Human Impact on the Hydrological Cycle and Consequences for Aquatic Ecosystem Services

Abstract

The hydrological cycle is essential to a stable global climate and healthy ecosystems, yet it is rapidly changing due to human actions. Human activities, including urban sprawl, industrialized agriculture, large-scale dam construction, and groundwater overdraft, have dramatically altered the natural flow regime, sediment delivery, and water quality. Although numerous studies have explored human-induced hydrological changes individually, there remains a disconnect between quantitatively modeling hydrological processes and evaluating fundamental ecosystem services (water purification, flood pulse management, habitat integrity). In this paper, it analyzes existing data on human impacts on the hydrological cycle and describe the cascade of socio-ecological impacts on the coastal wetlandriverine ecotone of the Ganges-Brahmaputra Delta. It identifies how flow regulation and increased intensity of land use degrade ecological connectivity and lead to fragmented habitats, shifted salinity regimes, eutrophication, and degraded trophic structure, resulting in a decrease in provision, regulation, and cultural services. Maladaptive feedback is evident: as natural processes decline, it relies on brittle 'grey' infrastructure, which further degrades hydrology and degradation; only by merging nature-based restoration with new technological tools like remote sensing and decentralized AI-driven predictive models will it establish restorative resilience and ensure water security.