summer period from June to September and the minimum in the winter months.
Intermediate values of these parameters match the spring and autumn period.
19.1.3 Contribution of the Upward Flux of Phosphorus
to the Total of Its Income into the Zone
of Photosynthesis
According to the concept of the “new” and the regeneration products (Dugdale and
Goering 1967; Eppley and Peterson 1979) at steady state between the elements of
the biotic nitrogen balance in the photic layer of open ocean areas supported by a
dynamic equilibrium. Upward flux of nitrates entering the surface water by physical
processes is equivalent to sedimentation flux of particulate organic nitrogen and is
equal to the rate of uptake of nitrate by phytoplankton.
Assuming that within the selected scale averaging observed stationary condition,
calculated upward flux of phosphorus corresponds to the “new” production, its flux
regeneration – regenerative production, and the value of f-ratio (the proportion of
“new” products) – F P index the upward contribution of phosphorus flux calculated
using the formula:
F P ¼ V Á 100%= E þ V
ð
Þ
ð19:1Þ
Where the V – ascending E – regenerative flux of phosphates, mg-atP m
À2 day
À1 .
Seasonal variability of the upstream contribution to the total income of phosphorus in the photosynthesis zone was considered on the basis of monthly averages
of the F P (Fig. 19.2), the value of which vary from 10 to 70% during the year. The
maximum values are observed during the period from December to March and in
July and August, they are reduced to a minimum. In spring and autumn, the
magnitude of this figure is an average of 30%. In an average year the upward flux
of inorganic phosphorus provides – 37% of its total income in the photic layer.
It is known that increasing the share of “new”/export production typical of the
area of the ocean or the seasons of the year with an intensive vertical mixing of
waters is accompanied by the accumulation of algal biomass and the increase in
primary production (Eppley and Peterson 1979; Falkowski et al. 2003). According
to our estimates, in the deepwater area of the Black Sea change of upward flux of
phosphate is mainly determined by the change in the coefficient of vertical turbulent diffusion (K Z ). A fivefold increase in the value of K Z in winter compared to
July–August, in average corresponds to a similar increase in the rate of income of
phosphate (Fig. 19.2a). But significant change in the phosphate concentration
gradient throughout the year is not established (Krivenko and Parkhomenko
2015). Only in winter, when K Z was adopted as a constant, change in the concentration gradients of phosphorus defined by two-fold change of upward flux in the
period from December to March. The intensity of mixing of surface water also
342
A.V. Parkhomenko
Intermediate values of these parameters match the spring and autumn period.
19.1.3 Contribution of the Upward Flux of Phosphorus
to the Total of Its Income into the Zone
of Photosynthesis
According to the concept of the “new” and the regeneration products (Dugdale and
Goering 1967; Eppley and Peterson 1979) at steady state between the elements of
the biotic nitrogen balance in the photic layer of open ocean areas supported by a
dynamic equilibrium. Upward flux of nitrates entering the surface water by physical
processes is equivalent to sedimentation flux of particulate organic nitrogen and is
equal to the rate of uptake of nitrate by phytoplankton.
Assuming that within the selected scale averaging observed stationary condition,
calculated upward flux of phosphorus corresponds to the “new” production, its flux
regeneration – regenerative production, and the value of f-ratio (the proportion of
“new” products) – F P index the upward contribution of phosphorus flux calculated
using the formula:
F P ¼ V Á 100%= E þ V
ð
Þ
ð19:1Þ
Where the V – ascending E – regenerative flux of phosphates, mg-atP m
À2 day
À1 .
Seasonal variability of the upstream contribution to the total income of phosphorus in the photosynthesis zone was considered on the basis of monthly averages
of the F P (Fig. 19.2), the value of which vary from 10 to 70% during the year. The
maximum values are observed during the period from December to March and in
July and August, they are reduced to a minimum. In spring and autumn, the
magnitude of this figure is an average of 30%. In an average year the upward flux
of inorganic phosphorus provides – 37% of its total income in the photic layer.
It is known that increasing the share of “new”/export production typical of the
area of the ocean or the seasons of the year with an intensive vertical mixing of
waters is accompanied by the accumulation of algal biomass and the increase in
primary production (Eppley and Peterson 1979; Falkowski et al. 2003). According
to our estimates, in the deepwater area of the Black Sea change of upward flux of
phosphate is mainly determined by the change in the coefficient of vertical turbulent diffusion (K Z ). A fivefold increase in the value of K Z in winter compared to
July–August, in average corresponds to a similar increase in the rate of income of
phosphate (Fig. 19.2a). But significant change in the phosphate concentration
gradient throughout the year is not established (Krivenko and Parkhomenko
2015). Only in winter, when K Z was adopted as a constant, change in the concentration gradients of phosphorus defined by two-fold change of upward flux in the
period from December to March. The intensity of mixing of surface water also
342
A.V. Parkhomenko