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where v
A
v
z
are velocity projections of motion in the environment; Q
A
is the
input of biogenic elements to A resulting from the decomposition of detritus
Q
A
¼
d
n
R
D
v
A
u
;
k
;
with R
D
¼
l
A
B
7
;
ʴ
n
is the content of nutrients in the dead organic
ʼ
A
is the rate of decomposition of detritus into the environment A; k
2
matter;
is the
kinematical coef
ʴ
1
is the velocity of nutrient assimi-
lation by the photosynthetic process per unit of the phytoplankton production;
cient of vertical diffusion;
A
1
e
is
the proportional part of the
-th radionuclide which is chemically analogous to B
6,A
on substrate A; H
1
is the rate of input
ʵ
fl
flow of the
ʵ
-th radionuclide; Ti
i
is the rate of
exchange with the environment;
ˁ
1
is the part of the biomass losses due to exchange
which transform into nutrients (Legendre and Legendre 1998); and
ʲ
V
is the
upwelling velocity. Equation (
6.1
) is the basic element of block NM.
As a basic scheme for the
flow of nutrients in the water, the scheme proposed by
Krapivin (1996) is accepted as corrected for the conditions of the Arctic Basin by
Legendre and Legendre (1998). It is supposed that the spatial distribution of
upwelling zones is given with seasonal variations. Block NUM realizes this scheme
in reference to the current structure of the upwelling regions.
The irradiance E
0
arrives at the surface of
fl
. The estimate of E
0
is obtained from
monitoring or is calculated from the climatic model. The
Ω
flow of E
0
is attenuated by
snow, ice and water according to the scheme of Table
6.4
. In each cell
fl
X
ij
the
structure of these layers is changed corresponding to the time of year. Within each
layer, the attenuation of the irradiance with the depth is described by an exponential
model (Legendre and Krapivin 1992). The parameters
ʲ
A
are functions of
the salinity, turbidity, temperature, and biomass. The form of this dependence is
given as a scenario or else the standard functions are used (block IM).
The phytoplankton production R
pA
in the environment A is a function of the solar
radiation E
A
, the concentration of nutrients n
A
, the temperature T
A
, the phyto-
plankton biomass p
A
, and the concentration of pollutants
a
A
and
n
A
. There are many
models for the description of the photosynthesis process (Legendre and Legendre
1998; Legendre and Krapivin 1992). For the description of this function in the
present study, the equation of the Michaelis-Menten type is used (block MFB):
R
pA
¼ a
A
k
I
p
A
;
max
=
E
A
þ
K
I
ð
6
:
3
Þ
where K
I
5R
pA
;
max
, and p
A
;
max
is the
maximum quantum yield (Legendre and Legendre 1998). The coef
is the irradiance level at which R
pA
¼ 0
:
ects
the dependence of the phytoplankton production on the environment temperature
T and the concentration of nutrients B
6,A
. The block MFB realizes the following
equation for the calculation of a
A
:
cient a
A
re
fl
ðÞ
1
þ
B
2
;
A
a
2
B
6
;
A
a
A
¼ a
1
K
0
T
;
ð
6
:
4
Þ
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