溶解的有机质(DOM)在驱动生物地球化学功能的发展中起着至关重要的作用。为他们的可持续康复奠定基础。然而,在经历长期直接植被恢复的此类地点中,分子水平上的DOM组成及其与微生物群落的相互作用仍然知之甚少。这项研究调查了DOM的化学多样性及其与四种植物的根际和非根际渣中细菌群落的关联(Arundodonax,构树,福日隐虫草,和刺槐)在锌冶炼渣现场种植了10年。结果表明,脂质的相对丰度从18%下降到5%,虽然单宁和木质素/CRAM样物质的相对丰度从4%增加到10%,从44%增加到64%,分别。由于保留了顽固的DOM成分,根际渣中有机物的化学稳定性增加,如木质素,芳烃,还有单宁.随着细菌群落的多样性和相对丰度的增加,特别是在变形杆菌内,有更好的利用顽固成分(例如,木质素/CRAM样化合物),但这种利用并非一成不变。此外,观察到特定细菌OTU和DOM分子之间的潜在偏好关联,可能受到重金属生物利用度的刺激。网络分析揭示了细菌群落和DOM分子之间复杂的连通性和强相互作用。DOM分子和细菌群落之间的这些特定相互作用使得能够适应炉渣环境的恶劣条件。总的来说,这些发现为长期恢复植被的锌冶炼渣站点在分子水平上的DOM化学多样性转化提供了新的见解。这些知识可以作为制定直接重新植被战略以可持续恢复金属冶炼渣场的重要基础。
Dissolved organic matter (DOM) plays a critical role in driving the development of biogeochemical functions in revegetated metal smelting slag sites, laying a fundamental basis for their sustainable rehabilitation. However, the DOM composition at the molecular level and its interaction with the microbial community in such sites undergoing long-term direct revegetation remain poorly understood. This study investigated the chemodiversity of DOM and its association with the bacterial community in the rhizosphere and non-rhizosphere slags of four plant species (Arundo donax, Broussonetia papyrifera, Cryptomeria fortunei, and Robinia pseudoacacia) planted at a zinc smelting slag site for 10 years. The results indicated that the relative abundance of lipids decreased from 18 % to 5 %, while the relative abundance of tannins and lignins/CRAM-like substances increased from 4 % to 10 % and from 44 % to 64 % in the revegetated slags, respectively. The chemical stability of the organic matter in the rhizosphere slag increased due to the retention of recalcitrant DOM components, such as lignins, aromatics, and tannins. As the diversity and relative abundance of the bacterial community increased, particularly within the Proteobacteria, there was better utilization of recalcitrant components (e.g., lignins/CRAM-like compounds), but this utilization was not invariable. In addition, potential preference associations between specific bacterial OTUs and DOM molecules were observed, possibly stimulated by heavy metal bioavailability. Network analysis revealed complex connectivity and strong interactions between the bacterial community and DOM molecules. These specific interactions between DOM molecules and the bacterial community enable adaptation to the harsh conditions of the slag environment. Overall, these findings provide novel insights into the transformation of DOM chemodiversity at the molecular level at a zinc smelting slag sites undergoing long-term revegetation. This knowledge could serve as a crucial foundation for developing direct revegetation strategies for the sustainable rehabilitation of metal smelting slag sites.