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easily identifiable by some laboratories. In general, lagoons have a large number of
taxa, relatively high diversity, and a relatively high abundance of biomass. There is
likewise a large amount of periphyton, which hampers analysis. In general, biological
sampling in lagoons requires more time than required for the open sea and also requires
a greater degree of knowledge about the ecosystem.
7.2.5
M
ONITORING
OF
I
MPACT
OF
D
IFFERENT
U
SES
OF
L
AGOONS
Coastal lagoons are characterized by intensive exploitation; therefore, they are
subjected to various physical, biological, and social interactions (
as explained in
Chapter 8).
In some lagoons, the presence of such activities may require the
monitoring of additional parameters. These activities include tourism, sewage
discharges, fisheries, mariculture, transport/shipping,
coastal defense, dredging
and dumping of dredged material, sand and gravel extraction, and other coastal
engineering activities.
•
Settlements and tourism—Human population tends to concentrate in
coastal areas, particularly around lagoons. In addition, seasonal tourism
may bring a growth in population amounting to a multiple of the perma-
nent population as happens in Venice Lagoon (Italy) and in Mar Menor
Lagoon (Spain). In many cases, this growth is beyond the carrying capac-
ity of the environment as well as the capacity of local infrastructure.
Consequently, such activity may create serious environmental damage,
particularly since not many countries are able or willing to efficiently
regulate tourism activities. Tourism tends to gravitate toward nature and
landscape conservation areas as well as toward precious and pristine spots,
consequently destroying the tourist amenities.
Environmental monitoring in such cases is related to the pressure of tourism and
estimating the carrying capacity of the environment and the negative effects of
tourism. Tourism and recreational activity usually destroy or make unintended
changes in habitats, have effects on species diversity and rare species, cause changes
in quality of bathing waters, etc. Modeling can be applied to demonstrate different
scenarios of pressure effects of tourism on the lagoon ecosystem.
• Sewage discharges—The relationship between sewage discharges and
microbiological pollution and the effects on sanitary conditions are evi-
dent. Species of pathogenic bacteria are found in the vicinity of sewage
outflows. Monitoring is often undertaken to determine bathing water qual-
ity, utilizing established techniques based on concentrations of coliform
bacteria. Distribution of microbiological pollution along the coast is often
a subject of modeling activity.
• Fisheries—Lagoons are usually very productive and are often intensively
exploited as fishery sites. They also are highly sensitive to overexploita-
tion. The pelagic system as well as the bottom system may be adversely
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