都歷沿海集水區治山防災工程適宜性探討

台東地區自然環境特殊，使崩塌、地滑及土石流等天然土砂災害頻傳，危害當地居民、遊客生命財產安全及地方經濟建設造成莫大損失，也阻斷了對外的交通聯繫。而山坡地超限開發利用，遭嚴重破壞，失去自然平衡能力，再加上地震頻繁，颱風挾帶豪雨侵襲，致山洪暴發，山崩地滑，表土沖蝕流失，砂石淤積河道，造成嚴重災害。本調查研究係以台東縣成功鎮都歷沿海集水區所進行之治山防災工程，為主要探討對象，藉由工區立地環境因子與屬性基本資料、使用治山防災工法整治之現況和特性、邊坡及基礎設施破壞受損誘因與特性，以及邊坡穩定治理成效、改善措施與因應對策等進行調查分析及整治工法適用性比較與成果效益評估，篩選出適合於都歷沿海集水區之治山防災整治工法與植生復育生態工法運用之參據及治理模式。經綜觀41處工程樣區實勘調查，彙整歸納歷年來各工區使用治山防災整治工法之適用性進行優劣點比較分析及效益評估結果，得知為穩定坡面及溪床，防止大量土砂下移，以及抑止土砂災害上，就工法成效表現而言以場鑄混凝土基礎工配合砌石工之縱向保護工處理最為佳，但縱向保護工法之砌石工，須於適當間距設置固床工保護，以防砌石工護岸破壞時，造成連鎖效應導致全面潰決；而縱橫向構造物必須搭配使用，才能使構造物安全，以避免縱橫向侵蝕破壞，尤其在基腳穩固處理方面，則有互補之功能。而防砂設施工法以採用滯洪沉砂池，為本區急迫需要設置工程設施，可減少土砂下移及洪峰流量。坡面植生工法配合覆土撒播或噴植工法及栽植草苗與苗木栽植，以加強緩衝綠帶植生，在本區域使用最為適宜且最有效的治理工法，除可達保水固土、邊坡穩定之成效外，更可促進當地植生綠化早日演替。近年來天氣極端異常，經常會有超大豪雨的出現，其對治山防災工程是一大考驗，經國內外近幾年之災情分析，此現象已非人為設施所能承受，僅能採硬體方面之工程減災，另輔以軟體方面之疏散避難，軟硬兼施方式進行，以確保人民生命與財產安全及國土保安之目的。

關鍵字

治山防災；滯洪沉砂池

並列摘要

Natural environment in Taitung is special, making the natural soil sand disasters keep pouring in such as collapse, ground slippery and mudslides. They endanger local residents, visitor's security and economic construction in the place of the life property to cause great loss, also stop outward of the transportation contact. And due to the overdeveloping exploitation of slope ground,which encounters severity break and loses a natural equilibrium ability, Also,earthquakes are multifarious,typhoon carry pouring rain to encroach upon, with the result that swollen mountain stream delivers suddenly and violently, landslide and ground slippery, the topsoil washes eclipse to run off, the freestones silts up courses of river, causing serious disasters. This investigative research with success Township in Taitung County is based on Duli coast watershed carrying on its watershed management and erosion control methods, in order to mainly inquire into the object, by the work area of environmental factors and attributive data, using the work method of preventing disasters by regulating mountain,of current conditions and characteristic, side ascent and infrastructure break damaged inducement and characteristic, and the side ascent stability manage result, improve measure and respond counterplans to carry on investigation analysis and the work method applicability comparison to evaluate with result benefits, sieveing suitable references and manage mode for Duli coast gather water area of a mountain disaster prevention renovation work methods and plants regrow ecosystem. Through taking a comprehensive view of 41 engineering sample area, the area investigates inquisition actually, compling through the years towards each work area's usage of curing work method of mountain disaster prevention of applicability to carry on good and bad point and benefit analyzing result, knowing for the stable ascent face and river bed, keeping a great deal of soil sand from descending,and suppressing soil sand disasters, in regard to the work method performance with the locale irrigation concrete foundation work goes the best with carving stone work and protecting a work lengthways. But protecting a work method lengthways of carving stone work must establish solid bed work in the appropriate length to protect in order to prevent carving stone work of protecting shore breakage from causing the chain effect leading to breaking completely. However, maneuver towards structures have to be used in collocation in order to make structures safe to avoid erosion breakage of maneuver,particularly at foundation firmness processing aspect. In this way, they have the function of heiping with each other.And by adopting sinked sand pool to defend the sand facilities work method is the urgent established engineering facility for the this area. It can reduce soil sand to descend and the discharge of mighty currents. The work method of ascent plants matches up with cover soil seeding or the work method of spraying plants and plants grass seedling and seedling wood to strengthen a buffer green strips grow plants.This is the most suitable and effective work method in usage in the area.In addition to attaining to protect the result of stability of the water solid soil and side ascent,it can also promote the regional plants to get green soon. In recent years, the weather is extreme abnormality and usually has the appearance of super and big pouring rain, which bears a great challenge towards watershed management and erosion control methods. Through the last few years of domestic and international disaster analysis, this phenomenon is already beyond artificial facilities.We can only adopt the engineer of hardware to reduce a disasters and assist with the software of evacuation.Apply carrot-and-stick ways to attain a purpose of insuring people's life and property security and national territory security.