为探讨不同水文情景下白洋淀好氧反硝化细菌的演化规律及驱动机制,基于水质调查和高通量测序技术,本研究进行了水质因子分析和好氧反硝化细菌α-多样性分析,物种组成,和网络分析。结果表明,白洋淀水体呈弱碱性,雨季T最高,DO最低,冰冻季节T最低,DO最高。NH4+-N之间存在显著差异,NO2--N,NO3--N,TN,高锰酸盐指数,Fe,不同水文情景下白洋淀水体中锰(P<0.01),不同水文情景下TP差异无统计学意义(P>0.05)。不同水文情景下水体中最大的类别是变形杆菌,相对丰度较高的属是螺旋藻,气单胞菌,假单胞菌,偶氮螺旋菌,和缓生根瘤菌.此外,在需氧反硝化细菌群落中,α-多样性存在显著差异(P<0.001),在冰冻期间微生物群落的丰度最高,以及在干旱和冰冻时期微生物群落的最高多样性和均匀度。根据RDA和Mantel的分析,不同水文情景下植物区系的水质驱动因子不同。枯水期植物区系的水质驱动因子为pH,NO3--N,NO2--N,和高锰酸盐指数;雨季植物区系的驱动因子为pH,T,DO,NO2--N,和TP;正常季节植物区系的驱动因子为NO2--N,Fe,和高锰酸盐指数;冻季植物区系的驱动因子为NO3--N和NOO2--N。网络分析表明,与水质驱动因子相关的物种存在时间差异。与旱季水质驱动因子相关的属为螺旋藻,气单胞菌,和亚足,而与雨季有关的属是磁螺旋藻,假单胞菌,和气单胞菌。与正常季节有关的属是螺旋藻,假单胞菌,和Limnohabitans,与冻结期有关的属是螺旋藻,亚足,和假单胞菌.关键水质因素之间的关系(主要是T,DO,NO3--N,和高锰酸盐指数)和好氧反硝化区系在不同水文情景下随时间逐渐变化。总之,研究不同水文情景下白洋淀好氧反硝化细菌的进化特征及环境因子的驱动机制,为了解自然环境中好氧反硝化细菌的进化机制提供依据。
In order to explore the evolution law and driving mechanism of aerobic denitrification bacteria in Baiyangdian Lake under different hydrological scenarios, based on water quality survey and high-throughput sequencing technology, this study conducted a water quality factor analysis and aerobic denitrification bacteria α-diversity analysis, species composition, and network analysis. The results showed that the water body of Baiyangdian Lake was weakly alkaline, with the highest T and the lowest DO in the rainy season and the lowest T and the highest DO in the freezing season. There were significant differences between NH4+-N, NO2--N, NO3--N, TN, permanganate index, Fe, and Mn in Baiyangdian water under different hydrological scenarios (P < 0.01), and there was no significant difference in TP under different hydrological scenarios (P > 0.05). The largest category in water bodies under different hydrological scenarios was Proteobacteria, and the genera with a higher relative abundance were Magnetospirillum, Aeromonas, Pseudomonas, Azospirillum, and Bradyrhizobium. In addition, within the aerobic denitrifying bacteria community, there were significant differences in α-diversity (P < 0.001), with the highest abundance of microbial communities occurring during the freezing period, and the highest diversity and evenness of microbial communities during the dry and freezing periods. According to the RDA and Mantel analyses, the water quality driving factors of flora were different under different hydrological scenarios. The water quality driving factors of flora in the dry season were pH, NO3--N, NO2--N, and permanganate index; the driving factors of flora in the rainy season were pH, T, DO, NO2--N, and TP; the driving factors of flora in the normal season were NO2--N, Fe, and permanganate index; and the driving factors of flora in the freezing season were NO3--N and NONO2--N. Network analysis showed that there were temporal differences in species related to water quality driving factors. The genera related to water quality driving factors during the dry season were Magnetospirillum, Aeromonas, and Azoarcus, whereas the genera related to the rainy season were Magnetospirillum, Pseudomonas, and Aeromonas. The genera related to the normal season were Magnetospirillum, Pseudomonas, and Limnohabitans, and the genera related to the freezing period were Magnetospirillum, Azoarcus, and Pseudomonas. The relationship between key water quality factors (mainly T, DO, NO3--N, and permanganate index) and aerobic denitrification flora in different hydrological scenarios was gradually changing with time. In conclusion, the study on the evolution characteristics of aerobic denitrification bacteria in Baiyangdian Lake under different hydrological scenarios and the driving mechanism of environmental factors could provide a basis for understanding the evolution mechanism of aerobic denitrification bacteria in the natural environment.