Climate Change Responses in Freshwater Ecosystems

Abstract

Climate change is increasing disturbance in freshwater ecosystems and modifying hydrological processes, ecological stability, and ecosystem functioning. Intensified droughts, changed rainfall patterns, heatwaves, and flooding events are altering river, wetland, lake, and estuarine systems over several spatial scales. Although there is abundant literature documenting ecological damage from climatic variability, little attention has been given to the mechanisms by which ecological stability of freshwater ecosystems is maintained under ongoing climatic disruption. The purpose of this review is to bring together current understanding of the relationships between climate-driven hydrological change and freshwater ecosystems. In particular, emphasis is placed on ecological thresholds, biodiversity buffering capacity, adaptive behavior, and governance mechanisms which promote ecosystem recovery from impacts. In the second half of the review, an integrated framework that links climatic influences with ecological impacts and adaptive pathways is proposed. Results suggest that connectivity, diversity of ecological functions, ecological memory and institutional fluidity can strongly promote ecosystem resilience. The long-term sustainability of freshwater ecosystems will ultimately depend on the capacity of their management regimes to respond to environmental variability, non-linear responses and increasing rates of change.