Integrating structural, functional, and compositional dimensions to assess ecosystem resilience under hydroclimatic extremes: a case study in the Panlaung River Basin, Myanmar

Ecosystems face challenges from hydroclimatic extremes; however, current approaches to assess ecological resilience often rely on a single indicator that fails to capture the multidimensional nature of ecosystem responses. This study introduces a comprehensive framework for quantifying ecosystem resilience, integrating structural, functional, and compositional metrics into a unified Ecosystem Resilience Index (ERI). We applied this framework to the Panlaung River Basin in Myanmar, analyzing satellite-derived indicators (2003–2024) to evaluate ecosystem responses to long-term hydroclimatic variability, severe drought conditions and extreme flooding induced by the 2024 Typhoon Yagi. Our analysis revealed distinct, often decoupled, trajectories across resilience dimensions. Over the study period, structural resilience remained consistently high across all ecosystems (mean value > 0.95) whereas functional resilience showed a persistent basin-wide decline since 2014. Compositional resilience exhibited the highest variability, with riparian zones experiencing sharp drops during both dry (∼0.668) and wet extremes (∼0.855). Furthermore, ecosystem responses varied significantly by type; forested ecosystems demonstrated enhanced resilience under drier conditions, while croplands and grasslands performed better during wetter periods. During acute extreme events, the integrated ERI captured vulnerabilities often masked by individual metrics. Post-drought recovery analysis indicates a significant decoupling of recovery dimensions: while functional and compositional indicators suggest near total recovery within 5 years, structural resilience exhibited a persistent lag, particularly in Temperate-Boreal system. Under extreme inundation, probabilistic flood-depth sensitivity analysis suggests an empirical depth threshold of 2–4 m in this basin, beyond which resilience loss accelerates. By integrating divergent responses across resilience dimensions, the ERI provides a more robust and conservative assessment than individual metrics by moderating trade-offs between rapid physiological rebounds and lagged structural restoration.