Drivers of water level fluctuations and hydrological exchange between groundwater and surface water at the lowland River Spree (Germany): field study and statistical analyses.

摘要: Hydrological exchange processes in the floodplain of a lowland groundwater-surface water system with emphasis to hyporheic zone are studied on basis an experimental site surrounded by oxbow and current bed river Spree. Water levels were collected 12 piezometers 2 recording stage gauges 300-m long transect throughout 1-year-period. Due clogging hydraulic contact between adjacent aquifer is marginal. Fluctuating cause alternation infiltration exfiltration. Most time groundwater flux directed into Spree while events usually short. The largest event 1-year-period reached about 4 m aquifer. On principal component analysis two major controlling level fluctuations identified. first responsible for 70% stands dampening delay gauge spreading second explaining 20% recharge due precipitation events. In lower reaches extended floodplains, mainly controlled thus, hydrological conditions upstream reaches. contrast local minor importance upslope completely unimportant. A cross correlation times series different was used calculate lag pressure at locations resulted propagation 1550 d−1 effective velocity 1000 smaller. Fast should not be misinterpreted as fast flow velocities special care necessary modelling such data sets since most models cannot cope head fluctuations. Copyright © 2009 John Wiley & Sons, Ltd.