受引黄影响的河流沉积物细菌群落季节变化

河流沉积物细菌群落的季节变化对碳、氮循环和水环境演化有明显的影响.然而,受调水干预的河流沉积物细菌群落季节性变化尚不明确.本文基于16S rRNA高通量测序技术,研究了中纬度地区受引黄影响的汾河上游沉积物细菌群落组成、结构和多样性的季节变化.结果表明,在引黄调水干预下受水河流细菌群落的季节性变化仍然显著.夏季温度适宜,河流沉积物细菌群落多样性较冬季高.核心菌群组成和结构随季节变化,然而丛毛单胞菌、黄杆菌、黄单胞菌和红环菌等的优势地位不随季节改变.河水水温和ORP的季节变化显著,是造成河流沉积物细菌群落季节变化的主导因子.水质较差的黄河水引入汾河后导致沉积物细菌群落多样性显著提高.引水对河流沉积物细菌群落的影响在夏季较冬季高20%左右.引黄调水对汾河沉积物细菌群落的影响大于季节变化的影响.

Characteristics of seasonal variation of microbial composition and structure in upstream sediment of the Fen River

Seasonal changes of bacterial communities in river sediments have obvious effects on carbon/nitrogen cycles and water environment evolution. However, the seasonal changes of the bacterial communities affected by water transfer have not been clear yet. Based on the 16S rRNA high-throughput sequencing technique, we studied the seasonal variation of composition, structure and diversity of bacterial communities of river sediments in the upper reaches of the Fen River where the Yellow River water is transferred into. Results show that seasonal changes of bacterial communities are significant even under the influences of the water diversion. The summer temperature is suitable for the majority of bacteria. The bacterial community diversity in river sediments is higher in summer than that in winter. The composition and structure of the dominant bacteria group vary with the seasons, while the dominant communities of Comamonadaceae, Flavobacterium, Xanthomonadaceae and Rhodocyclaceae don''t change. The seasonal variations of river water temperature and oxidation-reduction potential (ORP) are the dominant factors that causes the seasonal change of bacterial communities in the river sediments. The diversity of bacterial communities in sediments increases significantly after the introduction of the Yellow River water with poor quality. The effect of water diversion on the bacterial communities of river sediments is about 20% higher in summer than in winter. The effect of water transfer on the bacterial communities in the Fen River''s sediments is greater than that of seasonal variation.