Evaluation of the applicability of elasticity curve-based future projections for Mountain Wetlands

Mountain wetlands respond sensitively to climate change; however, projections of their changes are limited by the lack of long-term hydrological and vegetation observations. This study evaluated the extent to which elasticity curve-based projections (ECBP) could reproduce the projections of the process-based wetland eco-hydrologic model (WBP) for Janggun Wetland and Hwaeom Marsh in South Korea. Using climate data and simulation data from 1984 to 2025, elasticities were estimated for the 15th, 50th, and 85th percentiles of wetland water level and leaf area index (LAI), and the projection results for the near future (2041–2070) and far future (2071–2100) were compared by applying 40 climate forcings. Water level showed high agreement at the 50th percentile in both wetlands; however, ECBP estimated a magnitude of water level increase at Janggun Wetland, whereas the projected water-level changes from both methods were concentrated near 0% at Hwaeom Marsh. LAI showed the highest agreement at the 85th percentile in both wetlands, but ECBP underestimated both the variability across climate conditions and the likelihood of decreases in both wetlands. In addition, discrepancies between the two methods, including the magnitude of change and reversals in the direction of change, increased as climate conditions moved beyond the historical range of variability or as changes in precipitation, PET, or maximum temperature became larger. Based on these results, this study identified the range of applicability and the limitations of ECBP for exploring the direction of future change and climate sensitivity under water level and LAI conditions in mountain wetlands.