Research
| Title： | Plant growth-promoting rhizobacteria enhance the recovery of submerged macrophytes and increase the absorption of greenhouse gases |
|---|---|
| First author： | Zhu, Jianglong; Wu, Yuman; Zhang, Guofeng; Wang, Chen; Zhu, Yuxin; Li, Zhebo; Liu, Panjie; Zhang, Yi; Xu, Dong; Wang, Chuan |
| Journal： | WATER RESEARCH |
| Years： | 2025 |
| DOI： | 10.1016/j.watres.2025.124562 |
| Abstract： | Submerged macrophyte-dominated aquatic ecosystems are recognized for their ability to improve water quality and reduce greenhouse gas (GHG) emissions. However, the restoration of submerged macrophytes in freshwater ecosystems is frequently limited by low light availability. This study aimed to explore the effects of PGPR on GHG fluxes at the water-air interface and plant restoration of five submerged macrophytes-Vallisneria denseserrulata, Potamogeton wrightii, Hydrilla verticillata, Ceratophyllum demersum, and Myriophyllum spicatum-under low light stress (10 % of natural light intensity). Four PGPR strains-Pseudomonas vancouverensis (M1), Pseudomonas plecoglossicida (C2), Enterobacter ludwigii (E15), and a tri-strain consortium (Mix: M1 + C2 + E15)-were applied to macrophyte rhizospheres. Annual-scale observations revealed that submerged macrophytes shifted the GHG at the water-air interface from net emission to net absorption. PGPR inoculation significantly enhanced the recovery of submerged macrophytes under combined low light stress and biological grazing pressure, with strain C2 showing the best effect in post-grazing regeneration. PGPR inoculation primarily increased the annual cumulative CO2 absorption, amplifying the water-air interface carbon sink by 19 %-457 %. The Mix consortium exhibited the highest CO2 uptake capacity across all species, with V. denseserrulata inoculated with Mix achieving the lowest global warming potential (GWP:-9005.49 +/- 892.23 g CO2-eq m-2). This study shows that PGPR inoculation promotes submerged macrophyte restoration and carbon sequestration in light-limited freshwater ecosystems, providing a promising strategy for lake rehabilitation under global carbon reduction targets. |
