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USGS · 70283620

The riverine legacy of reservoirs

Abstract

Reservoirs exposed to similar environmental drivers frequently exhibit markedly different ecological responses. Existing reservoir concepts describe many aspects of impounded rivers, but none directly explains why environmental drivers produce contrasting ecological responses among reservoirs. I propose riverine legacy , defined as the enduring ecological characteristics that reservoirs inherit from the rivers they impound. Riverine legacy arises because impoundment transforms river systems without completely erasing their spatial, environmental, ecological, and trophic organization. Riverine legacy consists of five interconnected dimensions through which inherited characteristics interact with contemporary environmental drivers to generate ecological responses at population, community, and ecosystem levels. I provide three examples to illustrate how riverine legacy may explain contrasting responses to biological invasions, longitudinal variation in community organization, and differences in ecological transformation among impounded rivers. The concept yields six testable predictions concerning ecological organization, ecosystem responsiveness, fisheries, recovery trajectories, and conservation opportunities across reservoir networks. Riverine legacy is not proposed as a metric but as a concept that generates testable hypotheses about how inherited riverine characteristics influence contemporary ecological responses. Recognizing that reservoirs retain enduring ecological characteristics inherited from their riverine origins provides a foundation for improving ecological interpretation, conservation planning, monitoring, management, and restoration across impounded river systems.

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BibTeXRIS

Leandro E. Miranda. 2026-10-16. The riverine legacy of reservoirs. https://doi.org/10.3389/ffwsc.2026.1967253

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