Download - Neuse Estuary Eutrophication Model
Neuse Estuary Eutrophication
ModelP a m lico S o u n d
E x ch an ge
A tm o sp h ere
L oa ding s E x ch an ge
R ivers, C reek s ,G ro u n d w a ter
O rg a n ic M a tter
D isso lvedO x yg en
A lg a eN euse R iver E stu ary
N u tr ien tsIn o rg a n icS ed im en ts
B e n th ic O r g an ic M a tte r
In o rg a n icC a rb o n
Sedim entE x ch an ge
V erticalM ixing
E stu ar in eC irculatio n
G row th/M orta lity /R ecyc ling
Sedim ents
NitrogenInputs Cause and Effect
RelationshipsCause and Effect
Relationships
Frequency of Hypoxia
Duration of Stratification
HarmfulAlgal Blooms
Carbon Production
SedimentOxygenDemand
RiverFlow
AlgalDensity
ChlorophyllViolations
Number ofFishkills
FishHealth
ShellfishAbundance
NeuBERNBayes Net
Estuary Model
“Given (conditional on) a 30%reduction in nitrogen loading, what is
the probability of an algal bloom?”
p(ALG|30% N-load reduction) = ?
Model proposed by Chen and Orlob (1972)
1,22211111111 )( FVCVCMsRQC
dt
dCEAQC
dt
dVCin
Phytoplankton (Algae) Mass Balance
(equation from the model proposed by Chen and Orlob (1972))
where: V = segment volume (m3) C1 = phytoplankton concentration (g/m3) Q = flow volume (m3/t) E = diffusion coefficient (m2/t) A = segment surface/bottom area (m2) µ1 = phytoplankton growth rate (t-1) R1 = phytoplankton respiration rate (t-1) s1 = phytoplankton settling rate (t-1) M1 = phytoplankton mortality rate (t-1) µ2 = zooplankton growth rate (t-1) C2 = zooplankton concentration (g/m3) F2,1 = fractional feeding preference
For phytoplankton settling, another common approach is to treat
phytoplankton settling as a velocity term with an areal loss:
(Chapra and Reckhow 1983, Chapter 14)
phytoplankton settling (mass/time) = v1AC1
Parameter Selection Example: Phytoplankton Settling
Table 1. Phytoplankton settling velocities (Bowie et al. 1985)