Climate Change Impacts on Hydrological Cycle and Aquatic Ecosystem Health

Abstract

Anthropogenic climate change has accelerated the intensification of the global hydrological cycle, triggering a global ecological emergency for aquatic ecosystems. Irregular precipitation, severe droughts, and extreme flooding have disrupted established thermal, chemical, and structural aquatic regimes, potentially threatening frail aquatic ecosystems with critical ecological tipping points. Such physical disruptions are resulting in significant biological repercussions such as massive losses in biodiversity, disruption of migration corridors through fragmentation of flood pulses, and increases in hypolimnetic hypoxia due to pronounced thermal stratification. Although many of these responses have been well documented individually in various published literature, a critical knowledge gap exists in the integrated, predictive frameworks that directly associate multi-stressor effects with specific ecological thresholds. To address this deficiency, this research uses a multi-scalar analytical framework combining high-resolution EO with high-accuracy Spatiotemporal Geostatistical Modeling and machine learning techniques. This research presents a novel index, the EHVI, used to measure and map high-risk aquatic habitats susceptible to degradation by climate. The results indicate a decrease in ecosystem resilience due to synergistic effects, specifically from interactions between hydrological variability and nutrient enrichment. Evidence-based approaches to ecosystem management using ecosystem-based adaptation, such as wetland buffer zones, floodplain fragmentation, and predictive modeling for adaptive water allocation, should be considered to address such system failures. Through the effective implementation of such adaptive conservation and management approaches, the study highlights a scalable tool for use by decision-makers to build long-term aquatic ecosystem resilience and continue providing key ecosystem services at regional and global scales.