Part Of Adriatic Sea Research Articles

Wind influence on sailing ship navigation across Croatian part of Adriatic Sea

The paper is about characteristics analysis of major winds across the Croatian part of the Adriatic Sea and their impact on organization of sailing ship navigation from prehistory until mid nineteenth century. Research area was divided into northern, middle and southern part of eastern Adriatic, and parameters for three prevailing winds – bora, jugo and mistral, were observed over four climatological seasons and also over annual average values on 18 main meteorological and climatological weather monitoring stations. Information generated from such data was intertwined with archaeological findings from the eastern Adriatic coast and historical writings that witness sailing across the area. Historical writings that were used consist of itineraries and some of the earliest nautical pilots written as a navigational aid for the area of the eastern Adriatic. The prime goal was to determine if there is a correlation between reconstructed sailing routes that existed in times when information about landscape and surrounding occurrences and processes (wind in this case) was collected by observation and contemporary measured data. It was also important to determine if navigation was affected by advances in nautical technology, particularly ship hull and sail construction, and navigation equipment.

Geochemical characteristics and genesis of Mačje Jame and Vranjski Potok As-Cu-bearing iron occurrences west and southwest of the town of Busovača, Mid-Bosnian Schist Mountains

Investigated landslide is the largest active mass movement along the Croatian coast, situated on the north-eastern slope in the central part of the Rjecina Valley (north-eastern coastal part of Adriatic Sea, Croatia). Slopes in this valley are formed in siliciclastic rocks - flysch, while limestone rock mass is visible on the cliffs around the top of the river valley. The slopes are at the limit of a stable equilibrium state, and mass movement phenomena have been recorded since 19th century. Samples for laboratory testing were taken from the flysch bedrock, weathered zone and slope formations, and were recovered to provide specimens for data on their mineralogical, physical and geotechnical properties. Correlation between mineralogical and geotechnical properties and their influence on sliding processes are presented in this paper. Clay fraction in samples ranges from 17 % to 38 %. Clay activity of the tested samples is from 0.45 to 0.89, and the residual friction angle varies from 13.0° to 17.7°. These results correspond to the presence of kaolinite and illite groups of clay mineral. Mineral composition and decrease in strength of fine-grained soil materials, due to the increase of pore water pressures, contributes to the slope movements.

Distribution of phytoplankton community in Kotor Bay (south-eastern Adriatic Sea)

Abstract The goal of this paper was to explain variability of phytoplankton in a shallow coastal area in relation to physico-chemical parameters. Temporal variability and composition of phytoplankton were investigated in the Kotor Bay, a small bay located in the south-eastern part of the Adriatic Sea. Samplings were performed weekly from February 2008 to January 2009 at one station in the inner part of the Kotor Bay, at five depths (0 m, 2 m, 5 m, 10 m, 15 m). Phosphates, nitrites and nitrates ranged from values under the level of detection to the maximum values of 1.54, 1.53 and 23.91 µmol l−1, respectively. The phytoplankton biomass — represented by chlorophyll a concentration — ranged from 0.12 to 6.78 mg m−3, reaching a maximum in summer. Diatoms were present throughout the whole sampling period, reaching the highest abundance in March (3.42×105 cells l−1at surface). The peak of dinoflagellates in July (2.2×106 cells l−1 at surface) was due to a single species, Prorocentrum micans. The toxic dinoflagellate Dinophysis fortii occurred at a concentration of 2140 cells l−1 in May. The present results of phytoplankton assemblages and distribution provide valuable information for this part of the south-eastern Adriatic Sea where data is currently absent.

A complex landslide in the Rječina Valley: results of monitoring 1998-2010

Results of landslide monitoring undertaken between 1998–2010 on the north-eastern slope of the central part of Rjecina Valley in front of Grohovo village (north-eastern coastal part of Adriatic Sea, Croatia) are presented. This is the largest regional active landslide. The slopes around the Rjecina riverbed are formed in siliciclastic sedimentary rocks with flysch characteristics. The bedrock is mostly covered with unstable slope formations. A limestone rock mass is visible on the cliffs around the top of the river valley. The landslide is complex and retrogressive, with 13 sliding bodies. It occurred in December 1996 by displacement of an initial landslide body where movement had been registered in the 19th century. The limestone mega-blocks and separated rocky towers on the top of the slope have also moved, which is an atypical phenomenon of the flysch slopes in the area of Rijeka. After initial sliding ceased, and major movements subsided, monitoring of benchmark movements from 1998 until 2010 determined further maximum displacements on the upper part of the slope, and minimum movement in the lower part. The area of the Rjecina Valley from the Valici Dam to the Pasac Bridge was selected as a pilot area in the framework of the Croatian-Japanese bilateral joint research project. Monitoring results provided the basis of establishing an early warning system for possible landslide occurrence and estimating the degree of landslide risk.