Coastal Marine Environment Sustainability - Sustainable Practices in Geoenvironmental Engineering - page 265

8
Coastal M arine Environment Sustainability
8.1 Introduction
For many different reasons, the coastal marine environment can be considered to be an
important part of the geoenvironment. It is the recipient of (a) liquid discharges from sur-
face runoffs, rivers, and groundwater and (b) waste discharges from land-based industry,
municipal, and other anthropogenic sources. It is also a vital element in the geoenviron-
ment that provides the base for life-support systems. The combination of these two large
factors, with their direct link to human population, makes it (the coastal marine environ-
ment) an integral part of the considerations on the sustainability of the geoenvironment
and its natural resources.
8.2 Coastal Marine Environment and Impacts
The coastal marine environment is a signiicant resource. A healthy coastal marine ecosys-
tem ensures that aquatic plants and animals are healthy and that these do not pose risks
to human health when they form part of the food chain. In this chapter, we will discuss
(a) the threats to the health of the coastal sediments resulting from discharge of contami-
nants and other hazardous substances from anthropogenic activities, (b) the impacts
already observed, and (c) the necessary remediation techniques developed to restore the
health of the coastal sediments.
8.2.1 Geosphere and Hydrosphere Coastal Marine Environment
The discussion in Section 1.2 in Chapter 1 on the inclusion of many elements of the hydro-
sphere in the geoenvironment points out that the coastal marine environment is included
in the discussions on the receiving waters of the geoenvironment. This is because it is
impacted by the outcome of anthropogenic activities. The sea provides the habitat for
many living organisms and is an important ecosystem in the geoenvironment. Seawater is
one of the major supply sources for our water resources through evaporation of the seawa-
ter and subsequent deposition on land as rainfall. Evapotranspiration constitutes the other
major source of water for rainfall. Circulation and recycling of water on land is a very
important process for preservation of the global environment and life support for of all
living organisms. This is not only because no living organisms can survive without water,
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