Need to quantitatively relate Hydrodynamics physics Transport Chemistry, e'g', N Ecology Biology in

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Need to quantitatively relate Hydrodynamics
(physics) Transport (Chemistry, e.g., N)Ecology
(Biology)inSpace Time
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• Hydrodynamics
• Transport
• ?c/?t ?(ui c/?xi ) ?(Dij ?c/?xj )/?xi
• ?sources ? Sinks
• Ecology

Circulation
Mixing
Exposure Concentration duration
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Transport Time Scales
Q1
Monsen et al. (2002)
All originated from physical properties of the
water body and chemical properties of
constituents, but not biology/ecology
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Local Residence Time (LRT) A Measure of Transport
Relates to concentration at a specific location
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Greenwich Bay
LRT
Narragansett Bay
Greenwich Cove
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Providence-Seekonk River
Pawcatuck River
LRT
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Local Effect Time (LET)A Measure of
Susceptibility
Relates to concentration and biology at a
specific location
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Example 1 LET from low to high flow
Hours
A
Unhappy
Zostera
Ulva
B
Happy to unhappy
Happy
C
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Example 2 LET from high to low flow
Hours
Zostera
A
Happy
Ulva
B
Unhappy to happy
Happy to unhappy
Unhappy
C