Article 1 by Heejung Kim and Kang-Kun Lee* Effect of vertical flow exchange on microbial community dis- tributions in hyporheic zones School of Earth and Environmental Sciences, Seoul National University, Seoul 08826, Republic of Korea; *Corresponding author, E-mail:
[email protected] (Received: November 2, 2018; Revised accepted: January 6, 2019) https://doi.org/10.18814/epiiugs/2019/019001 The effect of the vertical flow direction of hyporheic flux advance of hydrodynamic modeling has improved research of hydro- on the bacterial community is examined. Vertical velocity logical exchange processes at the hyporheic zone (Cardenas and Wil- change of the hyporheic zone was examined by installing son, 2007; Fleckenstein et al., 2010; Endreny et al., 2011). Also, this a piezometer on the site, and a total of 20,242 reads were zone has plentiful micro-organisms. The hyporheic zone constituents analyzed using a pyrosequencing assay to investigate the a dynamic hotspot (ecotone) where groundwater and surface water diversity of bacterial communities. Proteobacteria (55.1%) mix (Smith et al., 2008). were dominant in the hyporheic zone, and Bacteroidetes This area constitutes a flow path along which surface water down wells into the streambed sediment and groundwater up wells in the (16.5%), Actinobacteria (7.1%) and other bacteria phylum stream, travels for some distance before eventually mixing with (Firmicutes, Cyanobacteria, Chloroflexi, Planctomycetesm groundwater returns to the stream channel (Hassan et al., 2015). Sur- and unclassified phylum OD1) were identified. Also, the face water enters the hyporheic zone when the vertical hydraulic head hyporheic zone was divided into 3 points – down welling of surface water is greater than the groundwater (down welling).