Salinity Intrusion and Seasonal Water Quality Variations in the Tidal ...

Source: Keller (1984)
....
There is another 230,000,000 km 3 of water which is chemically bound to
materials on the earth's mantle.(Schippers, 1991)
Table 1.2. The population and water requirement in the study area
2001 2006 2011 2021
Population,(lakhs) 16.11 I 16.76 17.35 18.52
Water 441 478 516 595
requirement(MLD)
Source: Kerala Sasthra Sahithya Parishad Project Report,2002
The hydrosphere functions as the flywheel ofthe global heat engine by cushioning
out sharp thermal fluctuations. The fraction offresh water actually available to terrestrial
biota is precariously meager. The remarkable dissolving capacity ofwater makes all the
aquatic ecosystems vulnerable to deleterious pollution. According to Schippers (1991),
425xl0 12 M 3 of water vapor enters the atmosphere per year of which 320xl0 12 M 3
precipitates on sea and 105xl0 12 M 3 precipitates on land out of which 75xl0 12 M 3
evaporates and 30xl0 12 M 3 flows back to the sea sooner or later. Hence whatever little
fresh water is available gets denatured by human interventions in the form of his
economic activities. Water is the medium common to all ecosystems and maintains the
integrity ofall the organisms that live, grow and reproduce in it. Hence, water is a crucial
element of all ecosystems and its availability has governed the siting of all communities,
hence the development and progress ofman. Water is indispensable because:
4