Saved in:
| Main Authors: | , , , , , , , , , |
|---|---|
| Format: | Artículo científico |
| Language: | en |
| Published: |
Marine pollution bulletin
2026
|
| Subjects: | |
| Online Access: | https://pubmed.ncbi.nlm.nih.gov/41865438/ |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
Table of Contents:
- Ecological water replenishment enhances nitrogen removal potential in coastal wetlands by mediating root exudate composition and sediment chemistry. Zhao, Chunyu Liu, Songlin Wang, Junliang Zhang, Naiqin Lin, Jingqi Liu, Nana Di, Kai Zhang, Donghan Ma, Changwen Liu, Yang Wetlands Nitrogen Plant Roots Denitrification Geologic Sediments China Poaceae Rhizosphere Water Pollutants, Chemical Biodegradation, Environmental Seashore Ecological water replenishment (EWR) is vital for reversing coastal wetland degradation, yet its mechanistic effects on microbial nitrogen (N) removal-particularly via plant root-mediated processes-remain unclear. This study quantifies how EWR drives N removal in Phragmites australis wetlands of China's Yellow River Delta by analyzing rhizosphere soil properties, root exudates, enzymatic activities, functional genes (nirS, anammox 16S rRNA), and N-removal rates pre- and post-EWR. Our results showed that EWR reduced salinity while elevating NO-N (72.3% increasing) and NH₄-N, enhancing denitrification (DNF, 1.54 ± 0.72 μmol·kg·h; 97.5% of total N removal) over anammox (AMX, 0.046 ± 0.02 μmol·kg·h). Critically, EWR upregulated nirS and AMX genes by reshaping root exudates: amino acids (AA) increased as carbon sources and microbial signals, whereas flavonoids and phenolics decreased, alleviating inhibitory to denitrifiers. Structural equation modeling confirmed that EWR controlled the release of root secretions by regulating the environmental factors, and thereby regulates the DNF and AMX process. Consequently, N-removal potential surged 1.3-fold (0.72 vs. 0.54 g N·m·d), purifying 1.86 × 10 t N monthly during EWR periods. We establish that EWR enhances coastal eutrophication control by optimizing root exudate-microbe interactions, providing root exudate profiles and nirS abundance as key ecological indicators for wetland restoration efficacy. This study demonstrated that EWR significantly enhanced the N removal function of wetlands by improving the water-salt environment, increasing substrate supply, and regulating root exudate composition, which EWR substantial practical significance for alleviating coastal eutrophication risks.