State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Science, Beijing 100012, PR China; State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, PR China.
State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Science, Beijing 100012, PR China.
Environ Res. 2023 Jun 15;227:115710. doi: 10.1016/j.envres.2023.115710. Epub 2023 Mar 16.
Vegetation restoration projects can not only improve water quality by absorbing and transferring pollutants and nutrients from non-vegetation sources, but also protect biodiversity by providing habitat for biological growth. However, the mechanism of the protistan and bacterial assembly processes in the vegetation restoration project were rarely explored. To address this, based on 18 S rRNA and 16 S rRNA high-throughput sequencing, we investigated the mechanism of protistan and bacterial community assembly processes, environmental conditions, and microbial interactions in the rivers with (out) vegetation restoration. The results indicated that the deterministic process dominated the protistan and bacterial community assembly (94.29% and 92.38%), influenced by biotic and abiotic factors. For biotic factors, microbial network connectivity was higher in the vegetation zone (average degree = 20.34) than in the bare zone (average degree = 11.00). For abiotic factors, the concentration of dissolved organic carbon ([DOC]) was the most important environmental factor affecting the microbial community composition. [DOC] was lower significantly in vegetation zone (18.65 ± 6.34 mg/L) than in the bare zone (28.22 ± 4.82 mg/L). In overlying water, vegetation restoration upregulated the protein-like fluorescence components (C1 and C2) by 1.26 and 1.01-folds and downregulated the terrestrial humic-like fluorescence components (C3 and C4) by 0.54 and 0.55-folds, respectively. The different DOM components guided bacteria and protists to select different interactive relationships. The protein-like DOM components led to bacterial competition, whereas the humus-like DOM components resulted in protistan competition. Finally, the structural equation model was established to explain that DOM components can affect protistan and bacterial diversity by providing substrates, facilitating microbial interactions, and promoting nutrient input. In general, our study provides insights into the responses of vegetation restored ecosystems to the dynamics and interactives in the anthropogenically influenced river and evaluates the ecological restoration performance of vegetation restoration from a molecular biology perspective.
植被恢复项目不仅可以通过吸收和转移非植被源的污染物和营养物质来改善水质，还可以通过为生物生长提供栖息地来保护生物多样性。然而，植被恢复项目中原生动物和细菌组合过程的机制很少被探索。为了解决这个问题，我们基于 18S rRNA 和 16S rRNA 高通量测序，研究了有（无）植被恢复的河流中原生动物和细菌群落组装过程、环境条件和微生物相互作用的机制。结果表明，确定性过程主导了原生动物和细菌群落的组装（分别为 94.29%和 92.38%），受生物和非生物因素的影响。对于生物因素，微生物网络连接性在植被区（平均度=20.34）高于裸地（平均度=11.00）。对于非生物因素，溶解有机碳（DOC）浓度是影响微生物群落组成的最重要环境因素。DOC 在植被区（18.65±6.34mg/L）显著低于裸地（28.22±4.82mg/L）。在上覆水中，植被恢复使蛋白质样荧光成分（C1 和 C2）分别上调 1.26 倍和 1.01 倍，使陆地腐殖质样荧光成分（C3 和 C4）分别下调 0.54 倍和 0.55 倍。不同的 DOM 成分指导细菌和原生动物选择不同的相互作用关系。蛋白质样 DOM 成分导致细菌竞争，而腐殖质样 DOM 成分导致原生动物竞争。最后，建立结构方程模型来解释 DOM 成分可以通过提供底物、促进微生物相互作用和促进养分输入来影响原生动物和细菌的多样性。总的来说，我们的研究提供了对受人为影响河流中植被恢复生态系统对动态和相互作用的反应的见解，并从分子生物学的角度评估了植被恢复的生态恢复性能。
