Monitoring Program Design - Coastal Lagoons: Ecosystem Processes and Modeling for Sustainable Use and Development - page 308

also a large variety of different uses of lagoon ecosystems which should be considered
for monitoring, such as tourism, fishery and mariculture, coastal technical developments,
land reclamation, coastal defense, sand and gravel extraction, dredging and dumping,
waste discharges, transportation, and other uses specific to the location. Uses within the
drainage area also must be considered, e.g., agriculture (use of fertilizers and pesticides),
industry (emissions to air and water), and settlement (domestic sewage).
Anthropogenic pressure is more evident on coastal lagoons than on open sea
areas. It is generally agreed that the major environmental problems, including
eutrophication, bacterial contamination, toxic compounds contamination, pressure
on living resources and mineral resources, dumping of dredged materials, treated
and untreated sewage discharges, and coastal erosion, are typical for many lagoons.
Other problems, such as invasion of alien species, toxic species, and transport-related
problems, may be specific to certain lagoons.
Developing a monitoring system involves trade-offs. The most obvious one is
between “cost” and “power” of the information gathered. A greater frequency of
observations will decrease the likelihood of erroneous results, all other things being
equal. However, it must be kept in mind that costs of a monitoring program will
increase as well. Consideration of costs is therefore critical during the monitoring
program design phase. Another trade-off is between “power” and “time.” A longer
temporal string of measurements will likely flatten out abnormalities, but time is
always limited for decision making.
Once the goals of the monitoring program are established, a number of “tech-
nical” issues remain to be addressed. These include:

• Spatial frequency of sampling—In a large-scale monitoring program, a
sufficient number of stations must be selected to generate sufficient data
for analysis. Depending on the goals of the program, stations may be
randomly chosen or chosen based on hypotheses or results of preliminary
modeling studies.
• Temporal frequency of sampling—In cases where biotopes are relatively
unchanging, infrequent sampling (once every 5 years, e.g., for deep basin
sediment) is usually adequate. If the ecosystem is very dynamic, more
frequent sampling (at least 4 times per year, e.g., to characterize seasonal
variations) is necessary.

• What is to be sampled—Information relevant to determining environmen-

tal quality of marine resources is manifested in the water column, in
biota, and in sediment. A large-scale monitoring program should include
all three to ensure that biological effects of anthropogenic activities are
covered.

Monitoring programs should be regularly reviewed to ascertain that they have
good quality control and are meeting established goals, basically providing the
information needed for decision making. In addition, it may be wise to update a
monitoring program based on availability of new technology or new information.
Any changes in a monitoring program must take into account the importance of
comparability of temporal data; thus, revisions that would result in breaks in temporal
data should be limited to those that are absolutely necessary.