420
N. BALAKRISHNAN NAIR AND M. SARASWATHY
tham and Jayaraman, 1963). The monsoon period (Fig. 39) is characterized by very low salinity values especially at the surface owing to
the large inflow of fresh water and the influx of sea water constitutes
only a distinct bottom layer. During the post-monsoon period the
salinity shows an upward trend with fluctuations and the difference
between the surface and the bottom values tends to diminish. With
this picture of the prevailing salinities, a scrutiny of the tables (VI and
1963
I964
I965
300.
800.
900*C
- 33
.27
0 -
N D J F M A M J J A S O N D J F M A M J J A i b N D
FIG. 39. Temperature, salinity and rainfall data for a typical tropical estuary, the
habitat of Nausitora hedkyi. A, average salinity (surfme, Ernakulm channel);
B, average maximum atmospheric temperature ; C, average minimum atmospheric
temperature; D, average water temperature (surf-), Emctkulem channel.
N. BALAKRISHNAN NAIR AND M. SARASWATHY
tham and Jayaraman, 1963). The monsoon period (Fig. 39) is characterized by very low salinity values especially at the surface owing to
the large inflow of fresh water and the influx of sea water constitutes
only a distinct bottom layer. During the post-monsoon period the
salinity shows an upward trend with fluctuations and the difference
between the surface and the bottom values tends to diminish. With
this picture of the prevailing salinities, a scrutiny of the tables (VI and
1963
I964
I965
300.
800.
900*C
- 33
.27
0 -
N D J F M A M J J A S O N D J F M A M J J A i b N D
FIG. 39. Temperature, salinity and rainfall data for a typical tropical estuary, the
habitat of Nausitora hedkyi. A, average salinity (surfme, Ernakulm channel);
B, average maximum atmospheric temperature ; C, average minimum atmospheric
temperature; D, average water temperature (surf-), Emctkulem channel.