Salinity regulates nutrient cycling via top-down and bottom-up forces in artificial cut-off tidal channels: Insights from multitrophic microbiota.

Artificial cut-off of natural tidal meanders for flood control has substantially altered microbial communities and their role in nutrient cycling, yet the lack of comprehensive investigations into these specific anthropogenic impacts introduces greater uncertainty regarding the resultant water quality of nutrient-enriched estuaries. Here, we investigated how planktonic multitrophic microbiota and their mediated nutrient cycling respond to artificial meander cut-off using the environmental DNA (eDNA) approach. Results showed that despite the decline in α diversity of multitrophic microbiota, the nutrient cycling potential of the water column was enhanced 2.91-fold in the straight tidal channel. The artificial cut-off restructured the microbial food web, with trophic transfer efficiency from basal species to protozoa increasing. Salinity was identified to be the key environmental driver, mitigating the negative impact of decreased biodiversity on estuarine nutrient cycling potential by intensifying protozoan predation on heterotrophic bacteria (top-down forces). Additionally, salinity further enhanced environmental selection (bottom-up forces), reducing heterotrophic bacterial diversity while promoting the proliferation of functional microbial taxa, such as Comamonadaceae, Chitinophagaceae, and Rhodocyclaceae. This study offers novel insights into nutrient cycling in artificial straight tidal channels and provides critical foundations for optimizing restoration and management strategies in anthropogenically modified tidal river.

• Publication year

  2025

• Venue

  Water Research

• Publication date

  2025-06-01

• Fields of study

  Biology, Medicine, Environmental Science

• Identifiers
  DOI 10.1016/j.watres.2025.124037PMID 40561631
• External record

  Open on Semantic Scholar

• Source metadata

  Semantic Scholar, PubMed

• No claims are published for this paper.

• No concepts are published for this paper.

• Ecological interactions amplify cumulative effects in marine ecosystems

  2025cited by this paper
• Hysteretic and asynchronous regime shifts of bacterial and micro-eukaryotic communities driven by nutrient loading.

  2024cited by this paper
• Hydrodynamics of Meander Chute Cutoffs in Microtidal Mudflats

  2024cited by this paper
• Global biogeography of microbes driving ocean ecological status under climate change

  2024cited by this paper
• Interactions Between River Floods and Human Activities on Sediment Transport in a Macrotidal Estuary

  2024cited by this paper
• Globally elevated greenhouse gas emissions from polluted urban rivers

  2024cited by this paper
• An integrated spatio-temporal view of riverine biodiversity using environmental DNA metabarcoding

  2024cited by this paper
• Sequential decline in cyanobacterial, total prokaryotic, and eukaryotic responses to backward flow in a river connected to Lake Taihu.

  2024cited by this paper
• Below‐ground traits, rare species and environmental stress regulate the biodiversity–ecosystem function relationship

  2024cited by this paper
• Plant diversity enhances ecosystem multifunctionality via multitrophic diversity

  2024cited by this paper
• How urban form impacts flooding

  2024cited by this paper
• How nutrient loading leads to alternative stable states in microbially mediated N-cycle pathways: A new insight into bioavailable nitrogen removal in urban rivers.

  2023cited by this paper
• Integrating climate change induced flood risk into future population projections

  2023cited by this paper
• Hypoxia and salinity constrain the sediment microbiota-mediated N removal potential in an estuary: A multi-trophic interrelationship perspective.

  2023cited by this paper
• Influences of hydrodynamics on microbial community assembly and organic carbon composition of resuspended sediments in shallow marginal seas.

  2023cited by this paper
• The distinct phases of fresh-seawater mixing intricately regulate the nitrogen transformation processes in a high run-off estuary: Insight from multi-isotopes and microbial function analysis.

  2023cited by this paper
• Inferring ecological selection from multidimensional community trait distributions along environmental gradients

  2023cited by this paper
• Hydraulic characteristics in channel confluence affect the nitrogen dynamics through altering interactions among multi-trophic microbiota.

  2023cited by this paper
• Lowland river sinuosity on Earth and Mars set by the pace of meandering and avulsion

  2023cited by this paper
• Microbial community structure and denitrification responses to cascade low-head dams and their contribution to eutrophication in urban rivers.

  2023cited by this paper
• Differentiation strategies for planktonic bacteria and eukaryotes in response to aggravated algal blooms in urban lakes

  2023cited by this paper
• Microbial network complexity drives non-linear shift in biodiversity-nutrient cycling in a saline urban reservoir.

  2022cited by this paper
• Reconciling disagreement on global river flood changes in a warming climate

  2022cited by this paper
• Impact of an artificial chute cutoff on the river morphology and flow structure in Sipaikou area of the Upper Yellow River

  2021cited by this paper
• Role of dams in reducing global flood exposure under climate change

  2021cited by this paper
• Recovery of freshwater microbial communities after extreme rain events is mediated by cyclic succession

  2021cited by this paper
• How complementarity and selection affect the relationship between ecosystem functioning and stability.

  2021cited by this paper
• Microbial community coalescence: does it matter in the Three Gorges Reservoir?

  2021cited by this paper
• Hydrodynamic disturbance controls microbial community assembly and biogeochemical processes in coastal sediments

  2021cited by this paper
• Soil multitrophic network complexity enhances the link between biodiversity and multifunctionality in agricultural systems

  2021cited by this paper
• Nitrogen cycling processes and the role of multi-trophic microbiota in dam-induced river-reservoir systems.

  2021cited by this paper
• Determination of the direct and indirect effects of bend on the urban river ecological heterogeneity.

  2021cited by this paper
• Species richness stabilizes productivity via asynchrony and drought-tolerance diversity in a large-scale tree biodiversity experiment

  2021cited by this paper
• Microbial river-to-sea continuum: gradients in benthic and planktonic diversity, osmoregulation and nutrient cycling

  2021cited by this paper
• Particulate organic matter as causative factor to eutrophication of subtropical deep freshwater: Role of typhoon (tropical cyclone) in the nutrient cycling.

  2020cited by this paper
• Trophic pyramids reorganize when food web architecture fails to adjust to ocean change

  2020cited by this paper
• On the sensitivity of food webs to multiple stressors.

  2020cited by this paper
• The evolution of trait variance creates a tension between species diversity and functional diversity

  2020cited by this paper
• Exploring the temporal variability of a food web using long‐term biomonitoring data

  2019cited by this paper
• Linkages between flow regime, biota, and ecosystem processes: Implications for river restoration

  2019cited by this paper
• Cascade dam impoundments restrain the trophic transfer efficiencies in benthic microbial food web.

  2019cited by this paper
• Vertical water renewal in a large estuary and implications for water quality.

  2019cited by this paper
• Bend-induced sediment redistribution regulates deterministic processes and stimulates microbial nitrogen removal in coarse sediment regions of river.

  2019cited by this paper
• Tropical forest conversion to rubber plantation affects soil micro- & mesofaunal community & diversity

  2019cited by this paper
• Soil microbiomes with distinct assemblies through vertical soil profiles drive the cycling of multiple nutrients in reforested ecosystems

  2018cited by this paper
• Predator and prey biodiversity relationship and its consequences on marine ecosystem functioning—interplay between nanoflagellates and bacterioplankton

  2018cited by this paper
• The microbial nitrogen-cycling network

  2018cited by this paper
• Climate warming reduces the temporal stability of plant community biomass production

  2017cited by this paper
• Dual Isotope Measurements Reveal Zoning of Nitrate Processing in the Summer Changjiang (Yangtze) River Plume

  2017cited by this paper
• Competitive network determines the direction of the diversity–function relationship

  2017cited by this paper
• Plant functional diversity drives niche‐size‐structure of dominant microbial consumers along a poor to extremely rich fen gradient

  2014cited by this paper
• Biodiversity and Ecosystem Functioning: Current Knowledge and Future Challenges

  2001cited by this paper

• Decoupling of Biodiversity and Network Stability in Sediment-Laden Rivers: A Cross-Regional Analysis of Multitrophic Communities in the Yellow River.

  2026cites this paper
• Nutrient loading induces bistability in microeukaryotes of pump station forebay sediments with interdomain regulation of nitrogen cycling

  2026cites this paper
• Responses of Fungal and Bacterial Communities in Summer Maize Rhizosphere Soil to Brackish Water Sprinkler Irrigation With Different Mineralization Degrees and Soil Environmental Factors

  2026cites this paper
• Hydrodynamics regulates microbial degradation of microplastics by modulating bottom-up and top-down effects in a river-lake confluence zone.

  2025cites this paper