In 1980,1982 and 1984-1987 the total count of bacteria (TC), the number of saprophytic bacteria (plate count, PC), total Coliforms and Enterococci were determined at 22 to 30 sampling sites in the pelagial of Lake Peipsi-Pihkva.
Bacterioplankton production was investigated seasonally at two locations from May to November 1985-1987.
Eleven inflows and the outflowing River Narva were studied three times in the vegetation period 1985-1987 and in winter 1987.
The average TC was highest in L. Pihkva (4.3 x 106 cells ml-1), lower in L. Lämmijärv (3.9 x 106 cells ml-1) and the lowest in the northern part of L. Peipsi (2.2 x 106 cells ml-1).
According to these data, L.
Pihkva and L. Lämmijärv were similar to typical Estonian eutrophic lakes.
L. Peipsi had mesotrophic features with a tendency to eutrophy in its southern part.
The numbers of saprophytic bacteria (PC) in L. Pihkva and L. Lämmijärv fluctuated from 110 to 360 cells ml-1, in L. Peipsi from 98 to 290 cells ml-1, and up to 5400 and 5900 cells ml-1 in the mouths of the Rivers Velikaja and Suur Emajogi, respectively.
The average production value per vegetation period was 37.9 g C m-2.
The numbers of Coliforms and Enterococci indicated that the pelagial was in a good sanitary state.
Enterococci and high total Coliform numbers (up to 1000 per 100 ml) were determined at the mouths of the Rivers Suur Emajogi and Velikaja.
In comparison with the early 1960s, 1.5-2. (...)
Mots-clés Pascal : Bactérie, Coliforme, Saprophyte, Enterococcus, Streptococcaceae, Micrococcales, Milieu eau douce, Lac, Contamination biologique, Dénombrement, Dynamique population, Productivité biologique, Variation saisonnière, Pollution eau, Eutrophisation, Estonie, Europe Est, Europe, Bactérioplancton
Mots-clés Pascal anglais : Bacteria, Coliforms, Saprophyte, Enterococcus, Streptococcaceae, Micrococcales, Freshwater environment, Lakes, Biological contamination, Enumeration(counting), Population dynamics, Biological productivity, Seasonal variation, Water pollution, Eutrophication, Estonia, Eastern Europe, Europe, Bacterioplankton
Notice produite par :
Inist-CNRS - Institut de l'Information Scientifique et Technique
Cote : 97-0152329
Code Inist : 002A14D05E. Création : 21/05/1997.