predicts that：（1） an effective threshold in the length of the hydroperiod that must be exceeded for high fish-population densities to be produced, （2）the large, piscivorous fish appear to have a major impact on smaller fish in the marsh habitats, and（3）the recovery of small-fish populations in the marsh following a major drought may require up to 1~2 years .
keywords：fish dynamics, hydrology, seasonal cycles, hydroperiod, wetlands
| Identifer | oai:union.ndltd.org:TW/088NTU00404028 |
| Date | January 2000 |
| Creators | Jeng-Wei Tsai, 蔡正偉 |
| Contributors | Chung-Min Liao, 廖中明 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 88 |
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