- 期刊
氣候變遷對櫻花鈎吻鮭適當棲地之衝擊
The Climate Change Impact Assessment of Formosan Landlocked Salmon Suitable Habitat
摘要
本研究利用一物理性的水溫模式進行國寶魚櫻花鈎吻鮭棲地水溫的模擬，評估氣候變遷對於其生存棲地在時間與空間考量下，所可能產生的影響。由於台灣的地形特性，使得上游河川多蜿蜒於陡峻的山壁之間，因此國外發展之水溫模式，在沒有考慮地形遮蔽的效應下，將無法適用於台灣地區。本研究在櫻花鈎吻鮭棲地之一：高山溪流域進行水溫模擬，同時將地形遮蔽以及植生遮蔽之效應納入水溫模式的計算當中，使得模擬結果更為準確。在研究中利用CCCM、GISS、CGCM2以及HADCM3等「大氣環流模式」提供未來氣候變遷之下的氣候資料，進行未來氣候條件下的水溫模擬。研究結果指出，現況氣候條件下，一年當中僅7月之最高水溫會超過17℃，成為「不適當棲地」；此外，7月之「不適當棲地」長度僅約700公尺。但是在氣候變遷的影響之下，6、7、8三個月份之最高水溫都將超過17℃；且7月份之「不適當棲地」的長度，將增加到約1500~2200公尺。研究結果顯示櫻花鈎吻鮭的「適當棲地」，在時間與空間的尺度上，均有被壓縮的情形出現。
並列摘要
This study provides a physics-based model for predicting the climate change impact on stream temperature and in turn on Formosan Landlocked Salmon (Oncorhynchus mason formosanus) habitat. Because upstream watersheds in Taiwan are surrounded with high and steep mountains, the foreign water temperature models without consider terrain shading effect are not suitable for Taiwan. This study modeling one of the Formosan Landlocked Salmon's habitats: the GaoShan creek and consider both terrain and vegetative shading effect to provide reasonable simulation of water temperature. Projections based on the predictions of GCMs, including CCCM, GISS, CGCM2 and HADCM3 models, provided information on future climatic conditions, and then water temperature in the future can be predicted accordingly. According to the results, under current climate condition, the highest water temperature will be above 17℃ only in July, which causes length of the 700 meters of ”unsuitable habitat.” Under the future climate change impacts, the highest water temperature will be above 17℃ in June, July and August. Moreover, the length of the ”unsuitable habitat” will extend to about 1500 to 2200 meters. It indicates that under the impact of climate change, the suitable habitat for Formosan Landlocked Salmon will be compressed temporally and spatially.