Environmental Engineering Reference
In-Depth Information
Table 1.10
Major components of oceanic water
Component
Table 1.11
Minor components of oceanic water
Component
Concentration (mg/kg of sea water at
35
Concentration
(
‰
salinity)
g/kg of sea
water at 35
psu salinity)
μ
Calcium
412
Magnesium
1,294
Aluminium
2
Nitrogen
15
Argon
4
Potassium
399
Arsenic
3
Silicon
2.9
Barium
20
Sodium
10,760
Iron
2
Strontium
7.9
Iodide
60
Bicarbonate
145
Lithium
180
Boron
4.6
Molybdenum
10
Bromide
67
Phosphorus
60
Chloride
19,350
Rubidium
120
Fluoride
1.3
Titanium
1
Sulphate
2,712
Uranium
3
Source
Pytkowicz and Kester (
1971
)
Vanadium
2
Zinc
3
descending and warming up, these desert zones
have very little rainfall and high evaporation. The
Red Sea located in the desert region but almost
completely closed shows the highest salinity of all
(40 psu), but the Mediterranean Sea follows as a
close second (38 psu), and lowest salinity is found
in the upper reaches of the Baltic Sea (0.5 %). The
Dead Sea is 24 % saline, containing mainly
magnesium chloride (MgCl
2
). Shallow coastal
areas are 2.6
Cadmium, chromium, caesium,
copper, krypton, manganese, neon,
nickel, antimony
2.4*
Bismuth, cobalt, gallium, germanium,
mercury, niobium, lead, selenium, tin,
thallium, xenon, zirconium
0.4*
Silver, gold, beryllium, cerium,
helium, hafnium, lanthanum,
tantalum, thorium, tungsten, yttrium,
radium
0.05*
Dysprosium, erbium, europium,
gadolinium, holmium, lutetium,
praseodymium, samarium, terbium,
thulium, ytterbium
0.005*
3%.
The components of sea water at the surface,
coastal waters and estuarine waters often suffer
characteristic seasonal changes due to factors
such as evaporation, precipitation and run-off. In
the north-western Bay of Bengal, the pre-mon-
soon period (summer) is usually characterized
with high saline surface water and relatively high
pH. The picture in monsoon period is totally
opposite. Due to increased precipitation and run-
off from the adjacent land masses, the salinity of
the surface water lowered along with pH, but the
concentrations of the nutrients increase, which
may be attributed to increased run-off from the
adjacent agricultural
3.0 % saline and estuaries 0
-
-
Indium, protactinium, scandium 0.0007*
*Concentrations are sum totals for all elements
Source
Holland (
1978
)
and volume of wastewater discharged in major
estuaries of India.
A case study highlighting the seasonal varia-
tions of hydrological parameters in the Hooghly
estuary (a continuation of Ganga
Bhagirathi
River system) is depicted in Tables
1.14
and
1.15
.
A comparison between Tables
1.14
and
1.15
exhibits signi
-
elds, municipality, urban
sectors, etc. (Mitra
2000b
). The composition of
coastal waters also gets affected by wastewater
discharges from industrial and anthropogenic
factors. Table
1.13
lists the population around
cant tidal variations in relation to
the hydrological parameters and therefore sug-
gests the consideration of tidal effects while
monitoring the water quality of an estuary.
