蘭陽溪上游集水區降雨量之趨勢分析

Trend Analysis of Precipitation in the Lanyang River Upstream Watershed

宋健豪(Jian-How Sung) ； 廖俊瑋(Chun-Wei Liao) ； 廖學誠(Shyue-Cherng Liaw)

《中華林學季刊》 47卷4期 (2014/12) Pp. 341-357

摘要

近年來由於氣候變遷造成降雨特性逐漸改變，衝擊到集水區水土資源，因此，降雨特性分析已日益重要，不論是對生態保育或國土防災而言，瞭解氣候變遷下降雨趨勢的改變是基本且必要的。蘭陽溪集水區位於台灣東北部，全年有雨、時有水患，在治山防洪上應以長期的降雨量變化趨勢作為規劃基礎。本研究主要目的即是應用Mann-Kendall趨勢檢定，探討蘭陽溪上游集水區降雨量的變化趨勢，降雨量資料取自水利署雨量站，並透過克利金空間內插法計算整體集水區降雨量。研究結果顯示，海拔較高之南山地區年降雨量、豐水期降雨量、枯水期降雨量及年最大日降雨量均呈現顯著的增加趨勢，海拔較低之土場地區年降雨量則無明顯變化，但枯水期降雨量顯著減少、年最大日降雨量顯著增加，另外，透過克利金空間內插法所計算整體集水區降雨量則無顯著變化趨勢。

關鍵字

蘭陽溪上游集水區 ； 降雨型態 ； M-K趨勢檢定 ； 克利金空間內插法

並列摘要

The trend analysis of precipitation is very important for disaster prevention and mitigation under the climate change condition. This study aimed to detect the trend of precipitation of Lanyang river upstream watershed applying the Mann-Kendall trend analysis. Furthermore, Kriging spatial interpolation was also used to calculate the precipitation of whole study area. The results showed that the trends of precipitation including the annual, wet seasons, dry seasons and annual maximum daily precipitation were significantly increasing in the Nan- Shan area with higher elevation. In addition, in the Tu-Chang area with lower elevation, dry seasons precipitation was significantly decreasing but annul maximum daily precipitation was increasing. However, the precipitation in whole study area based on the Kriging spatial interpolation had no significant change.

並列關鍵字

Lanyang river upstream watershed ； Mann-Kendall trend test ； rainfall pattern ； Kriging spatial interpolatio