Size‐dependent effects of dams on river ecosystems and implications for dam removal outcomes DOI Creative Commons
Rebecca L. Brown, Donald F. Charles,

Richard J. Horwitz

et al.

Ecological Applications, Journal Year: 2024, Volume and Issue: 34(6)

Published: Aug. 13, 2024

Understanding the relationship between a dam's size and its ecological effects is important for prioritization of river restoration efforts based on dam removal. Although much known about large storage dams, this information may not be applicable to small which represent vast majority dams being considered To better understand how vary with size, we conducted multidisciplinary study downstream effect range characteristics including geomorphology, water chemistry, periphyton, riparian vegetation, benthic macroinvertebrates, fish. We related variables downstream-upstream fractional difference in measured 16 mid-Atlantic region ranging from 0.9 57 m high, hydraulic residence times (HRTs) 30 min 1.5 years. For physical attributes, larger had effects. example, surface width below was greater dams. By contrast, there no sediment grain though fraction fine-grained bed material lower independently size. Larger tended reduce quality more, decreased dissolved oxygen increased temperature. inorganic nutrients (N, P, Si), but particulate P) reaches. Aquatic organisms have dissimilarity species composition (for fish periphyton), taxonomic diversity macroinvertebrates), pollution tolerance periphyton macroinvertebrates). Plants responded differently fewer invasive more Overall, these results demonstrate that impact ecosystem components measured, hence their removal has greatest potential restoring ecosystems.

Language: Английский

Broad‐Scale Meta‐Analysis of Drivers Mediating Adverse Impacts of Flow Regulation on Riparian Vegetation DOI Open Access
Xiaolei Su, María Dolores Bejarano, Roland Jansson

et al.

Global Change Biology, Journal Year: 2025, Volume and Issue: 31(2)

Published: Feb. 1, 2025

ABSTRACT Over two‐thirds of global rivers are subjected to flow regulation. Although it is widely recognized that regulation can adversely affect riparian vegetation—a critical component river ecosystems—the specific roles various drivers remain poorly understood. To address this gap, we conducted a broad‐scale meta‐analysis, aiming elucidate how different factors mediate the adverse impacts on vegetation. This meta‐analysis encompassed 59 papers, spanning 278 dams constructed 146 rivers. We extracted data four key indices vegetation: species richness and abundance all species, those exclusively for non‐native species. Indices were compared between regulated free‐flowing or pre‐damming quantify impact Our revealed moderate but significant reduction in under regulation, coupled with strong increase Riparian vegetation arid continental climate regions experienced stronger negative than tropical temperate climates. Furthermore, effects more pronounced downstream upstream. Considering region, study identity, relative position dam as random variables, became evident years since emerged most important factor influencing richness. time, gradually recovered from initially low levels. However, recovery was slowed by increasing intensity (percentage annual runoff stored). Additionally, larger support management, recommend prioritizing protection climates, emphasis areas dams, limiting intensity, particularly rivers, monitoring prevent disproportionate spread.

Language: Английский

Citations

0
Hydrological connectivity: a review and emerging strategies for integrating measurement, modeling, and management DOI Creative Commons
Dipankar Dwivedi, Ronald E. Poeppl, Ellen Wohl

et al.

Frontiers in Water, Journal Year: 2025, Volume and Issue: 7

Published: March 31, 2025

This review synthesizes methods for measuring, modeling, and managing hydrologic connectivity, offering pathways to improve practices address environmental challenges (e.g., climate change) sustainability. As a key driver of water movement nutrient cycling, connectivity influences flood mitigation, quality regulation, biodiversity conservation. However, traditional field-based dye tracing), indirect measurements runoff analysis), remote sensing techniques InSAR) often struggle capture the complexity catchment-scale interactions. Similarly, modeling approaches—including process-based percolation theory-based models, graph theory, entropy-based metrics—face limitations in fully representing these interconnected processes. Both measurement are constrained by inadequate spatial temporal coverage, high data demands, computational complexity, difficulties subsurface connectivity. Subsequently, we critique current management that prioritize isolated variables streamflow, sediment transport) over system-wide strategies emphasize need adaptive, connectivity-based approaches resource planning restoration. Moving forward, highlight importance interdisciplinary collaboration, technological innovations AI-driven real-time monitoring), integrated frameworks measurement, adaptive restore fragmented networks. approach sets stage transformative management, fostering proactive policy development stakeholder engagement.

Language: Английский

Citations

0
Size‐dependent effects of dams on river ecosystems and implications for dam removal outcomes DOI Creative Commons
Rebecca L. Brown, Donald F. Charles,

Richard J. Horwitz

et al.

Ecological Applications, Journal Year: 2024, Volume and Issue: 34(6)

Published: Aug. 13, 2024

Understanding the relationship between a dam's size and its ecological effects is important for prioritization of river restoration efforts based on dam removal. Although much known about large storage dams, this information may not be applicable to small which represent vast majority dams being considered To better understand how vary with size, we conducted multidisciplinary study downstream effect range characteristics including geomorphology, water chemistry, periphyton, riparian vegetation, benthic macroinvertebrates, fish. We related variables downstream-upstream fractional difference in measured 16 mid-Atlantic region ranging from 0.9 57 m high, hydraulic residence times (HRTs) 30 min 1.5 years. For physical attributes, larger had effects. example, surface width below was greater dams. By contrast, there no sediment grain though fraction fine-grained bed material lower independently size. Larger tended reduce quality more, decreased dissolved oxygen increased temperature. inorganic nutrients (N, P, Si), but particulate P) reaches. Aquatic organisms have dissimilarity species composition (for fish periphyton), taxonomic diversity macroinvertebrates), pollution tolerance periphyton macroinvertebrates). Plants responded differently fewer invasive more Overall, these results demonstrate that impact ecosystem components measured, hence their removal has greatest potential restoring ecosystems.

Language: Английский

Citations

3