Stream-aquifer interactions and hyporheic exchange in gaining and losing sinuous streams

摘要: [1] The irregular planform morphology of rivers leads to formation hyporheic zones along its banks. This study investigates how exchange in stream banks, whose is idealized as sinusoidal, affected by net gains from and losses water the adjacent aquifer. These effects are studied via numerical modeling groundwater flow sinuous channels across a broad range sinuosity gain/loss magnitude. Hyporheic zone areas fluxes both decrease exponentially with increasing magnitude gain or loss relative case where has no flux (neutral). Residence time through also decreases The become constrained near apex bends, indicating that these could be hot spots for mixing biogeochemical processing. smaller more prone area reduction while very able maintain even under largely losing gaining conditions. Equations fitted suite simulation results allow prediction flux, area, residence on basis aquifer hydraulic conductivity, channel sinuosity, ratio along-valley across-valley mean head gradients.