都市綠地效益之研究：遊憩管理模型與氣候調節模型之建構

Abstract

綠地在都市中能提供多面向的生態系統服務，不僅涵蓋糧食與水源等供給服務，也同時在空氣淨化、降溫等調節服務以及休閒遊憩等文化服務上發揮關鍵作用。隨著都市持續擴張、綠地與自然棲地破碎化，導致可提供服務的空間限縮或退化，在高度人口集中的條件下對於服務的需求反而更加急迫，有鑑於此，都市自然棲地保護及綠色基礎設施規劃，已成為當前都市發展與環境治理的重要議題。為能使綠地規劃管理精準並取得最大效率，近幾年都市生態系統服務評估研究快速增長，廣泛討論生態環境變化影響效益的機制、開發多元模型，並作為管理者評估管理方案並制定決策之科學基礎。相關研究指出生態系統服務具備空間連續性與流動性，透過綠地空間連結或區域互補，小尺度的累積效益將會對較大尺度層面產生深遠影響，既有研究大多採取單一尺度的評估方法，可能因無法完整掌握生態系統服務的整體效益，導致策略失準。氣候調節服務與遊憩服務管理是都市綠地規劃管理的重要目標，本研究針對這兩項重要的生態系統服務，以多尺度的觀點分別建立環境與效益之評估模型。 遊憩服務管理方面，以陽明山國家公園鹿角坑生態保護區小觀音山區步道為研究地點，調查步道使用量與步道環境衝擊情形，依據現地調查數據與既有文獻建構環境衝擊理論模型，以路徑分析探討步道使用量與環境衝擊參數之關係。研究結果發現遊客使用量的增加直接導致步道土壤硬度上升和植栽覆蓋率下降，進而間接影響周邊環境的土壤硬度及植栽覆蓋率。此外，地方尺度的環境條件，如步道所在區域的植被種類和坡度，也顯著影響植被覆蓋率，尤其是在紅楠林區域和較大坡度地區，植被覆蓋率較低。在氣候調節服務方面，以臺北市為研究地點，應用ENVI-met模擬不同時段微氣候數值，以多元線性迴歸分析微尺度、地方尺度環境境變項影響氣溫變化的差異與貢獻，建立不同時段氣溫與環境特徵之關係式，並基於關係式以廣義相加模型分析環境與氣溫關係之影響閾值。研究發現350至400公尺範圍的環境變化對氣溫的解釋力(R²)最佳，其中周邊環境變項對氣溫的影響力普遍高於微尺度網格變項，特別是樹冠覆蓋聚集面積對微氣候調節的貢獻更為顯著。此外，不同環境變項與氣溫之間存在明顯的非線性關係及閾值效應，例如，當分析範圍內樹冠覆蓋聚集面積超過20%時，對夜間降溫效益顯著增強，而當樹冠覆蓋分散面積大於10%至15%後可呈現顯著降溫效果。 研究結果進一步釐清各種生態功能在不同層次上彼此作用的機制，為生態系統服務研究提供更完整的理論基礎，並可作為不同層級的利益關係人與決策者更具針對性與操作性之科學依據。

Urban green spaces provide a wide range of ecosystem services, including not only provisioning services like food and water, crucial regulating services such as air purification and temperature reduction, and cultural services like recreation. As urban areas grow, the fragmentation of green spaces and natural habitats leads to a contraction or degradation of the available areas for these services. At the same time, the demand for these services becomes more pressing in highly populated settings. Given this context, the conservation of urban natural habitats and the planning of green infrastructure have become major concerns in urban development and environmental management. To enhance the accuracy and efficiency of green space planning, urban ecosystem service assessments have rapidly gained traction in recent years. These studies examine how environmental changes impacted ecological benefits, developed various models, and provided a scientific basis for decision-makers to assess and implement management strategies. Research suggested that ecosystem services function continuously across space and flow between areas. Connecting green spaces or complementing functions regionally can amplify small-scale benefits into large-scale impacts. However, most existing studies relied on single-scale assessments, which may overlook the overall effects of ecosystem services, leading to suboptimal strategies. Climate regulation and recreational services are key goals in urban green space planning. This study addressed these two critical services by developing multi-scale evaluation models to assess their environmental and functional benefits. For recreational service management, this study examined the Xiaoguanyin Mountain Trail trail in the ecological protection area of Yangmingshan National Park. We surveyed trail usage and environmental impacts, constructing a theoretical model of environmental impacts based on field survey data and existing literature. Path analysis explored the relationship between trail usage and environmental impact parameters. The findings showed that increased visitor numbers directly result in increased soil hardness and decreased vegetation coverage on the trail, indirectly affecting the soil hardness and vegetation coverage in the surrounding environment. Moreover, landscape-scale environmental conditions, such as the types of vegetation and the slope in the trail area, significantly affected vegetation coverage, especially in Machilus thunbergii type forest regions and areas with steeper slopes, where vegetation coverage was lower. Regarding climate regulation services, this study focused on Taipei City, applying ENVI-met to simulate microclimate data at different times. Multiple linear regression analysis was used to assess the differences and contributions of micro-scale and local-scale environmental variables to temperature changes, establishing relationships between temperature and environmental characteristics at different times. The generalized additive model was utilized to analyze the impact thresholds of the relationships between the environment and temperature. The study found that environmental changes within a 350 to 400-meter range had the highest R² for temperature variations. Surrounding environmental variables generally influenced temperature more than micro-scale grid variables, with clustered canopy cover especially contributing significantly to microclimate regulation. Furthermore, transparent non-linear relationships and threshold effects existed between different environmental variables and temperature. For example, when clustered canopy cover exceeded 20%, the cooling benefits at night were significantly enhanced, while dispersed canopy cover above 10% to 15% showed a notable cooling effect. This study enhanced the understanding of how different ecological functions interact across multiple scales, strengthening the theoretical foundation of ecosystem service research. It also provided stakeholders and policymakers with a more practical and targeted scientific basis for decision-making.