引黄入晋工程对汾河水体真核微生物群落的影响
- Effect of Yellow River diversion project on eukaryotic microbial community in Fenhe River
- 基金项目：国家自然科学基金项目（面上项目，重点项目，重大项目）
- 摘要：引黄入晋工程是缓解山西省水资源短缺，改善其生态环境的重大战略工程。真核微生物在维持水质稳定方面发挥着重要作用，然而，关于其群落动态变化以及导致这些变化的具体因素的研究相对较少。该研究基于18S rRNA高通量测序技术，分别于间歇期与引黄期在汾河的受水河段和未受水河段5个采样点采样，对水体真核微生物群落及其丰富（AT）和稀有（RT）群落动态进行了分析。结果表明，采样时间和样点均显著影响了真核微生物群落的多样性指数，引黄期真核微生物多样性较低；相较于间歇期，引黄期绿藻门（Chlorophyceae）减少，Ulvophyceae和节肢动物门（Arthropoda）增加，共生网络较为简单，协同性增强，RT群落在网络中比例更高，异养生物在关键物种中比例增加；地理与环境因素共塑真核微生物群落动态，Bray-Curtis相似性与环境地理距离的相关性发现引黄期样点间空间异质性增强，AT与RT群落呈相似的距离衰减，AT群落受环境影响更小；冗余分析（RDA）表明间歇期和引黄期群落的主要驱动因素分别是电导率和地理距离；随机森林（Random Forest）结果显示与RT群落相比，AT群落与环境因子的相关性更弱，表明AT 群落对外部环境的干扰通常具有较强的抵抗力和恢复力，对维持生态系统功能和稳定性发挥重要作用。综合结果表明，该引水工程在实施过程中，对汾河水生态系统的整体稳定性和生物多样性未引发显著的生态扰动。
- Abstract：The Yellow River Water Introduction Project in Shanxi Province is a major strategic engineering project to alleviate water shortage and improve the ecological environment. Eukaryotic microorganisms play important roles in maintaining water quality, but research on the dynamic changes of their community is limited. Based on 18S rRNA high-throughput sequencing technology, the eukaryotic microbial communities and the dynamics of abundant (AT) and rare (RT) communities were analyzed at 5 sampling points in the flooded and unflooded reaches of Fenhe River during intermittent and Yellow River diversion periods.The results show that the sampling time and points significantly affect the diversity index of eukaryotic microbial communities. Compared to the intermittent period, during the Yellow River water introduction period, the diversity of eukaryotic microorganisms was lower, accompanied by a decrease in Chlorophyceae, an increase in Ulvophyceae and Arthropoda, a simplified cooperative network, enhanced synergy, and an improved proportion of heterotrophic species among the key species. The geographic and environmental factors jointly shape the dynamics of eukaryotic microbial communities. The correlation between Bray-Curtis similarity and environmental geographic distance reveals that the spatial heterogeneity of sampling points has increased during the Yellow River water introduction period, and the AT and RT communities show similar distance decay. The AT community is less affected by the environment. The redundancy analysis (RDA) shows that the main driving factors of the community in the intermittent period and the Yellow River water introduction period are Conductivity and Geographic Distance, respectively. The results of the random forest (Random Forest) show that the correlation between the AT community and environmental factors is weaker than that of the RT community, indicating that the AT community has stronger resistance and resilience to external environmental interference and plays an important role in maintaining ecosystem function and stability. The overall results show that the water diversion project has not caused significant ecological disturbances to the overall stability and biodiversity.
