MAP Technical Reports Series No. 106 UNEP

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Once the phenomenon to be monitored or studied has been identified, it is of the
uppermost importance to plan a monitoring programme, that both in terms of frequency in time
and distribution and typology of sampling in space will be representative of the phenomenology
under study as well as of the sequential mechanisms and the triggering effects: in other words
it is necessary to establish a redundant programme that will allow for grasping the most relevant
events happening during the process. From the correct interpretation of the phenomena and the
implications in terms of environmental and hygienic-sanitary impact, may descend the
correctness of the interventions.
Among the general objectives that should characterise the control and management
programmes for the coastal zones, the following items should be considered:
- Control of the environmental conditions and the qualitative status of the water
body:
- climatic variations (Stravisi, 1991; Cacciamani et al., 1992);
- definition of the trophic state;
- presence of algal blooms;
- presence of dystrophic conditions (anoxia of bottom waters);
- pollution levels;
- presence of toxic micro-algae;
- quality standards for recreational activities.
- Time evolution of phenomena under control using long time series (see Penna,
1990; Aertebjerg, 1991; Beukema, 1991; Braun, 1991; Cescon, 1989; Dooley,
1991; Eleftheriou, 1991; Heip, 1991; Herman, 1991; Kendal, 1991; Skojldal, 1991):
- trends of parameters indicating the trophic levels (nutrients, chlorophyll, etc.);
- trends of traditional pollutants (heavy metals, pesticides, radio nuclides, etc.);
- changes in the typical phitoplanctonic species (Hickel, 1991);
- dynamics of the fauna (particularly in terms of bentonic ecosystem) and flora
(Hutchinson, 1991, Neiland, 1991);
- assessment of rehabilitation plans and validation of the effectiveness;
- applied scientific research.
Therefore, the quality management of coastal waters should be derived from an
integrated monitoring programme and process modelling which will include:
- "point" and "distributed" nutrient sources;
- transport of nutrients;
- hydrodynamics of the coastal waters;
- a description of the ecological and physiological processes triggered by the
excessive nutrient loading and the consequent environmental degradation
phenomena.
10.5 Mathematical models
In addition to the monitoring programmes and the establishment of geo-related data
bases, the use of models is essential on the one hand for the coherence analysis of the available
data and the understanding of phenomena, and on the other hand for the planning and the
evaluation of the effectiveness of the management policies such as:
- point source control by means of sewage treatment and disposal;
- distributed source control by means of soil conservation techniques and fertiliser
restrictions;