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1

Phytoplankton characterisitcs for different types of Estonian rivers

100%
Piirsoo K., Pall P., Viik M.
Oceanological and Hydrobiological Studies
|
2004
|
issue 1
23-35
EN
The following phytoplankton characteristics and parameters were studied for different ecological types of river reaches: biomass (PB, mg l-1); abundance (PA, 106 cells l-1); number of taxa per quantitative sample (PT); Nygaard's phytoplankton compound quotient (PCQ); phytoplankton dominants (PD). The quantitative characteristics of phytoplankton (species richness, abundance, biomass and PCQ) revealed an increasing trend from small to large upstream catchment areas, but did not respond to different river bedrock or flow velocity. Additionally, PCQ was the highest for the class of 'good' water quality. The phytoplankton dominants were not suitable for typology in the case of small streams where species composition was heterogeneous, without a well-developed phytoplankton community.
2

International and European standards for algal-based monitoring

100%
Kelly M.
Oceanological and Hydrobiological Studies
|
2004
|
issue 1
77-81
EN
International and European standards relevant to algal-based monitoring have been developed by the International Standards Organisation (ISO) and the Comite Europeen de Normalisation (CEN). This work has been given new impetus by the publication of the EU Water Framework Directive (2000/60/EC), which requires the use of CEN and ISO standards where available. Standards addressing diatom sampling and analysis, macrophyte survey, algal survey and phytoplankton analysis are all either published or under development by CEN. There is also a standard under development dealing with quality assurance of ecological assessments in the aquatic environment. Together, these standards should ensure that robust data are collected that can be used for intercalibrations between Member States.
3

Preliminary results from the investigation of benthic diatoms from potential reference river sites in Ireland

100%
Ni_Chathain B., Harrington T. J., McCarthy J., Kelly-Quinn M., Bradley C., Baars J. R.
Oceanological and Hydrobiological Studies
|
2004
|
issue 3
3-15
EN
Benthic diatom samples were collected from 45 potential reference river sites in Ireland. Diatom samples were also collected from 24 lowland eutrophic sites. The main objective for sampling the potential reference sites was to determine the type-specific biological typologies represented by these sites. The lowland sites were sampled as part of another project and are used here for comparative purposes. A larger number of taxa was identified from the reference sites (175 species) in comparison with the lowland sites. (71 species). Distinct differences in diatom distribution and diversity between the reference sites and the lowland sites were revealed by DCA analysis. DCA analysis also showed that the original typological classification of the reference sites was not reflected to any extent in the distribution of benthic diatoms between these sites. However, there was some differentiation between the reference river sites with respect to diatom distribution along axis 1 of the DCA ordination and this was strongly correlated with water conductivity.
4

The transport of material by the rivers of the northern slope of the Pomeranian Lake Land to the Baltic Sea

100%
Szymczak E.
Oceanological Studies
|
2002
|
vol. 31
|
issue 3-4
85-97
EN
The article presents the results of research on the transport of sediment carried by the rivers of the northern slope of the Pomeranian Lake Land to the Baltic Sea in the years 1961-1980. The research includes rivers flowing into the open sea: Rega, Parseta, Wieprza, Slupia, Lupawa and Leba. The total surface of the basins of the rivers in question amounts to 13825.1 km2. The analysis was conducted on the basis of the data concerning the turbidity and flow of the rivers included in hydrological year-books. The size of the transport of the sediment for respective rivers has been counted and the transport of the wash load was analysed with respect to changing conditions of the streamflow and to physical-geographical features of the basin. The transport of the sediment carried to the sea was estimated (46000 tons) and the participation of the rivers of the northern slope of the Pomeranian Lake Land in the total transport of the river wash load from the catchment area of the Baltic Sea has been estimated (0.63%).
5

Experience of using phytoperiphyton monitoring in urban watercourses

100%
Komulaynen S.
Oceanological and Hydrobiological Studies
|
2004
|
issue 1
65-75
EN
The purpose of this paper is to assess how informative phytoperiphyton structural parameters are, and to assess the feasibility of using them for biological monitoring of river quality. The spatial distribution of the attached algae community was studied in some of rivers in Republic of Karelia (NW Russia). The influence of anthropogenic impacts on periphyton communities was analysed in terms of species richness, species diversity, species ecology values, biomass and chlorophyll concentration. All rivers are subjected to different kind of anthropogenic impacts in addition to natural disturbance. With regards to the species composition the differences between the urban and natural stretches of rivers are obvious. The data obtained demonstrate that the phytoperiphyton communities in urban streams are dominated by broadvalent, pollution-tolerant and even saprophilic taxa. Substantial changes in periphyton structure were often caused by an enhanced mechanical impact by storm run-off, which retarded colonisation, rather than any chemical influence. The burial of algae by sand and silt resulted in the loss of species or entire algal assemblages were observed. As result the communities are dominated by a few species with high recolonization potential.
6

Benthic diatoms in polluted river sections of Central Poland

88%
Rakowska B.
Oceanological and Hydrobiological Studies
|
2004
|
issue 1
11-21
EN
Water quality was investigated in the most polluted sections of three rivers in Central Poland: the Rawka, Jeziorka and Bzura. The estimate was carried out using the Lange-Bertalot indicatory method, which is based on various diatom tolerances to pollution, and by calculating the saprobity index of Pantle & Buck. In the investigated rivers, Cocconeis pediculus, C. placentula, Fragilaria construens, F. pinnata, Gomphonema olivaceum, Melosira varians, Meridion circulare, Navicula lanceolata were the most frequent dominants of species sensitive to pollution. The most frequent tolerant species were Achnanthese lanceolata ssp. frequentissima, Cymbella silesiaca, Fragilaria capucina var. vaucheriae, F. ulna, Navicula capitata var. capitata, N. gregaria, N. pupula, and Nitzschia amphibia. The dominants of the resistant group were Gomphonema parvulum, Navicula saprophila, N. veneta, and Nitzschia palea. On the basis of the methods mentioned above, the water of the Rawka River was assigned to water quality class II/II-III, that of the Jeziorka to class II-III/III and that of the Bzura (at both study sites) to class II-III.
7

Monitoring phytoplankton populations and water quality parameters in estuarine rivers of Chesapeake Bay, U.S.A.

88%
Marshall H. G., Burchard L.
Oceanological and Hydrobiological Studies
|
2004
|
issue 1
55-64
EN
A 16-year monitoring program (1986-2002) determined significant long-term trends among phytoplankton populations and water quality parameters in the tidal waters of several rivers (Rappahannock, James, York, Pamunkey) located in Virginia. There were increasing trends in total phytoplankton abundance and biomass, which included the increasing biomass of diatoms, cyanoprokaryotes, cryptomonads, and chlorophytes in each river. There were also trends of increasing downstream salinity, and decreasing concentrations of TN and DIN. The TP and DIP showed none, or variable trends, except in the York River where both concentrations were increasing. General observations also indicated the common occurrence of dinoflagellates and cyanoprokaryotes blooms in several of these rivers.
8

Spatial distribution of chlorococcalean genera in the phytoseston of the we?na and nielba rivers

88%
Messyasz B.
|
|
issue 2
33-44
EN
The chlorococcalean flora from two crossed rivers during the summer period (from July to September 2001 and 2002) was examined. Phytoseston communities were collected from the We?na and Nielba rivers before and behind the cross-rivers as well as from the central place of the cross-rivers. Species belonging to 6 dominant genera: Scenedesmus, Pediastrum, Monoraphidium, Ankistrodesmus, Coelastrum and Tetraedron were found in both rivers. At most of the stations located along the We?na and Nielba rivers after their crossing a trend of increasing green algae species richness together with an increase in the total species number of cells was observed. Furthermore, it was found that the We?na river takes over some of the Nielba phytoseston species.
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