作者：Wu, F., An, S., Liu, J., Lu, Y., He, H., Chang, X., Zhang, S., Xing, P., Li, K. & Du, Y.

Lake eutrophication is a widespread challenge, and macrophyte reconstruction has been shown as an effective strategy for restoring shallow eutrophic lakes. However, the impacts of macrophyte on the sedimentary carbon sequestration and underlying mechanisms remain poorly understood. Here, we conducted a year-long field investigation to compare carbon dynamics in macrophyte-restored and unrestored areas within a typical urban lake, analyzing physicochemical properties, organic matter composition, and microbial community structure. Compared to the unrestored areas, macrophyte-restored areas showed similar to 80% higher total sedimentary carbon, along with lower sediment pH and increased aromaticity (SUVA254) and humification (HIX) of both watersoluble and alkaline-extractable organic matter. In addition, sediments in the restored areas supported a higher microbial richness and a microbial community more enriched in Alphaproteobacteria. Partial least squares-path modeling revealed that enhanced carbon sequestration by macrophyte restoration was primarily driven by shifts in sedimentary organic matter composition. Reduction in labile substrates (e.g., peptides and protein-like components), coupled with lower sediment pH, shifted the microbial community toward taxa associated with enhanced carbon persistence (Alphaproteobacteria). Overall, our results demonstrate that macrophyte restoration enhances sediment carbon sequestration through initiating shifts in sedimentary organic matter composition that subsequently restructure organic matter-microbe-environment interactions. This study provides direct evidence that macrophyte restoration, as a nature-based solution widely applied in shallow eutrophic lakes, can contribute to carbon sequestration beyond its well-recognized role in water quality improvement.

湖泊富营养化是一个普遍性难题，而水生植物重建已被证明是修复浅水富营养化湖泊的有效策略。然而，水生植物对沉积物碳封存的影响及其潜在机制仍知之甚少。本研究在一个典型城市湖泊中开展了为期一年的野外调查，比较了水生植物恢复区与未恢复区的碳动态，分析了理化性质、有机质组成和微生物群落结构。与未恢复区相比，水生植物恢复区的沉积物总碳高出约80%，同时沉积物pH更低，水溶性有机质和碱提有机质的芳香度（SUVA₂₅₄）和腐殖化指数（HIX）均更高。此外，恢复区沉积物具有更高的微生物丰富度，其微生物群落中α-变形菌纲更为富集。偏最小二乘路径模型分析表明，水生植物恢复所增强的碳封存主要由沉积物有机质组成的变化所驱动。易利用底物（如肽类和类蛋白组分）的减少，加上较低的沉积物pH，使微生物群落转向与碳持久性增强相关的类群（α-变形菌纲）。总体而言，我们的研究结果证明，水生植物恢复通过引发沉积物有机质组成的变化，进而重塑有机质–微生物–环境之间的相互作用，从而增强了沉积物碳封存。本研究为水生植物恢复这一在浅水富营养化湖泊中广泛应用的基于自然的解决方案，提供了直接证据，表明其除了公认的水质改善作用外，还有助于碳封存。

（来源：Water Research 2026  DOI: 10.1016/j.watres.2026.125658）