Ecosystem Services of the Historic Landscape Forest of Jinju Fortress, South Korea: A Species-Level Assessment Using i-Tree Eco

Historic landscape forests within cultural heritage sites represent a distinct category of urban green space that provides critical ecosystem services under strict conservation constraints. This study applied i-Tree Eco v6.0 to quantify the ecosystem services of the historic landscape forest of Jinju Fortress (Jinjuseong; Historic Site No. 118), South Korea, with focus on species-level contributions. A total of 822 trees representing 30 species were inventoried across 1.272 ha of tree cover. Zelkova serrata was the dominant species (importance value = 57.8) and contributed disproportionately to all ecosystem service categories, accounting for 40.7% of air pollutant removal, 61.3% of carbon storage, 58.2% of carbon sequestration and oxygen production, and 55.4% of avoided runoff. The forest removed 123.1 kg yr−1 of air pollutant Korean Won (KRW 8.834 million yr−1), stored 200.7 t (KRW 138 million), sequestered 8.834 t/yr (KRW 6.09 million/yr), produced 23.56 t/yr−1 of oxygen, avoided 10,413.7 L yr−1 of runoff and had a structural replacement value of KRW 1.63 billion. Beyond providing a species-level baseline for evidence-based management, this study introduces the concept of Heritage Ecosystem Service Efficiency (HESE) and the Species Ecosystem Service Dominance Index (SESDI), offering transferable frameworks for evaluating and managing ecosystem service performance in conservation-constrained heritage forests.