博士 / 中國文化大學 / 地學研究所 / 87 / According to the historical documents of Holland and Chin Dynasty, the coastal landform of Southwestern Taiwan is characterized by liman coast, which was marked by lagoons and offshore bars. Lagoons of Peikang, Wenkang, Taofengkang, Taichiang, Yaokang and Takukang are along the coast from Yunling to Kaohsiung in 17th century, the total areas is about 615 km2. Then lagoons have been filled up and reclaimed as fish ponds and salt pans due to rapid sedimentation in the typhoon seasons over the past three hundred years, landform changes in this areas are notable. This study focuses on coastal plain from Peikang-chi to Kaoshiung devoting to the most observable landform changes of coastline, sand dune and river channel. Based on reviewing documents, aerial photo interpretation, field excursion, map work, data analysis, the conclusions are obtained. The result presented that tectonic uplifting of foothill, river terrain, high river loading and changeable climate regime, are the most important physical factors to influence landform changes. In contrast, the human activities influenced landform changes such as expansion of settlements, construction of irrigation canals and dams, reclamation of tidal flat and straightening of river channel. There are some spatial variations of landform changes between north and south sections. Landform changes in the nothern section seem to be more notable than southern ones. Because of Pachang-chi and Tsengwen-chi were avulsed five and four times from north to south, and the shifting range is about 20 and 25 km, however, the channel was confined after the dyke had been constructed in 1920s. The coastline has prograded westward, however, the west coast of offshore bars have been eroded with a maximum rate of 12m/yr in average. In addition, the offshore bar migrated landward, such as Waishanting Bar moved in SE orientation toward the land with a rate of 51 m/yr from 1904 to 1990. Responding to the abundant sand supply from Choushui-chi and Tsengwen-chi, sand dunes distributed mainly in Peikang and Tainan coastal plain. Most of the sand dunes decreased in altitude caused by human modification, however, Luerhmen sand dunes have been increased due to the continuous sediments supply from the river mouth of Tsengwen-chi. Landform changes of this area have exerted some impacts on people''s life, such as the decline of ship ports, the threat of flood, the change of landuse, the damage of sand storm, the controversy of land ownership, etc. Obviously, the landform changes and human behavior have been interrelated closely to each other over last three hundred years. Overall, the landform changes of coastal plain in Southwestern Taiwan were caused by long term physical processes, but modified strongly by human agency in the recent time. Since land resources in Taiwan are limited, coastal plain in Southwestern Taiwan is valuable.
| Identifer | oai:union.ndltd.org:TW/087PCCU0141014 |
| Date | January 1999 |
| Creators | Han-Lin Chen, 陳翰霖 |
| Contributors | Jui-Chin Chang, 張瑞津 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 193 |
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