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Three hydrographic cruises were conducted during 1997-1999 in north Aegean Sea, in order to study the dissolved oxygen (DO) and nutrient distributions in Strymonikos Gulf impacted by the riverine waters of the Strymon River. The approaches used in this paper include a preliminary estimation of the nutrient load of Strymon River and the influence of the riverine waters upon the DO and nutrient distribution in Strymonikos Gulf. Nutrient levels recorded in Strymon River were similar with other international Rivers. The influence of Strymonas River on the DO and nutrient distributions was clearly detected during December 1997 and May 1998. On the contrary, during March 1999 the influence of Strymon River was not so clearly detected. High nutrient concentrations were recorded close to the mouth of the river. As mixing with offshore waters progressed, nutrient levels declined dramatically. Plots of atomic DIN:P (ratio of the total dissolved inorganic nitrogen to dissolved inorganic phosphorus), Si:P (ratio of dissolved silica to dissolved inorganic phosphorus) and Si:DIN ratios in Strymonikos Gulf, during the three sampling periods studied, indicated stoichiometric P-limitation in about 34%. Furthermore, the data indicated significant probable N-limitation (31.4%), while Si-limitation was not probable (2.9%). In particular, 31% of the data showed a defined P-limitation in December, whereas 30% of the data showed N-limitation. It is noteworthy that Si-limitation was not recorded. In May, the atomic DIN:P ratio indicated P-limitation in about 21% and N-limitation in about 46%. Si-limitation was not recorded. Finally, in March, the 51% of the data showed P-limitation, whereas only the 16% showed N-limitation and 8% showed Si-limitation.

The present study is performed with the aim to reduce the levels of polluting emissions from fuel combustion that produce acid rains and the greenhouse effect (NOx, CO2). The electric field effects on the processes of heat/mass transfer and propane combustion are studied in order to perform electric control of the levels of polluting emissions from the flame. The results of experimental studies show the direct influence of the electric field's enhanced mass transfer on local variations of the flame composition and fuel combustion. The related variations of the flame temperature, processes of soot formation, carbon capture and deposition along the flame channel flow are studied by varying the field strength and the equivalence ratio of the propane-air mixture. The results show that the electric field effect on soot for- mation, carbon capture and sequestration, for fuel-rich flame flow, can be used to reduce the levels of CO2 emissions from the flame. In addition, the field-enhanced heat/ mass transfer to the channel walls, for fuel-lean conditions, can be used to control the fuel combustion, flame temperature and temperature- sensitive levels of NOx emissions. The most pronounced electric field effects on fuel combustion and composition of the products are observed in the limit of the weak fields (U<1,2 kV, E<105 V m-1).

Uncontrolled disposal of urban and industrial wastewaters into the sea led to the fact that in mid eighties
the Kasštela Bay, near the city of Split, Republic of Croatia, became one of the largest and most widely
known pollution “hot-spot” areas of the Mediterranean region. The pollution of the Bay caused “red
tide” and mass mortality of marine organisms. Numerous conflicts arose, and the quality of life was
reduced due to the changed quality of the sea. Local communities recognized the problem, and the longterm
solution of wastewater management has been developed. This solution envisages the collection of
all domestic wastewaters at two points in the area, and, after treatment at an appropriate level, their discharge
via long submarine outfalls into a less sensitive marine environment. For the implementation of
the first phase of the long-term solution, a project “Eco Kaštela Bay” has been launched. The project is
financed from local and governmental sources, as well as loans of the World Bank and the European
Bank for Reconstruction and Development. The present paper describes the area, environmental conditions,
and the approach applied in the long-term solution of waste waters management.

The Peninsula of Sithonia is one of many typical regions in Greece in which overexploitation of local
aquifers has led to several serious problems related to quantity and quality degradation of groundwater
reserves. In this paper, a management plan is presented that aims at the utilization of the so far
unexploited surface water resources of the area in order to restore the degraded aquifers and to supplement
the groundwater supplies, mostly for domestic use. To this end the total municipal water
demand and the potential of surface waters are first estimated at both the local and regional levels.
Next, four alternative management schemes are examined, each one consisting of a different number
of reservoirs. A preliminary evaluation of these water supply alternatives, that concludes the paper, is
based on both operational and economic factors in order to facilitate a future multi-criterion decisionmaking
analysis.