【學術亮點】Impact of Vegetation Roots on Erosion Protection of Sandbars in Laboratory Experiments
Ecological Agriculture: Nature-based Solutions for Restoring Ecological Landscapes on Degraded Hillslopes due to Extreme Climate Events【Department of Soil Water Conservation / Chen, Su-Chin / Distinguished Professor】
生態農業：自然解方修復極端氣候退化坡地之生態地景【水土保持學系/陳樹群特聘教授】
| 論文篇名 | 英文：Impact of Vegetation Roots on Erosion Protection of Sandbars in Laboratory Experiments 中文：植被根系對沙洲抗蝕效應之影響：水槽實驗研究 |
| 期刊名稱 | CATENA |
| 發表年份,卷數,起迄頁數 | 2025, 249, no.108631 |
| 作者 | Li, Jin-Fu; Chiu, Yen-Yu; Chen, Su-Chin(陳樹群)* |
| DOI | 10.1016/j.catena.2024.108631 |
| 中文摘要 | 河川地貌學研究除傳統著重的地質與水文因素外，植物群落亦在河道演變中扮演關鍵角色。本研究透過一系列動床水槽實驗，探討不同根系型態之植被對河道沙洲抗蝕性的影響。實驗設置三種沙洲類型：僅含石英砂粒之鬆散沙洲、覆蓋軸根型植被之沙洲，以及覆蓋鬚根型植被之沙洲，並在未浸沒、部分淹沒及完全淹沒三種水文情境下進行試驗。結果顯示，植被根系能有效提升土壤凝聚力，降低水流沖刷所造成的侵蝕。鬚根系在沙洲表層形成網狀結構，可於低流量下減緩外部侵蝕；軸根則透過強韌的主根與側根，在沙洲內部建立堅固支撐，有效抵禦高流量時的內部淘刷。與鬆散沙洲相比，覆蓋植被的沙洲在未浸沒、部分淹沒與完全淹沒條件下，分別展現出 24%、121% 與 222% 的抗蝕提升幅度。綜合而言，隨流量增加，植被根系所提供的保護效益亦隨之增強，其中在完全淹沒情境下，植被對沙洲穩定性的貢獻最為顯著。 |
| 英文摘要 | Studies of fluvial geomorphology should consider the essential roles played by plant communities, in addition to the usual geological and hydrological factors. Mobile-bed flume experiments were undertaken to investigate the effects of vegetation roots on the protection of sandbars from erosion in fluvial channels. Loose sandbars (i.e., containing only sand) and sandbars covered with taproot and fibrous-root vegetation types were used to assess the influence of vegetation on residual sandbar volume and channel erosion in the case of emergent, partly submerged, and submerged sandbars. Results indicate that vegetation roots effectively increase soil cohesion, reducing flow scouring. Fibrous root systems form a root net around sandbars, preventing morphological damage caused by external erosion at low flow rates. Taproots develop solid erosion-inhibiting structures within sandbars through their strong primary and lateral roots, effectively preventing internal scouring at high flow rates. Relative to loose sandbars, vegetated sandbars were 24 %, 121 %, and 222 % more protected from sediment erosion under emergent, partly submerged, and submerged conditions, respectively. The ratio of effective erosion protection increased with increasing discharge, with vegetation roots playing a key role in stabilizing sandbars, particularly under submerged conditions. |
| 發表成果與本中心研究主題相關性 | 本研究以動床水槽實驗探討不同植被根系型態對沙洲抗蝕性的影響，指出鬚根與軸根能分別在低流量與高流量情境下提升土壤凝聚力並減緩沖刷。其研究成果與永續農業創新發展中心的研究主題高度相關。首先，在「生態農業」領域，該研究屬於自然解方(nature-based solutions)的應用，提供河岸與流域復育的重要科學依據，有助於推動以植被改善水土保持的策略。其次，沙洲穩定與泥砂減量能間接保存土壤有機質並促進碳匯，呼應中心「科技農業」與「碳管理」的研究方向。此外，研究所揭示的根系結構作用機制，可延伸應用於「循環農業」及「新穎材料」領域，例如利用植物纖維或人工根網作為河岸補強技術。整體而言，該研究不僅在基礎科學上補充了植被—水流—地貌交互作用的理解，也可為中心跨領域研究提供重要切入點，支持農業與環境的永續發展。 |
