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An original method for estimating the concentration of chlorophyll pigments, absorption of yellow substance and absorption of suspended matter without pigments and yellow substance in detritus using spectral diffuse attenuation coefficient for downwelling irradiance and irradiance reflectance data has been applied to sea waters of different types in the open ocean (case 1). Using the effective numerical single parameter classification with the water type optical index m as a parameter over the whole range of the open ocean waters, the calculations have been carried out and the light absorption spectra of sea waters tabulated. These spectra are used to optimize the absorption models and thus to estimate the concentrations of the main admixtures in sea water. The value of m can be determined from direct measurements of the downward irradiance attenuation coefficient at 500 nm or calculated from remote sensing data using the regressions given in the article. The sea water composition can then be readily estimated from the tables given for any open ocean area if that one parameter m characterizing the basin is known.
The hydrological conditions, suspended matter concentrations and vertical par- ticulate matter flux were measured as the River Vistula flood wave (maximum discharge) was flowing into the southern part of the Gulf of Gdańsk on 26 May 2010. Extending offshore for several tens of kilometres, the river plume was well stratified, with the upper layer flowing away from the shore and the near-bottom water coastwards.
Part I describes the organizogram and objectives of the International Odra Project (IOP) for the 1997 – 2001. Scientific teams from Germany and Poland took part in the project. The main objective of the IOP program was to describe the status, trend dynamics and metabolic pathways of all types of pollution in the Odra river basin. A scientific task realized by the team from ...... University of Technology (GUT) was to assess the pollution level of organic compounds in water and sediments from the Odra river catchment area. Parts II and III will present the results obtained by the GUT team, which consist of determinations of organic pollutants in water and sediments. The assessment of heavy metals contamination and its mobilisation in water, suspended matter and bottom sediments of the upper and middle Odra river was the main task of the research group from the University of Mining and Metallurgy in Krakow. The obtained results are presented in Parts IV and V.
Fluffy layer suspended matter (FLSM) and surface sediment samples from the Pomeranian Bay were examined for fatty acid, lipid and organic matter contents. FLSM is a several-centimetre-thick layer of fairly concentrated particulate matter lying on the sea floor significantly affecting the flux of matter to depositional basins. Analyses of fatty acids were used to establish sources and decomposition rates of labile organic matter along a transect from the shallow, highly dynamic, Odra estuary to the Arkona Basin, a deep, low energy, depositional area. In FLSM and sediments respectively, the ranges of organic matter contents were 4.0–25.0% and 5.1–23.0%, those of lipids 0.1–5.4% and 0.30–1.67%, and those of fatty acids 50–991 μg g−1 dry wt. and 100–546 μg g−1 dry wt. In shallow waters, the contents of these compounds are very variable, mirroring variations in biological activity and hydrological conditions. The high percentage of polyunsaturated fatty acids in shallow areas indicates the presence of fresh, undegraded, labile organic matter of autochthonous origin. Fatty acids, the most labile components, are transported as suspended matter attached to minerals and finally accumulated in the depositional area in the form of condensed organic macromolecules. The intensity of bacterial decomposition of organic matter in this system is reflected in the high percentage of branched fatty acids. The low fatty acid content in the organic matter is attributed to the high rate of decomposition of the labile organic matter. No linear correlation was found between the contents of fatty acids and lipids.
The extensive investigations of total and mobile heavy metals concentrations in sus­pended matter (SPM) and bottom sediments of the upper and middle Odra river were carried out over the years 1997–2000. Significant levels of contamination were found. Median concentrations for Cd, Pb, Cu, Zn and As in the SPM and sediments were (mg/kg) 7.3 and 8.9, 97.2 and 119, 79.2 and 92.7, 1221 and 1158, and 52.9 and 67.9, respectively. The highest metal pollution of Odra river solids was found with cadmium, zinc, lead and arsenic. The frequency distribution of Cd, Zn, Pb and As in both type of samples, i.e. SPM and sediments, shows high similarity. >From all metals studied, Cd, Zn and As appear to be of particular concern because of the high levels, that appear to be bio­available, and their high mobility. The exchangeable and carbonatic fractions of Cd and Zn reached up to 50% of their total amount. Besides the determination of total metal concentration, the “mobilisation test” of metals in river solids is rec­ommend for monitoring purposes, allowing evaluation of the most mobile, and bioavailable metal fractions. The results of four years of very wide studies of Odra river system suggest that for river monitoring pur­poses, the fre­quency and numbers of samples for chemical analysis of both water and solids - preferably suspended matter - could be reduced to twice a year, with few select sampling sites.
The Maximum Chlorophyll Index (MCI), developed for the MERIS sensor processing scheme, is used to investigate the seasonal dynamics, spatial distribution, and coverage of cyanobacterial blooms over Lake Peipsi (Estonia/Russia) and Lake Võrtsjärv (Estonia). In these optically complex waters, the amounts of suspended matter and dissolved organic matter vary greatly and independently of the phytoplankton biomass. We demonstrate that MCI is a useful, new tool for detecting and estimating cyanobacterial biomass (R2 = 0.73), phytoplankton biomass (R2 =0.70) and chlorophyll a concentration (R2 = 0.64). The MCI-derived results are consistent with known patterns of phytoplankton dynamics in these lakes, whose optical properties are in the same range as in many coastal regions of the Baltic Sea.
This overview presents in detail the state of knowledge of the abilities of various components of the Baltic Sea environment to accumulate trace elements and radionuclides. Particular components of the Baltic ecosystem (abiotic and biotic) are considered as potential monitors of pollutants. The use of seaweeds, e.g. Fucus vesiculosus or Zostera marina is recommended, also molluscs, e.g. Mytilus edulis, for biomonitoring surveys of metal pollutants and radionuclides in the Baltic Sea. However, several requirements need to be met if results are to be reliable. Since metal levels and radionuclide activities in the growing tips of F. vesiculosus reflect exclusively the levels of their dissolved species in the ambient seawater, this alga is very useful for monitoring dissolved species of metal pollutants and radioisotopes in the Baltic ecosystem. In contrast, M. edulis, a filter feeder is an appropriate tool for monitoring trace elements occurring in both chemical forms, i.e. dissolved and suspended species. Therefore, full information on the bioavailability and toxicity of heavy metals (depending on their chemical speciation) as pollutants of the Baltic Sea can be obtained if at least two biomonitoring organisms are applied simultaneously, e.g. F. vesiculosus and M. edulis. Moreover, the data matrix can be interpreted more accurately if not only trace element but also macroelement concentrations (Ca, Mg, Na, K) in these two representatives of Baltic phytoand zoobenthos are taken into consideration; this point requires special attention. Two coastal species of fish, i.e. Zoarces viviparus and Perca fluviatilis, are good biomonitors of metallic contaminants, so their use as sentinels is recommended. The budgets of chemical elements and the ecological status of the Baltic Sea are presented. Several ‘blacksp ots’, e.g. large estuaries and seaport towns, heavily polluted by trace elements, are identified in the Baltic Sea and other enclosed seas such the Mediterranean and the BlackS eas. Of these seas, the Baltic is the most heavily loaded with trace elements and organic pollutants. The overview identifies gaps in our environmental knowledge of the Baltic Sea, and sets out possible priorities, key areas or strategies for future research.
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