臺灣常見闊葉樹種葉面滯留懸浮微粒定量分析

Quantifying Particulate Matter Deposition on Leaf Surfaces of Common Broadleaved Tree Species in Taiwan

林彥廷(Yen-Ting Lin)

指導教授 ： 柯淳涵

國立臺灣大學/生物資源暨農學院/森林環境暨資源學研究所/碩士(2014年)

https://doi.org/10.6342/NTU.2014.01275

摘要

都市化常會降低當地與區域性的環境品質，造成世界上主要城市嚴重的空氣汙染。懸浮微粒造成人類健康發生問題主要與其粒徑的大小有關，眾多的醫學研究指出曝露在高濃度的懸浮微粒中將導致夭折及對心血管、呼吸系統產生有害的影響。近來，關注更已轉移到細懸浮微粒上面。隨著過去幾十年來快速的城市化和工業化，台灣正面臨重要的空氣品質問題，特別是南部的一些城市。因此，有效尋求各種方案，包括透過種樹與設置其它綠化設施等方式建置空氣品質淨化區（CAZs）以降低城市地區懸浮微粒的濃度是極為重要的。樹木可藉由乾式沉降有效率的從大氣中捕獲懸浮微粒，移除大量空氣汙染物，改善城市周遭環境品質與人體健康。十五種生長在空氣品質淨化區內的闊葉樹種被選擇作為葉面滯留懸浮微粒之定量分析。十五種樹種葉面皆可從大氣中捕捉粒徑10 μm以下之懸浮微粒。在對人體傷害較大之PM10和PM2.5懸浮微粒滯塵方面，以臺灣欒樹、鳳凰木、黃金風鈴木與大葉欖仁為主要推薦樹種。當交通排放為主要汙染源時，榕樹、樟樹、臺灣欒樹、大葉欖仁、陰香、黃槿、印度紫檀、鳳凰木等樹種可當作較佳之生物濾器捕捉懸浮微粒；而當土壤揚塵和飛灰排放為主要汙染源時，則以大葉桃花心木、黑板樹、苦楝、大葉山欖、阿勃勒、火焰木等樹種較佳。在十五種樹種中，以黃金風鈴木去除大氣中硫氧化物的能力最高，其次依序為樟樹、臺灣欒樹、黃槿、陰香和大葉欖仁。再者，生長於台北市和高雄市的榕樹被選擇用來測定葉面滯留懸浮微粒的空間變化。高雄市榕樹葉面滯留懸浮微粒量約為台北市的兩倍，可能與其乾燥的天氣及高度工業活動所造成總粉塵濃度較高有關。台北市中山區榕樹葉面滯留懸浮微粒量較高可能受到附近兩條快速道路所造成較嚴重的交通排放有關；而高雄市小港區與鳳山區榕樹葉面滯留懸浮微粒量較高則可能分別受到高雄國際機場與國道一號的汙染排放有關。台北市可能的汙染排放源包括土壤揚塵和飛灰、汽車排放、工業和燃料油燃燒、二次氣溶膠、生物質燃燒與垃圾焚燒；而高雄市則包括土壤揚塵和飛灰、汽車排放、工業和燃料油燃燒、二次氣溶膠、海洋氣溶膠、生物質燃燒與垃圾焚燒。生長於台北和高雄的榕樹具有相當去除大氣中硫氧化物和氮氧化物的能力。至於台北市榕樹葉面滯留懸浮微粒含較高之氯離子濃度可能受到較多垃圾焚燒的排放所引起。

關鍵字

懸浮微粒 ； 空氣品質淨化區 ； 乾式沉降 ； 滯塵 ； 排放 ； 闊葉樹種 ； 榕樹

並列摘要

Urbanization often degrades local and regional environmental quality and causes air pollution in most major cities across the world. A number of medical studies had indicated that exposure to high concentrations of fine particulates can cause premature death and harmful effects on the cardiovascular and respiratory system. Along with a rapid urbanization and industrialization during the past few decades, Taiwan is facing important air quality problems, especially in some southern cities of Taiwan. It is vital to explore all alternatives to lower concentration of particulate matters (PM) in urban areas, including setting up Clean Air Zones (CAZs) through planting and other greening facilities installed. Trees can efficiently capture particles from the atmosphere by dry deposition. Fifteen broadleaved tree species growing within the sampled CAZs in Northern Taiwan were selected for quantification of PM deposition on foliage. All fifteen trees species are helpful on capturing coarse and fine particulates from the atmosphere. For PM2.5-10 and PM0.2-2.5, Koelreuteria henryi, Delonix regia, Tabebuia chrysantha, and Terminalia catappa are best candidates for afforestation. Ficus. microcarpa, Cinnamomum camphora, K. henryi, T. catappa, Cinnamomum burmanii, Hibiscus tiliaceus, Pterocarpus indicus, and D. regia are good biological filters to capture airborne particles when vehicular emission is considered as the main source, while Swietenia macropnylla, Alstonia scholaris, Melia azedarach, Palaquium formosanum, Cassia fistula, and Spathodea campanulata are good biological filters under soil dust and fly ash emission. T. chrysantha, C. camphora, K. henryi, H. tiliaceus, C. burmanii, and T. catappa possessed the higher capability of removing SOx emissions from the atmosphere. Moreover, F. microcarpa is selected for determining the spatial variations of PM deposition in both Taipei and Kaohsiung Cities. The PM deposition on F. microcarpa growing in Kaohsiung City is almost two times higher than that in Taipei City which may be related to its dry weather and total dust concentration due to high industrial activity proceeded, whereas the higher PM deposition on F. microcarpa growing in Jhongshan District, Taipei, is possible due to heavier traffic emission from two Overpasses nearby, and the higher PM deposition on F. microcarpa growing in Xiaogang and Fengshan District, Kaohsiung, were contributed by Kaohsiung International Airport emissions and heavier traffic emission from Taiwan National Highways no. 1, respectively. The possible emission sources in Taipei City are ‘soil dust and fly ash’, ‘vehicular’, ‘mixed industrial/fuel-oil combustion’, ‘secondary aerosols’, ‘biomass burning’ and ‘garbage burning’, and the possible emission sources in Kaohsiung City are ‘soil dust and fly ash’, ‘vehicular’, ‘mixed industrial/fuel-oil combustion’, ‘secondary aerosols’, ‘marine aerosols’, ‘biomass burning’ and ‘garbage burning’. F. microcarpa growing in both Taipei and Kaohsiung Cities possess equivalent capability of removing SOx and NOx emissions from the atmosphere, whereas the higher concentration of Cl‾ in Taipei City is possibly attributed to more emissions from garbage burning.

並列關鍵字

particulate matter ； Clean Air Zones ； dry deposition ； dust retention ； emission ； broadleaved tree species ； Ficus microcarpa

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