Signatures of pigments and processes in the south Adriatic Pit - project MEDUZA

During two cruises of the MEDUZA experiment conducted in July 2003 and May 2005 various data were obtained over the deepest part of the southern Adriatic Pit. Temperature, salinity, light transmission and fluorescence were measured in July 2003. During May 2005, except CTD measurements the samples were taken for laboratory determination of phytoplankton pigments with HPLC technique. During both cruises irradiance and radiance were measured at 14 wavelengths in the range 340-715 nm with optical probe to about 100 m depth. Bad weather conditions during both cruises caused interruption of measurements that continued after 24 to 48 hours. Stormy conditions have resulted in a slightly different structure of the water column. In the periods of measurements recorded were diurnal rhythms in a series of parameters, caused by solar radiation cycles in the surface layers as well as fluctuations in the deeper layers under the influence of the internal tide. Meteorological conditions and changes in sea level are also described. The analysis included the principal component and correlation analysis between the measured and derived parameters in order to establish a link between the in-situ pigments and multispectral data. During both cruises diurnal vertical oscillations were observed in biotic and abiotic parameters. Chlorophyll pigments prevailed over other pigments preventing other pigments to be distinguished spectrally. Regression models for chlorophyll a were established from radiance and reflectance ratios.Original Abstract: Tijekom nekoliko krstarenja u okviru Meduza eksperimenta obavljenih u srpnju 2003 i svibnju 2005 (http://jadran.izor.hr/meduza/meduza_g.htm), pribavljeni su raznovrsni podaci iznad najdubljeg dijela juznog Jadrana. Temperatura, salinitet, propusnost za svjetlost i fluorescencija mjereni su u srpnju 2003. Tijekom svibnja 2005., osim CTD mjerenja uzeti su uzorci za laboratorysko odredivanje pigmenata fitoplanktona. Tijekom oba krstarenja mjereno je zracenje na 14 valnih duljina u rasponu 340-715nm optickom sondom do oko 100m dubine. Losi vremenski uvjeti tijekom oba krstarenja uzrokovali su prekid mjerenja koja se nastavljaju nakon 24 odnosno 48 sati. Olujni uvjeti rezultirali su nesto drugacijom strukturom vodenog stupca. U razdobljima mjerenja zabiljezeni su dnevni ritmovi u nizu parametara, uzrokovani ciklusima sunceva zracenja u povrsinskim slojevima kao i oscilacije u dubljim slojevima zbog unutarnje plime. Meteoroloski uvjeti i promjene r