Ecological dynamics and carbon sequestration in the 150 kV Tentena–Kolonedale transmission corridor

The construction of the 150 kV Tentena-Kolonedale high voltage overhead transmission line (SUTT) requires clearing a right of way (RoW) corridor to ensure the safety and reliability of the power transmission system, an activity that can alter land cover and reduce biomass, carbon stock, and CO 2 sequestration capacity.This study evaluated land cover change in the RoW corridor of the 150 kV Tentena-Kolonedale line and its effect on biomass, carbon stock, CO 2 sequestration, and the economic value of carbon, focusing on the segment between Tower TIP 92 and TIP 99 in Poso and North Morowali Regencies, Central Sulawesi.Land cover change was analyzed using multitemporal Sentinel-2 NDVI imagery for 2019-2024, while biomass, carbon stock, CO 2 sequestration, and carbon economic value were estimated using IPCC (2019) conversion factors.Results show the corridor remained dominated by high-density vegetation throughout the observation period, ranging from 85.52 to 91.04 ha.Highdensity vegetation decreased only marginally, from 90.89 ha in 2019 to 90.88 ha in 2024 (-0.01 ha, 0.01%), so more than 99% of the corridor retained dense vegetation cover.Biomass ranged from 12,828 to 13,656 tons, carbon stock from 6,029.16 to 6,418.32 tons C, and potential CO 2 sequestration from 22,126.02 to 23,555.23 tons CO 2 e, with the estimated economic value of carbon ranging from IDR 3.32 to 3.53 billion, peaking at IDR 3,533,284,500 in 2023.Comparing 2019 and 2024 conditions reveals a loss of 1.50 tons of biomass, 0.76 tons C of carbon stock, 2.79 tons CO 2 e of sequestration potential, and about IDR 418,500 (±0.01%) in carbon economic value.These findings indicate that construction and management of the corridor caused only very limited land cover change and carbon loss.The observed vegetation changes were relatively small, indicating limited ecological disturbance during the observation period; because formal statistical significance testing was not performed, these findings are interpreted descriptively rather than inferentially, though dominant high-density vegetation continued to sustain the corridor's function as both a carbon sink and stock.The integration of Sentinel-2 NDVI analysis with biomass and carbon estimation proved effective for evaluating the ecological impact of transmission-line infrastructure, supporting sustainable vegetation management and carbon mitigation strategies.