臺北市實施綠覆率對空氣淨化累積效果之動態模擬分析

A Dynamic Simulation Analysis of Green Coverage Ratio on the Accumulative Air Pollution Alleviation Effect of Taipei City

都市綠覆率理念近年來備受國內學術界和各級政府積極推動，冀望帶動營建業在環境規劃設計實務的新潮流。然而，綠覆率這種生態設計作法在提升空氣品質，是一種動態、複雜、延滯和累積的型態，必須經過長期發展才會呈現具體效果。因此，需要一個具備整體觀、建構空氣淨化系統結構、長期動態模擬等功能的方法論，來協助人們瞭解綠覆率政策對於環境的實質生態效益，增進決策者對推動綠覆率的信心。本研究以臺北市為案例，利用系統動態學方法論的因果回饋環路，探討臺北市空氣品質下降之問題核心與找出關鍵變數，並藉由空氣淨化之系統動態模式和情境模擬分析，說明執行綠覆率政策對於未來減緩臺北市空氣污染氣體量的具體效果和宏觀價值。研究發現：國內營建業若能長期實施綠覆率，將能具體增加都市綠地面積並增進綠地吸收污染氣體能力，具備淨化都市空氣之效果。因此，綠覆率是非常值得長期推廣的都市永續發展作法。

The idea of green coverage ratio recently is interested by governments and research fields of environmental planning and design for cooperation with the practical fields of building trades. However, air purification effect of green coverage ratio works as a form of dynamic, complex, delayed, and accumulated action, which needs a longer-term for evaluation. Therefore, the policy analysis of green coverage ratio needs a special methodology with a holistic view to help decision maker to have confidence by building its accumulated construction of air purification system and simulating its long-term dynamic development trend. In this article, Taipei’s problem of declined air quality is demonstrated, which shows the long-term air purification effect and the holistic value of green coverage ratio by applying causal feedback loops, dynamic simulation models, and scenarios analysis under System dynamics (SD) approach. Results show that policy of increasing green coverage ratio would bring significant contributions to increase urban green land area and its modification ability to air purification effect. Therefore, the policy of increasing green coverage ratio is worth to carry out for urban sustainable development.