| 摘要: | 湄公河是世界上第十二大河。河流源頭於中國，中間流經Myanmar、Lao PDR、 Thailand、 Cambodia， 最後流進越南匯入南中國海。湄公河流入越南境內後，分為兩 條支流，分別為東北側的Tien River 及西南側的Hau River。兩條支流又有許多小的支流 共同匯集產生湄公河三角洲，或稱Cuu Long 三角洲(越南語)。湄公河三角洲面積大約 為49520 平方公里，且涵蓋13 個省份，是亞洲最大的三角洲之一。湄公河最大的優勢 在於優渥的土地，對於經濟的發展有著重要的地位，特別是經濟作物的發展。 最近幾年自然的災害日益嚴重，如水災、旱災與山崩，這些災害使自然環境與生 活環境遭受到嚴重的破壞。其中又以Hau River 及 Tien River 河岸的變遷最為嚴重。此 外此區的人為影響十分嚴重。本研究利用1972 年、1989 年、以及2002 至2005 年的 Landsat 衛星影像分析，並且應用遙測及GIS 的技術去偵測於1972 年、1989 年、2000 至2005 年、以及1972 年至2005 年間Hau River 及 Tien River 河岸的變遷。除此之外， 本研究找出河岸變遷的主要原因，並且提出對於河岸兩側的主要防護工作。The Mekong River is the world’s twelfth largest river. It starts from China and flows through Myanmar, Lao PDR, Thailand, Cambodia and ends in the South China Sea in Vietnam. Coming to Vietnam, the river is naturally divided into two main streams; Hau River and Tien River, and a series of canals are also originated from these two rivers, this creates here a large delta with name “the Mekong Delta” or “the Cuu Long Delta” in Vietnamese language. The Mekong Delta in Vietnam is one of the largest deltas in Asia with area of around 49,520km2, and covers thirteen provinces. It has advantageous position, plentiful natural resource, and keeps important role for developing economy both region and nation, especially crop product and aquiculture. However, in recent years, people here have to resist natural disasters as flood, drought, and landslide, these make environment and life of the region changed seriously. One of the causes of the disasters is riverbanks change of Tien and Hau river as land erosion and accretion that are influenced by both natural process and man-made activities. This study used Landsat satellite images of years 1972, 1989, and of years from 2000 to 2005, and Remote sensing & GIS techniques to detect changes of riverbanks of Tien and Hau river in periods; 1972 – 1989, 1989-2000, 2000- 2005, and 1972 - 2005. In addition, the study found main reasons and effects of land erosion and accretion in these rivers, and also carried out remedies for riverbanks protection works. |
