Operational Diagnostics, Estimation of the Scale of Damage and Aftermath Reduction of the Stressful Natural Processes - New Ecoinformatics Tools in Environmental Science: Applications and Decision-making - page 760

Table 9.17 An evaluation of the ESECEZ system ef ciency on the base of spatial reconstruction
of water salinity in Nuoc Ngot Lagoon
Controlling
sites

Water depth
level

Measured water
salinity (ppm)

Simulated water
salinity (ppm)

Error
(%)

2 Surface 30.1 33.1 10

Middle 31.3 27.5 12

Near-bottom 32.4 28.5 12

4 Surface 27.4 30.1 10

Middle 30.2 33.2 10

Near-bottom 32.2 28.0 13

6 Surface 24.9 28.4 14

Middle 26.6 30.3 14

Near-bottom 29.6 33.7 14

8 Surface 24.2 22.7 6

Middle 26.8 22.5 16

Near-bottom 28.4 26.4 7

10 Surface 28.5 25.6 10

Middle 30.9 27.2 12

Near-bottom 32.4 28.5 12

Spatial structure of hydrologic and abiotic components for Nuoc Ngot Lagoon
was reconstructed by means of the ESECEZ system on the basis of the in situ
measurements in the control points 1, 3, 5, 7, 9 and the results obtained were
compared with measurements in the control points 2, 4, 6, 8, 10.

￿

Particular results of prognosis of some characteristics of the lagoon were
assessed taking into consideration of the in situ measurements in all control
points during the prognosis time (Table 9.18 ).

￿

General concept about the ESECEZ system capability to forecast the water
quality in Nuoc Ngot Lagoon gives the results shown in Fig. 9.20 . Simulation
experiments with the ESECEZ system use show that all processes in the lagoon
depend on its hydrophysical and physico-chemical interactions with South-China
Sea where input data about anthropogenic impacts are available. In this case, the
lagoon control can be realized using the ESECEZ system with input data obtained
only in the lagoon mouth

ʓ (controlling site 1) with time intervals according to

Fig. 9.22 (Table 9.19 ).
Figures 9.23 and 9.24 show phase portraits of the lagoon taking into consider-
ation of its coordinates turbidity/salinity and salinity/water level variation. It was
found that there exists a signi

cant maximum of the dependence between the
turbidity and salinity. This maximum obtains its minimal value in the mouth of the
river flowed to the lagoon and its maximal value at the lagoon centre. The corre-

lation between the salinity and the lagoon level variation has more complex
character. Water salinity in the lagoon mouth weakly depends on the change of its

fl