| Summary: | 碩士 === 逢甲大學 === 水利工程所 === 95 === Natural streams, evolving with varying flow’s sediment carrying capacities, bed configurations and bank’s resistance to scouring, as well as incoming flows and sediment regimes, are constantly adjusting their bed morphology and their relationship with flow-sediment. Thus stream reaches of a river may present different stages of fluvial processes, but the river system will tend to reach a near-equilibrium state between erosion and deposition with these self-adjustments taking place. Classification of stream types of a river system therefore can help us understand the characteristics of a stable channel reach, and the balancing characteristics between incoming flow-sediment regimes, valley geology, and their interplay in general. The Gao Ping river watershed is used as a case study in this research. Through the analysis of the hydraulic and geologic data, in-situ data collection, and calculations of theoretical hydraulic geometric relation, and apply NETSTARS model, after state examining, sensitive degree identifying reckon it future the water reason parameter of the course of river, we classified stream reaches, investigated the rule of changes, and evaluated variations in bed composition and channel stability indices, inquire into its river bed stability degree and will change trend in the future etc. river characteristic. The research results are expected to provide guidelines for future studies in establishing indices in investigating regional stream characteristics and for quantifying fluvial processes.
This research with layering, is gone to small dimensions by the big dimensions the river to analyze its stable degree: Gao Ping river to belong to higher incises degree, the flat surface incises degree smaller, Follow the flood plain course of river that the distance mollifies for the slope, through Rosgen(1996) classification the rule analysis get Gao Ping river to belong to multiple cnannels and high width/depth a course of D type river, Longitudinal section’s belonging to a cave type channel and cross section have poor stability; Gao Ping river to rain concentration in summer, the discharge is big in a moment. Each classification method concert the an aerial map and scene photograph identification, and join model emulation to understand as a result future course of river possibility of turn into with stability situation, the results can also serve as reference for river restoration and watershed management.
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