應用三維水質模式探討高山湖泊水質受風剪應力之影響研究

APPLICATION OF THREE-DIMENSIONAL WATER QUALITY MODEL TO PREDICT WATER QUALITY CONDITIONS UNDER DIFFERENT WIND STRESSES IN THE SUBALPINE LAKE

林皓華(Hao-Hua Lin) ； 柳文成(Wen-Cheng Liu) ； 柳鴻明(Hong-Ming Liu)

《農業工程學報》 65卷3期 (2019/09) Pp. 22-36

https://doi.org/10.29974/JTAE.201909_65(3).0003

摘要

高山湖泊因地理位置偏遠，經常形成獨特生態系統並保有多種的特有物種，是重要的自然生態棲地。目前國內對於高山湖泊的研究，主要著重於基礎研究，鮮少有針對環境變化影響高山湖泊水質進行探討。本研究以三維水理及水質模式應用於模擬高山湖泊翠峰湖水理與水質狀況，以蒐集2010年1月至2011年7月的實測水位、水溫與水質資料進行模式之檢定與驗證，結果顯示模式模擬結果與實測數據相當吻合。模式經檢定與驗證後，應用於探討風剪應力對水質之影響，於模式應用中設定兩種模擬情境，分別為情境一（風速5.66m／s，風向東北風）與情境（風速20.0m／s，風向東北風），比較情境一與情境二之模擬結果顯示，風剪應力對翠峰湖表層流場、水溫與各水質濃度有顯著的影響。當風速增加時，氨氮、硝酸氮、溶氧及葉綠素濃度降低，但總氮與總磷濃度則會增加。

關鍵字

水理 ； 水質 ； 翠峰湖 ； 三維數值模式 ； 風剪應力

並列摘要

Subalpine lakes often formed unique ecosystems and retained a variety of endemic species because there were geographically remote. Subalpine lakes are important natural habitats. Currently, researches on Taiwan's subalpine lakes focused on basic research. There were few researches to investigate the impact of environmental changes on the water quality of subalpine lakes. In this study, a simulation concerning the conditions of hydrodynamic and water quality of the Tsuei-Feng Lake, a subalpine lake, was conducted using a three-dimensional model of hydrodynamic and water quality. The calibration and validation of the model were conducted with the observational data (i.e., water level, temperature, and water quality) collected from January 2010 to July 2011. The results demonstrate that the simulation results reproduce the observational data. After model calibration and validation, the model was applied to investigate the influence of wind shear stress on the water quality. Consequently, two simulation scenarios were set in the model applications. Two simulation scenarios were Scenario 1 (wind direction: northeast wind and wind speed: 5.66 m/s) and Scenario 2 (wind direction: northeast wind and wind speed: 20.0 m/s). The simulated results indicate that wind shear stress has a significant influence on surface flow field, water temperature, and water quality of the Tsuei-Feng Lake. When the wind speed increased, the concentrations of ammonia nitrogen, nitrate nitrogen, dissolved oxygen, and chlorophyll α were decreased, and the concentrations of total nitrogen and total phosphorus were increased.

並列關鍵字

Hydrodynamics ； Water quality ； Tsuei-Feng Lake ； Three-dimensional numerical model ； Wind shear stress