近年來利用海岸邊的植被如紅樹林作為海岸防護材料十分常見，利用植被來禦潮除了可能具有防災效果外，尚可帶來生態服務，是一種典型的自然解決方案(NBS)。對植被消波作用造成影響的有很多因子，可分為波浪條件(入射波高、週期)、地文環境(水深、海灘坡度)以及植被特徵(植被種類、密度、寬度、高度)等。
本研究使用XBeach非靜水壓模式對波浪傳遞經過紅樹林植被後的減衰情形進行模擬研究，探討幾個重要因子對紅樹林消波的影響。為貼近現況，本研究在模式中建立仿紅樹林特徵之植被模型，分別對根部、莖幹和枝葉的特徵進行參數化設定。本研究探討的影響因子包含有波浪條件(給定規則波和不規則波的波高和週期以及設計波浪條件)、植被特徵(包含紅樹林植被區寬度和密度)，以及地文環境和植被的無因次化參數，即植被和水深之相對高度(稱為相對高度)，各條件的模擬結果以無植被情況為對照組進行比較，並採用波高衰減率(R)和單位植被之波高衰減(r)以量化波浪通過植被之衰減程度。
由本研究模擬結果發現，紅樹林對波浪的衰減作用十分顯著，波高衰減率(R)在無紅樹林時皆小於3 %，有紅樹林時皆在40 %以上且最高可達92 %。在本研究探討的影響因子中，推斷紅樹林植被寬度對消波作用的影響程度最大。而在對波浪條件的分析中發現，入射波高越大和波浪週期越長則波浪衰減越多，並且入射波高對紅樹林消波的影響較大。波高衰減至一半時的位置皆在植被區域約30 %內，表示波浪在紅樹林前段的衰減速度較快。

Coastal vegetation such as mangrove forests can be a prominent costal engineering application of attenuating wave energy. They can also bring lots of advantages including ecosystem services, economic values and environmental protection.
As wave propagate through coastal vegetation, the height and energy of the waves will lose. Wave reduction in vegetations depends on many factors: hydrodynamic conditions, vegetation characteristics and environmental factor. The influences of each factor are important for the management of the mangrove area.
This thesis aims to identify the effect on wave reduction by each factor includes incident wave height, wave period, vegetation width, vegetation density and the relative height of vegetation height and water depth. The investigations are carried out using 1-D XBeach numerical model non-hydrostatic mode by setting mangrove into 3 layers vertically from bottom to top. The layers are divided as the roots, stem and the canopy where there is vertically significant for mangroves. The study focuses on the wave height variation in mangrove area with use of wave reduction ratio (R) and average wave reduction per m (r).
Results show that the attenuation of wave height by mangroves is significant. R is above 40% and up to 92% in all cases with mangroves, and less than 3 % in cases without mangroves. 50% of the wave height is attenuated in the first 30% of the mangrove area indicating that the wave attenuates faster in the forepart of mangroves. From the analysis of wave factors, the efficient attenuation of waves is related to incident wave height and wave period. From the analysis of vegetation characteristics, when the mangrove width, density and relative height increases, the wave attenuates more.

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