Coastal Wetland Monitoring and Evaluation with Multitemporal Remote Sensing Images

• Main Authors: Shu-mei Yu, 尤姝媚
• Other Authors: Ming-chee Wu
• Format: Others
• Language: zh-TW
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/75062240016348963525

碩士 === 國立成功大學 === 衛星資訊暨地球環境研究所 === 97 === “Monitoring” and “Evaluation” are the two fundamental work for environmental protection and management. Wetland is an ecosystem between the water and the land with multifunctional capability such as “high primary production” and “high carbon sequestration”. The net primary production of a coastal wetland is much better than any other kinds of oceanic system; namely, as to how the monitoring and the evaluation can be done sufficiently is very much significant. The proposed study area is set at Chi-Gu Coast, the largest wetland in Taiwan. The complex ecosystems include the sandbars and lagoon at the Chi-Gu estuary, and the north tidal land at Tseng-Wen estuary. The area is known for the habitat of the endangered water bird, Black-faced Spoonbills. The scope of work for the proposed study is to develop an effective methodology in monitoring and evaluating the environmental changes of coastal wetlands. Multi-temporal satellite mage process and Geographic Information System (GIS) are adapted to perform the measurement for environmental changes and spatial statistical analyses, such that to establish the Wetland Evaluation Indices (WEI) based on the remote sensing technique. By applying the vegetation and water indices, landcover classification, edge detection, and change detection technologies, the temporal and spatial dynamic changes for landform of the coastal wetland, surface hydrology, and vegetation coverage will therefore be numerically established in order to understand the elements of changes. According to the results, the on shore side beach of the three sandbars surrounding the lagoon were quickly being eroded; the sand body were then transported from the open-sea side and deposited at the inner-sea side causing the siltation of the lagoon. Health level of the windbreak forests was either degrading or dying, especially for those are located along the coastal regions at the front side of the western bank. Further more, due to the effect caused by the Offshore Breakwater, uneven deposition and erosion occurred along northern portion of the coastal regions of the western bank, namely, the windbreak forest of this section were disappearing quickly. The reduced biological habitat was due to the purposely elimination of the mangroves at the Chi-Gu estuary. Changes of sandbars, lagoon, and the vegetation for Chi-Gu area tend to have been degrading. Water shed area of the sanctuary for Black-Faced Spoonbills may be expanding to benefit the habitat for aquatic biology, it is suggested to notice that the rapid erosion along the northwestern side of the tidal land, for rapid soil erosion may destroy the shallow water environment. Besides the apparent seasonal deviation and spatial difference; rainfalls, typhoons, tides, distribution of vegetations, and human activities are the influential elements for the environmental changes within the study area.