Quantifying Regulating Ecosystem Services of Urban Trees

: A Case Study of a Green Space at Chungnam National University using i-Tree Eco

Byung Bae Park1, Wencelito Palis Hintural1*, Hee Jeong Jeon1, Seo Young Kim1

(1Department of Environment and Forest Resources, Chungnam National University, Korea)

Abstract: Urban green spaces (UGS) provide numerous ecosystem services (ES) that are essential to the well-being of the residents. Despite the numerous benefits of green spaces, measuring and valuing remain neglected or overlooked in most regional urban development and spatial planning. This study aimed to quantify the ecosystem services of a 10.25-ha UGS comprising 27 species, 287 tree individuals at Chungnam National University located in Daejeon, Republic of Korea. The study demonstrated a novel method of understanding the role of ecosystem services in regulating urban environment based on the structure and urban tree species composition using i-Tree Eco. Among the ecosystem services investigated include air pollutant removal, carbon storage and sequestration, oxygen production, reduction of energy use, avoided surface runoff, and replacement and functional values. Results revealed significant annual environmental benefits provided by the urban tree structure and composition. Specifically, the trees removed 131 kg of air pollutants (₩5.16M), sequestered 1.76 tons of carbon equivalent to 0.18 metric tons CO2 ha-1 yr-1 (₩0.40M), and produced 2.42 tons of oxygen. Additionally, the trees contributed to ₩0.54M energy savings (including carbon offset) and avoided 203m3 of surface run-off (₩0.57M). The annual total benefits of these urban trees amounted to ₩6.67M which is equivalent to ₩23,230/tree or ₩122.90/capita. Furthermore, these trees have replacement and functional values estimated at ₩429.3M. It is vital interest to note that species selection and abundance of urban trees are fundamental to maximizing the delivery of ecosystem services in urban areas. These findings highlight the important role of UGS in enhancing the ecological and economical sustainability in cities. It could also provide valuable insights for urban planners and policymakers in optimizing ecosystem benefits of green space structure and composition in cities.

Kewwords: i-Tree Eco, ecosystem services, valuation, carbon storage, carbon absorption, air pollutant removal, oxygen production, energy use, surface runoff reduction, replacement value

Acknowledgement: This work was supported by the National Research Foundation of Korea(NRF) grant funded by the Korea government(MSIT). (No. 2021R1A2C201017812)