TY - JOUR
T1 - Particle trapping in stratified estuaries
T2 - Consequences of mass conservation
AU - Jay, David A.
AU - Orton, Philip M.
AU - Chisholm, Thomas
AU - Wilson, Douglas J.
AU - Fain, Annika M.V.
PY - 2007/12
Y1 - 2007/12
N2 - Estuarine turbidity maxima (ETM) can retain suspended particulate matter (SPM) through advection, settling, aggregation, and nonlinearities in bed processes. We define a parameter space descriptive of ETM water column particle trapping processes through a scaling analysis of the local and integral SPM balances. There are six primary non-dimensional parameters for the large particles or aggregates that are typically trapped in an ETM. Rouse number P, the ratio of settling velocity WS to the shear velocity U *, describes the material trapped in the ETM in terms of the local vertical balance between vertical mixing and aggregate settling. Advection number A = PΔU/UT scales the landward transport of SPM in terms of flood-ebb velocity difference (ΔU; the internal asymmetry) and maximum tidal current (UT). Supply number SR = PU R/UT defines SPM supply and removal (UR is river flow). Changes in the estuarine inventory of SPM are described in terms of a Trapping Efficiency E, a ratio of peak ETM concentration to fluvial or marine supply concentration. The effects of aggregation and disaggregation in the integral dynamic balance are quantified by a Floc number Θ = Φ/Γ that describes the balance of aggregation (Φ) and disaggregation (Γ). The balance between erosion and deposition at the bed is described by the Erosion number Π = Ψ/Ω, the ratio of erosion (Ψ) to deposition (Ω). The non-dimensional, integral SPM conservation equation is then used to examine steady and unsteady particle trapping scenarios, including adjustments to a change in river flow and to a neap-spring transition in salinity intrusion and stratification.
AB - Estuarine turbidity maxima (ETM) can retain suspended particulate matter (SPM) through advection, settling, aggregation, and nonlinearities in bed processes. We define a parameter space descriptive of ETM water column particle trapping processes through a scaling analysis of the local and integral SPM balances. There are six primary non-dimensional parameters for the large particles or aggregates that are typically trapped in an ETM. Rouse number P, the ratio of settling velocity WS to the shear velocity U *, describes the material trapped in the ETM in terms of the local vertical balance between vertical mixing and aggregate settling. Advection number A = PΔU/UT scales the landward transport of SPM in terms of flood-ebb velocity difference (ΔU; the internal asymmetry) and maximum tidal current (UT). Supply number SR = PU R/UT defines SPM supply and removal (UR is river flow). Changes in the estuarine inventory of SPM are described in terms of a Trapping Efficiency E, a ratio of peak ETM concentration to fluvial or marine supply concentration. The effects of aggregation and disaggregation in the integral dynamic balance are quantified by a Floc number Θ = Φ/Γ that describes the balance of aggregation (Φ) and disaggregation (Γ). The balance between erosion and deposition at the bed is described by the Erosion number Π = Ψ/Ω, the ratio of erosion (Ψ) to deposition (Ω). The non-dimensional, integral SPM conservation equation is then used to examine steady and unsteady particle trapping scenarios, including adjustments to a change in river flow and to a neap-spring transition in salinity intrusion and stratification.
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U2 - 10.1007/BF02841399
DO - 10.1007/BF02841399
M3 - Article
AN - SCOPUS:40949137796
SN - 1559-2723
VL - 30
SP - 1095
EP - 1105
JO - Estuaries and Coasts
JF - Estuaries and Coasts
IS - 6
ER -