以Budyko架構探討氣候變遷與人為活動造成臺灣北部逕流量之變化

Evaluating the Impact of Climate Change and Human Activities on Streamflow Variations Based on the Budyko Framework in Catchments of the Northern Taiwan

李忠勳(Chung-Hsun Lee) ； 葉信富(Hsin-Fu Yeh)

《農業工程學報》 66卷2期 (2020/06) Pp. 26-42

https://doi.org/10.29974/JTAE.202006_66(2).0003

摘要

近年來氣候變遷與人為活動對環境的影響受到廣大的重視，而水文環境與水資源的利用息息相關，因此重新評估水資源可利用性與其危機具有相當的必要性。本研究首先以統計方法分析臺灣北部流域河川逕流量的變化趨勢與轉折點，其中包括蘭陽溪、基隆河、大漢溪、鳳山溪、油羅溪以及上坪溪。另外本研究採用Budyko-Fu模式與Budyko-Mezentsev-Choudhury-Yang模式評估氣候與流域特徵之彈性係數，可提供逕流量對降雨量、潛勢能蒸發散量、流域特徵參數之敏感度分析，並區分氣候變遷人為活動對逕流量造成影響之改變百分比。結果顯示，蘭陽溪與基隆河流域之流量分別於1993年與1990年檢測出轉折點，由Budyko型彈性係數法評估其改變因子，蘭陽溪流域流量於變化期增加32.50%，其中有約109.00%為非氣候因子造成；基隆河流域則於變化期減少18.11%之流量，主導因子為氣候變遷，約佔之71.53%減少量。敏感度分析結果指出臺灣北部分析的6個流域中流量皆以對降雨量變化的反應最大，每增加1%的降雨量，將使流域增加1.05%至1.37%之河川逕流量。本結果將可作為臺灣北部流域日後在擬定水資源及土地管理方針時定量化的參考。

關鍵字

逕流量 ； Mann-Kendall趨勢檢定 ； Budyko架構 ； 臺灣北部

並列摘要

Recently, the influences of climate change and human activities on global environment have been widely concerned. As the hydrological environment is intimately related to the water resources, it is essential to evaluate the water availability and related issues. This study applies statistical methods to analysis the streamflow data trend and break point in the basins of the northern Taiwan, including Lanyang River, Keelung River, Dahan River, Femgshan River, Youluo River and Shangping River. Furthermore, the Budyko-Fu equation and the Budyko-Mezentsev-Choudhury-Yang equation are applied to evaluate the elasticity coefficient of climate and catchment characteristics parameter, which can provide sensitivity analysis of streamflow to rainfall, potential evapotranspiration and catchment characteristic parameter, and quantifying the streamflow change due to the impact of climate change and human activities. The results show that the break points of streamflow data in Lanyang River and Keelung River were detected in 1993 and 1990 respectively. The streamflow of Lanyang River increased by 32.50% during the impacted period, about 109.00% of the variation was caused by non-climate factors; the Keelung River was reduced by 18.11% during the impacted period, and the dominant factor was climate change, accounting for 71.53% of reduction. Result of Sensitivity analysis showed that precipitation changes was the most sensitive factor of streamflow variation. For every 1% increase in precipitation, the streamflow would increase by 1.05% to 1.37%. These results could serve as reference for the sustainable development of water resources and territorial policies in the northern Taiwan.

並列關鍵字

Runoff ； Mann-kendall trend test ； Budyko framework ； Northern taiwan