石家庄市春季景观水体nirS型反硝化细菌群落特征分析

选取石家庄市主城区4个典型景观水体作为研究对象,在对水体水质特征分析的基础上,运用Illumina高通量测序技术对景观水体中的nir S型反硝化细菌种群结构和多样性进行测定,探究春季景观水体水质与nir S型反硝化细菌群落的相互关系.结果表明,4个景观水体中氮素含量为4. 43～13. 83 mg·L-1,氮素污染较严重;基于三维荧光光谱的特征指数分析,4个景观水体均呈现出较强的自生源及弱腐殖质特征; Illumina高通量测序结果表明,不同景观水体中nir S型反硝化细菌大多为变形菌门,在优势菌属上差异显著; unclassified_Bacteria(53. 52%)、假单胞菌(Pseudomonas)(60. 48%)和红杆菌属(Rhodobacter)(46. 94%)分别为裕西、水上和长安公园水体中的优势菌属,unclassified_Bacteria(36. 19%)和unclassified_Proteobacteria(23. 44%)为世纪公园水体中的优势菌属;冗余分析(RDA)结果表明,裕西公园反硝化细菌主要受硝氮、总氮和溶解氧的影响,水上公园反硝化细菌受总磷的影响较大,长安公园反硝化细菌主要受氨氮和亚硝氮的影响,世纪公园反硝化受总磷、亚硝氮和氨氮的影响较大.综上表明,春季不同景观水体的水质以及nir S型反硝化细菌的群落结构差异显著,通过开展景观水体水质、反硝化群落以及影响因素的研究,有助于对城市水系的水质特征以及反硝化群落结构的认识,对基于该水质特征的高效反硝化菌剂的研发具有指导意义.

Community Structure Characteristics of nirS Denitrifying Bacteria of Spring Typical Parkland Waterbodies in Shijiazhuang City

Four typical park water bodies located in the main urban area of Shijiazhuang city were selected to study the relationships between water quality and the community structure and diversity of nirS denitrifying bacteria. The results showed that the nitrogen concentration ranged from 4.43 to 13.83 mg·L^-1 in four park water bodies, which exhibited notable nitrogen pollution characteristics. Based on the characteristic index analysis of three-dimensional fluorescence spectra, the four park water bodies all exhibited strong autochthonous components and low humus characteristics. The results of Illumina high-throughput sequencing indicated that most of the nirS denitrifying bacteria showed significant differences in dominant genus. The unclassified_Bacteria (53.52%), Pseudomonas (60.48%), and Rhodobacter (46.94%) were the dominant bacteria in Yuxi park, Shuishang park, and Chang''an park, respectively. In comparison, unclassified_Bacteria (36.19%) and unclassified_Proteobacteria (23.44%) were the dominant bacteria in Shiji park. Redundancy analysis showed that denitrification bacteria in Yuxi park were mainly affected by nitrate, total nitrogen, and dissolved oxygen; denitrification bacteria in Shuishang park were greatly affected by total phosphorus; denitrification bacteria in Chang ''an park were mainly affected by ammonia and nitrous nitrogen; and denitrification in Shiji park were mainly affected by total phosphorus, nitrite, and ammonia. Overall, the water quality and the community structure of nirS denitrification bacteria exhibited significant differences in park water bodies. Further research could contribute to the understanding of water quality characteristics and the denitrifying community structure of urban water systems, and develop efficient denitrifying bacterial agents.