Natural Filters: The Impact of Urban Plants on Air Quality

Öz

Plants are among the first solutions considered in the fight against air pollution. As natural and effective agents, they play a vital role. However, success depends on selecting the right species and placing them in suitable climates and locations. When properly chosen, plants can significantly improve air quality and support sustainable urban environments. This study focuses on the concept of "natural filtration," particularly "the role of trees," using the city of Trabzon as the study area. Two sites were selected: one with dense urban vegetation and the other with sparse vegetation. Emission measurements were conducted and analyzed statistically. Results revealed that broad and oval-leaved plants had greater potential to enhance micro air quality. Among all species, Rhododendron cynthia had the most consistent positive effect across all seasons. In spring, the park’s average air quality was 95.48 µg/m³, with R. cynthia recording 357.44 µg/m³. In summer, the average was 106.87 µg/m³, while this species measured 310.37 µg/m³. Autumn showed 124.74 µg/m³ overall, and Rhodendron cynthia had 201.43 µg/m³. In winter, it had the lowest CO emission at 1.03 µg/m³, while the average was 107.96 µg/m³. These findings emphasize the species’ strong potential to improve air quality. Furthermore, 80% of the species with the highest air quality contribution were trees, suggesting they should be prioritized in landscape planning. ANOVA results showed that broad and oval-leaved trees had a significant positive impact, while the difference between deciduous and evergreen species was not significant. In conclusion, urban plants' effectiveness in improving air quality depends on species, leaf shape, and growth form. These findings serve as a guide for environmentally sustainable and informed landscape planning.

Anahtar Kelimeler

• Air quality index
• Air pollution
• Urban plants

Doğal Filtreler: Şehir Bitkilerinin Hava Kalitesine Etkisi

Öz

Bitkiler, hava kirliliğiyle mücadelede ilk akla gelen çözümler arasındadır. Doğal ve etkili unsurlar olarak önemli bir rol oynarlar. Ancak bu süreçte başarı, doğru bitki türlerinin seçilmesi ve uygun iklim koşullarına ve alanlara yerleştirilmesine bağlıdır. Uygun seçimlerle, bitkiler hava kalitesini artırabilir ve sürdürülebilir kentsel çevreler oluşturabilir. Bu çalışma, "doğal filtrasyon" kavramı ve özellikle "ağaçların rolü" üzerine odaklanmakta olup, çalışma alanı olarak Trabzon kenti seçilmiştir. Biri yoğun bitki örtüsüne, diğeri ise az bitki örtüsüne sahip iki alan belirlenmiştir. Bu alanlarda emisyon ölçümleri yapılmış ve istatistiksel olarak analiz edilmiştir. Sonuçlar, geniş ve oval yapraklı bitkilerin mikro hava kalitesini artırmada daha etkili olduğunu göstermiştir. Tüm türler arasında Rhododendron cynthia, dört mevsim boyunca hava kalitesini en fazla iyileştiren tür olmuştur. İlkbaharda parkın ortalama hava kalitesi 95.48 µg/m³ iken, Rhododendron cynthia 357.44 µg/m³ değerine ulaşmıştır. Yazın ortalama 106.87 µg/m³, bu türde ise 310.37 µg/m³ ölçülmüştür. Sonbaharda genel ortalama 124.74 µg/m³ olup, Rhododendron cynthia 201.43 µg/m³ değer göstermiştir. Kışın ise ortalama 107.96 µg/m³ iken, bu tür en düşük CO emisyonunu 1.03 µg/m³ ile göstermiştir. Bulgular, bu türün hava kalitesini artırmadaki güçlü potansiyelini ortaya koymaktadır. Ayrıca, hava kalitesine en fazla katkı sağlayan türlerin %80’inin ağaç formunda olduğu tespit edilmiş ve bu türlerin kentsel peyzaj planlamasında önceliklendirilmesi gerektiği sonucuna varılmıştır. ANOVA testi sonuçlarına göre, geniş ve oval yapraklı ağaçlar hava kalitesine daha fazla katkı sağlarken, yaprağını döken ve herdem yeşil türler arasında anlamlı bir fark bulunmamıştır. Sonuç olarak, kentsel bitkilerin hava kalitesini iyileştirme potansiyeli; tür, yaprak morfolojisi ve büyüme formuna bağlıdır. Bu bulgular, çevresel sürdürülebilirliği destekleyen bilinçli peyzaj planlaması için önemli bir rehber niteliğindedir.

Anahtar Kelimeler

• Hava kalitesi indeksi
• Hava kirliliği
• Kent bitkileri

Kaynakça

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