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This study examines the ecology and thermal regime in the Živa voda anchialine cave on Hvar Island (Adriatic Sea, Croatia). The cave, which has no direct connections with the open sea, contains a dense population of the deep-sea hexactinellid sponge Oopsacas minuta Topsent, 1927. Several species of polychaetes, molluscs and crustaceans were also recorded. Two-year temperature data recorded simultaneously at two depths within the cave and at a nearby outside site provide information on thermal conditions in the system. The temperature oscillations within the cave are strongly dampened - varying from 14.6 oC in winter to 17.9 oC in summer - the annual range being four times smaller than in the adjoining sea. These data suggest that O. minuta can withstand higher temperatures than previously expected from deep-sea or cold-water cave occurrences, and that other environmental factors must be playing an important role.

In late summer and early autumn of 1989 benthic mortality in the upper part of Krka estuary extended from the Skradinski buk waterfalls to approximately 5 km downstream. Dead benthic organisms were found on the bottom at depths of up to 4.5 m. During August, a freshwater phytoplankton bloom was recorded in Visovac lake (which supplies the Skradinski buk waterfalls). The green tide in the lake was composed of up to 11.9 million cells. 1--1, predominantly of Synedra acus and Dinobtyon sertularia. At that time the maximal total inflow of phytoplankton cells through the waterfalls was approx. 0.41 S-I (38000 1. d-1). Cells of these two species died after reaching the salt wedge and the cummulative effect of their decomposition apparently caused an oxygen demand sufficient enough to trigger the benthic mortality. Due to the water mass dynamics, the spreading of mortality downstream was slow (from August to October, approx. 5 km). Certain benthic fishes (like Gobius sp.) were observed on the bottom of the affected area in mid-October 1989.

The known geographical distribution of the colonial scleractinian coral Cladocora debilis Milne Edwards & Haime, 1849 has been extended with new record from the eastern Adriatic Sea. This scleractinian coral was found in spring 2002 on the cliff at the south of Lastovo Island (South Adriatic). The new record reported here is the first confirmation of C. debilis presently living in the Adriatic Sea.

Impact of tuna farming on the banks of the coral Cladocora caespitosa in the Adriatic Sea is discussed.

Our recent surveys are focused on four locations where banks occur in the Adriatic Sea: in the Lim channel and near Prvić Island in the northern Adriatic ; near Pag Island in the central Adriatic and in Veliko jezero (National Park “ Mljet” ) in the southern Adriatic. In the area where the banks occur the annual sea temperature range is rather wide ; from 6 °C in winter (the Lim channel) to 29 °C in summer (Mljet Island).

The Greek Government has suggested to UNESCO Educational Sector the initiation of an international environmental education for students and teachers of vocational schools and high-schools entitled SEMEP: South Eastern Mediterranean Sea Environmental Project. This educational Project would like to offer a new pedagogical paradigm of research project based learning, student oriented holistic and interdisciplinary effort, which will address realprblems of local communities and enable outdoor student research activities and problem solving efforts

The protection of nature and the environment plays an exceptionally vital role in coastal zone management since it is more than evident that natural resources and a preserved environment serve as a basis for future development. This work provides a review of the biodiversity, environmental protection and status of a number of environmental factors in the County of Primorje and Gorski Kotar. Regional planning, as a discipline which has traditionally represented the basis for coastal zone management, is experiencing a transformation through the introduction of environmental protection legislation aiming to achieve sustainable development. Based on such principles, the following new documents have been prepared: The Report on the State of the Envirnoment and the Regional plan which include recommendations for further activities in the coastal area and whose realization is a joint assignment and challenge for the 21st century.