Coastal ecosystem consists of estuaries
and coastal waters and lands located at the lower end of drainage basins, where stream and river systems meet the sea and
are mixed by tides. The coastal ecosystem includes saline, mixed saline and fresh water and fresh waters, as well as coastlines
and the adjacent continental shelf lands. Coastal wetlands are commonly called lagoons, salt marshes or tidelands. Our
coasts provide important fish and wildlife habitat, far beyond their limited geographic extent. Coastal ecosystems comprise
more than 40 percent of the world population. Natural habitats face serious threats in coastal regions from human population
growth and the development and disturbance that are often a consequence of growth. Population projections indicate that our
coastlines will continue to receive the majority of the worlds growth and development,
promising to compound today's habitat losses.
The ecosystem of coastal
regions has rich biodiversity due to the presence of the estuaries, mangroves and coral reefs. The sea level changes- global
warming, changes in coastal region, geomorphology, mining activities and natural hazards like
floods, tsunami and earth quake adds to the magnitude of the coastal problem.
Keeping all these factors in mind, this conference has been conserved.
Coastal India
has a long coast line of about 7560 km with east and west coasts. The monsoon dependent part of our country in most
of the years depends on the ground water supply to full fill the people and societies
water requirements. The situation becomes more critical in monsoon failure periods. However, the rising demand for fresh ground
water, mostly for drinking, irrigation and industrial use lead to problems in
coastal area force us for over exploitation of these resources. But the ground
waters are increasingly become saline or polluted due to this anthropogenic stresses. There is a need for sustainable exploitation
to yield fresh water if the flow mechanisms are well established to protect, conserve and restore the coastal aquifer. So
the ground waters of coastal aquifer
is to be described, evaluated and explained primarily by application of principles of hydrogeochemistry to understand the
migration of solutes using field data, isotopes and the numerical models. The salinity is not only due to seawater intrusion
but also due to soil salainisation, palaeosalinity and secondary salt precipitation pollution etc. Human pressure on
the coast zone from urbanization, industrialization, aquaculture and agricultural activities is responsible for this situation.
The potential for an
aquifer to be contaminated from near-surface sources is indicated by the presence of young waters. Apparent ages and the percentage
of young water in the samples provided additional information on aquifer susceptibility. For samples that are indicative of
binary mixtures of young and old waters, methods like 3H can
be used to estimate the apparent age of the young fraction, as a means of evaluating the validity of the other hydro geological
study. Due to increasing anthropogenic stress the occurrence of selected chemical constituents in the water samples will be
controlling the aquifer susceptibility, apparent ground-water ages and percentages of young water. Hence a comprehensive idea
on various methods adopted to understand the behavior of costal ground water and their sustainability is required to establish
the behavior of the coastal aquatic system by developing a proper methodologies.
Coastal areas can be
exploited for the biological yield due to the natural or induced mixing with the sea
water, but also due to the presence of old marine water in the lagoons, lakes and aquifers and the generation of saline waters
and brines in flat areas at an elevation close to the current sea level. The situation becomes more complex when there is
a presence of backwaters, estuaries, saltpans, wetlands and wide tidal ranges. Tsunamis –cyclones which occur on a random
basis and are independent of all other effects causing the elevated water levels to invade the continental regions. This natural
phenomenon extends into the land along the distributaries channel of the rivers affecting the surface and subsurface waters.
This conference will help to have proper management strategy and to decipher the sources responsible for the vulnerability.
