生態系統服務評核臺灣水域生態研究

Abstract

生態檢核機制是國內近年推動的環境友善政策之一，其可追溯自2006年石門水庫集水區風災整治計畫，由於過往的工程型態多偏重於混凝土的硬性工法，對於生態層面的考量較為薄弱，不利於整體環境復原發展，生態檢核概念遂被提出。另外在國際社會上，生態系統服務的概念已逐漸成為生態檢核的重點之一，然國內針對生態系統服務的探討尚處於啟蒙階段，亦未考量水質等直接影響到生物存活的因子，水質狀況與魚類族群豐富度及數量有正相關之關係外，低溶氧、水體濁度、懸浮固體濃度，為導致魚類死亡事件之可能因素。水質對於生物環境以及人類生活具有相當重要性，故本研究的核心在於導入生態系統服務的探討與水體水質的分析，期能提供更完善的機制與工程設計理念。 本研究首先針對生態檢核、生態系統服務與水質等議題進行文獻回顧。第一，蒐集國內近年常用的生態檢核機制，介紹生態檢核的流程以及其核心價值，列表進行比較與說明，同時透過文獻的蒐集，了解生態檢核機制的變革與修正歷史；其次，回顧生態系統服務的相關文獻資料。生態系統服務一詞最早可追溯自1970年代，由Westman於1977年提出，後有眾多學者針對不同領域的服務項目進行分析與探討，將其化為供給、調節、支持及文化等四大類別，本研究亦分別針對國內陸地水體，進行生態系統服務功能的探討。 其次，本研究分析比較目前國內生態檢核機制的差異與其優缺點，大多數皆分為核定階段、規劃設計階段、施工階段及維護管理階段，各階段的生態檢核目標與意義均不相同。從中可知，目前各機制調查的生態重點均為環境棲地等物理特性，對於水質及影響人民生活福祉的生態系統服務功能未多做涉略。隨著生態保育意識的抬頭與多功能性的規劃發展，水質及生態系統服務的探討更顯重要。故本研究針對各機制進行分析，探討納入生態系統服務評估與水質採樣及分析的時機點，並擬定相關表格供從業人員或生態人員使用，期以上位計畫的時間進程，將相關概念即早納入設計理念考量中，以創造符合工程效益、生態保育及服務功能等全面性的規劃，減少缺乏完善考量而衍生的疏失及進度延宕。 最後從水利署「河川、區域排水及海岸工程生態檢核作業」、水土保持局「生態檢核標準作業書」及林務局「國有林治理工程生態友善機制手冊」等三大生態檢核作業流程，各選出一例案例進行操作，以比較帶入生態系統服務與水質評核前後的差異。其結果顯示，若能及早進行生態系統服務評估與水質採樣分析，則可透過迴避措施，避免對生態敏感區位或重要水源區域進行擾動，而喪失基因資源或水供應等服務；透過縮小措施，限制開挖擾動範圍，減少對於環境的破壞，保有生物棲地而鞏固棲地或物種多樣性等服務；透過減輕措施，施作臨時性沉砂空間，降低水中泥砂含量及濁度對於水中生物的影響，也能保持水質的穩定；透過補償行為，維持生態系統的平衡及恢復穩定的水質條件，進而將周邊價值發揮出最大效益。

The ecological check mechanism is one of the environmentally friendly policies promoted in Taiwan. It was first proposed in 2006 after the storm disaster remediation of the Shimen Reservoir watershed. Since the past engineering types tended to focus on the hard construction methods such as concrete, the consideration of ecology is relatively weak, which is not conductive to the development of environmental recovery. Otherwise, the concept of ecosystem services has gradually become one of the key points of ecological check of other countries. However, domestic discussions on ecosystem services are still in the enlightenment stage. Also, the factors that directly affect the survival of organisms in the water have not been considered. So, the core of this research is to import ecosystem services and water quality analysis into ecological check. And it is expected to provide a more complete mechanism and engineering design concept. This research first reviewed the literature on issues such as ecological check, ecosystem services and water quality. First, we collect the ecological check mechanism commonly used in Taiwan, introduce the ecological process and its value, compare and explain of each mechanism, and at the same time, understand the history of ecological check mechanism reform and revision; second, review relevant literature on ecosystem services. The term “ecosystem service” can be traced back to the 1970s, and was proposed by Westman in 1977. Later, many scholars analyzed and discussed service projects in different fields, and turned it into four categories: Supply service, Regulation service, Support service and Culture service. Next, this research analyzed and compares the differences, advantages and disadvantages of domestic ecological check mechanism, most of which are divided into the verification stage, the planning and design stage, the construction stage, and the maintenance and management stage. The ecological check objectives and meanings of each stage are different. It can be seen from the above that the current ecological focus investigated by each mechanism is physical characteristics such as environmental habitats, and there is not much involved in the water quality and ecosystem service functions that affect people’s well-being. With the rise of ecological conservation awareness and the development of multifunctional planning, the discussion of water quality and ecosystem services has become more important. Therefore, this research analyzes each mechanism, discusses the timing of including ecosystem service assessment and water quality sampling and analysis, and formulates relevant forms for practitioners or ecological personnel. The time course of the high-level plan in the current period will incorporate relevant concepts into the design concept considerations in order to create comprehensive plans that are in line with engineering benefits, ecological conservation and service functions, etc., to reduce the negligence and schedule delays caused by the lack of prefect considerations. Finally, from the three major ecological assessment operations of the Water Resources Agency, MOEA 'river, regional drainage and coastal engineering ecological assessment operation', the Soil and Water Conservation Bureau 'ecological assessment standard operation book' and the Forestry Bureau 'state-owned forest governance project ecological friendly mechanism manual'. In the process, one case was selected for operation to compare the differences before and after bringing into the ecosystem service and water quality assessment. The results show that if ecosystem service assessment and water quality analysis can be carried out as early as possible, it is possible to avoid disturbance of ecologically sensitive areas or important water source areas through the avoidance measures, and the loss of services such as genetic resources or water supply; through narrowing measures, restrict the excavate and disturbance range, to reduce the damage to the environment and maintain biological habitats and consolidate habitats or species diversity, and other services; through mitigation measures, apply temporary sedimentation space to reduce the impact of mud content and turbidity on aquatic organisms, can also maintain the stability of water quality; through compensation, maintain the balance of the ecosystem and restore stable water quality conditions, and then maximize the value of the surrounding value.