風沙現象研究－以苗栗苑裡海岸風沙為例

Aeolian Sand Phenomena-A Case Study of Miaoli Yuanli Shoreline

許盈松(Yin-Sung Hsu) ； 洪振豪(Chen-Hao Hung) ； 周湘俊(Hsiang-Chun Chou) ； 陳清茂(Ching-Mao Chen) ； 朱家興(Jia-Sin Jhu) ； 林大港(Ta-Kang Lin)

《農業工程學報》 52卷4期 (2006/12) Pp. 15-24

摘要

風沙現象是一複雜多變，且運動尺度範圍極大的自然現象，多發生於沙漠地區或沙岸發達之海岸地帶。因其物理現象觀察不易掌握，理論描述亦有侷限；故往往需要蒐集歸納研究區域之完整地文地貌條件與現地風沙觀測資料，普配合適當風沙運動模式，方能適當評估風沙運動尺度與活動趨勢。苗栗苑裡沿海皆爲海岸平原，海岸線平直、沙灘非常發達，並受東北季風衝擊。遇有強風則習沙群起，造成苑裡海岸地區每逢東北季風便吹起強烈的風沙，經年累積之沙丘甚至將鄰近房舍完全淹沒。本文針對風沙機制、風沙觀測方法進行回顧分析，並以苗栗苑裡海岸爲探討案例，評估探討風沙現象成因及機制、風沙觀測方法及風沙輸移公式適用性。研究結果顯示苗栗苑裡海岸風沙現象成因，並以Chepil輸沙公式推估量較接近觀測值。本文成果將有助於瞭解海岸風沙現象及運動機制，並可提供風沙觀測及輸移量推估研究及實務工作之參考。

關鍵字

風沙 ； 躍移載 ； 集沙效率 ； 輸沙量

並列摘要

The behavior of aeolian sand motion is characterized by complex mechanism and multiple mechanics characteristics scales existing in an erosion desert and along the sandy coasts of shoreline. It was difficult to describe the aeolian sand phenomena theoretically in detail without field data. Where the surface consists of fine sand in the Miaoli Yuanli shoreline, such as wind-blown sand phenomena is active driven by a strong wind in winter. The formation of sand dunes and wind-blown sand usually obscure the roads and buildings near the coast. There are some issues of the phenomena of aeolian and prevention method from blown sand has so far been forthcoming. Field measurements of wind velocity and blown sand were conducted and the results of that compared with several typical empirical formulas in this study. The MWAC catchments were adopted to estimate the flux of wind-blown sand. The present results show the process of aeolian sand and characteristics of blown sand in Miaoli Yuanli shoreline. It is concluded that the estimate of Chepil's formula is reasonable than that of other formulas in this study.

並列關鍵字

Aeolian sand ； Saltation load ； Trap efficiency ； Wind-blown sand flux