Modeling Concepts - Coastal Lagoons: Ecosystem Processes and Modeling for Sustainable Use and Development - page 251

1.0

Leaky lagoon with
high fresh run-off
influence

Leaky lagoon with
high marine
influence

0.1

5

4

2

0.01

1

6

3

Choked lagoon
with high fresh
run-off influence

Choked lagoon
with high marine
influence

0.001

0 0.2 0.4 0.6 0.8 1.0 1.2

Salt ratio (S lag /S sea ), dimensionless

FIGURE 6.9 Location of some selected lagoons (Table 6.7) on the morphometric-hydrolog-
ical diagram.

The next step in classifying a lagoon based on its hydrological features is to
position it on a morphometric-hydrological diagram (Figure 6.9), where the control-
ling parameters are the salt ratio ( ) and the lagoon restriction parameter p r
(Table 6.7). The salt ratio relates , which are the annual average salinity
inside the lagoon and in the adjacent marine area, respectively. For example, this
diagram (Figure 6.9) shows that the Curonian, the Odra, and the Vistula lagoons
belong to the geomorphic class of choked lagoons; that the Vistula Lagoon is signif-
icantly influenced by the adjacent sea; and that the Curonian Lagoon is completely

(avg ) (avg )

s s

lag

sea

(avg )

and

(avg )

s s

lag sea

TABLE 6.7
Mean Annual Values of the Salt Ratio and Parameter of Lagoon Restriction
for Some Selected Lagoons

N Lagoon Name Salt Ratio ( s lag / s sea ) Restriction Ratio ( p r )

1 Curonian Lagoon 0.007 0.008

2 Odra Lagoon 0.286 0.012

3 Vistula Lagoon 0.529 0.004

4 Grande-Entrée Lagoon 1 0.021

5 Ria Formosa Lagoon 1 0.046

6 Mar Menor Lagoon 1.081 0.005