Biological research reports from the University of Jyväskylä 1

Distribution of aquatic Oligochaeta in the Finnish Lake District

SUMMARY. The distribution of oligochaetes was examined at sampling stations grouped into three types: (1), in eutrophic and dystrophic areas or in areas polluted by pulp-mill wastewaters; (2), slightly eutrophic stations; (3), ‘clean’ stations unaffected by sewage or other inputs. Limnodrilus hoffmeisteri and Potamothrix hammoniensis were practically the only species in group 1, and the same species accounted for two thirds of the total numbers in group 2, although Peloscolex ferox and some other species also occurred. At the cleanest stations the dominating species were P. ferox, Psammoryctides barbatus, Stylodrilus heringianus and Tubifex tubifex. A factor analysis showed that L. hoffmeis…

Meiofauna of the profundal zone of the northern part of Lake Ladoga as an indicator of pollution

Benthic meiofauna was sampled at 19 stations, mainly in the northern part of Lake Ladoga, from depths between 13 and 199 m and from types of environment ranging from sheltered areas near pollution sources to less polluted open areas. About 80 taxa were identified, of these 70 to the species level. The greatest numbers of species were oligochaetes (24 species) and harpacticoids (8 species). Certain quantitative ratios of meiofauna were shown to be correlated with environmental data. The species of the oligochaete families Lumbriculidae and Aeolosomatidae and the harpacticoids as a collective group, excluding Canthocamptus staphylinus, were most clearly confined to the less eutrophied environ…

Organic chlorine compounds in lake sediments. II Organically bound chlorine

Abstract Organically bound chlorine together with inorganic chloride was measured from dated bottom sediment layers of 18 lakes in Central Finland and compared to organic matter contents. Pulp mills were found to be the source of significant increase of the accumulation of all of these materials in the 20th century.

Mercury and chlorinated hydrocarbons in zoobenthos of Lake Päijänne, Finland

The average amounts of mercury, PCBs, and sigma DDT (primarily DDE), found in macrozoobenthos, on the wet basis, in Lake Päijänne, Finland, for the time period 1972-1974, were 79 ng/g, 29 ng/g, and 8 ng/g, respectively. Lindane was found in negligible amounts in only 2% of the samples examined; aldrin was present in 10% of the samples; no dieldrin was detected. Mercury and PCB concentrations varied regionally in the lake. PCB and sigma DDT concentrations were greater in the predatory bottom animals than in the herbivores or detritus feeders, and the amounts of chlorinated hydrocarbons were greater in profundal animals than in littoral animals. No significant correlation was apparent between…

Mercury and chlorinated hydrocarbons in the food chain of Lake Paijanne, Finland

The sediments and various organisms in Lake Paijanne were examined for contaminants. The average mercury content of water plants was 9, of plankton 14, of sediment 114, of zoobenthic predators 83, of fish 332–1510 and of birds 240–13685 μg kg−1 (wet weight). The average PCB content of plants was 3, of plankton 21, of the zoobenthos 44, of fish 36-117 and of birds 219–13490 μg kg−1. The average ΔDDT content of plants was 0.5, of plankton 6, of the zoobenthos 14, of fish 7–42 and of birds 144-8262 μg kg−1. Regional differences in mercury content were most pronounced in sediment and fish. PCB concentration was highest near a town. ΔDDT was quite evenly distributed. Water plant species did not …

Chlorinated hydrocarbons and mercury in aquatic vascular plants of lake Päijänne, Finland

Meiofauna ratios as environmental indicators in the profundal depths of large lakes.

Two sets of samples from Lake Paijanne and one from Lake Ladoga were used to examine the relations between the meiofauna and environmental variables. The most obvious indicators of an unpolluted environment were, in order of importance, the true meiofauna/total meiofauna ratio, the proportion of Aeolosomatidae, the proportion of Harpacticoida (excluding C. staphylinus), the meiofauna/macrofauna biomass ratio, the proportion of Naididae and the A. crassa + P. schmeili/true meiofauna ratio. Conversely, the clearest indicators of a polluted environment were the proportion of resting stages of Cyclopinae, the Nematoda/non-resting Copepoda ratio, and the proportions of Tubificidae, Oligochaeta, …

Meiobenthic naidid and aeolosomatid oligochaetes from the profundal zone, and relations of species to eutrophication

Oligochaetes were sampled using meiobenthos methods from depths of between 20 and 94 m in Lake Paijanne in 1986. Individuals belonging to several species of the Naididae and Aeolosomatidae, which are generally considered to include mainly littoral or lotic species, were found more or less regularly at these profundal depths. The naidid species Chaetogaster langi and Arnphichaeta leydigii were more abundant in the deepest areas than at 20 m. Species also appeared to react differently to water quality. The naidid species Chaetogaster langi and the aeolosomatid species Aeolosoma quaternarium, A. hernprichi and Rheomorpha neiswestnovae were most abundant on average at oligotrophic, unpolluted s…

Mercury in sediments of lake Päijänne, Finland

Organic chlorine compounds in lake sediments. III. Chlorohydrocarbons, free and chemically bound chlorophenols

Abstract Chlorohydrocarbons and free and chemically bound chlorophenols, catechols and guaiacols were measured from lake sediments in Central Finland. Chlorohydrocarbons occurred at low backround levels except chlorocymenes from pulp mills and PCBs near the city of Aanekoski, where a local leakage occurrs. Free chlorophenols (hexane extractables) were found in all 18 areas studied, but the bound ones (extracted with strong alkali) only in the pulp mill reciepient lakes where they dominated. Preliminary analyses of chemically bound chlorophenols in high molecular fractions of spent bleach liquors and pulp mill effluents indicated that majority of chlorocatechols and guaiacols are bound alrea…

Lacustrine profundal meiobenthos as an environmental indicator

Organic loading and eutrophy is indicated at profundal depths by large numbers of resting copepodid stages of cyclopoid copepods, by the occurrence of the naidid oligochaete species, Amphichaeta leydigii and Specariajosinae, and the harpacticoid species Canthocamptus staphylinus, and by a low meiobenthos/ macrobenthos biomass ratio. An oligotrophic environment is indicated by the occurrence of the aeolo-somatid oligochaetes Aeolosoma quaternarium, A. hemprichi and Rheomorpha neiswestnovae, the naidid oligochaete Chaetogaster langi and the harpacticoid species Attheyella crassa and a high meiobenthos/ macrobenthos biomass ratio.

Chernobyl-derived radiocaesium in fish as dependent on water quality and lake morphometry

137Cs concentrations in perch Perca fluviatilis, pike Esox lucius and roach Rutilus rutilus obtained from lakes of different size and water quality in an area which received about 10–67 kBq m−2137Cs, were compared with environmental data. Radiocaesium concentrations were highest in pike, and were about two to three times higher in the pike and perch than in the roach. The largest perch had about four times more 137Cs than the smallest ones, but the activities in the pike and roach were independent of fish size. All of the water quality parameters examined correlated with 137Cs concentrations in the fish, but the concentrations of 137Cs in the bottom sediment did not. l37Cs fallout and water…

On the ecology of littoral Oligochaeta of an oligotrophic Finnish lake

In material sampled from 0.5–6 m on two sampling dates and three subareas the dominant Oligochaeta were Limnodrilus hoffmeisteri Claparede and Peloscolex ferox (Eisen), both composing more than 30% of the abundances of oligochaetes present. The numbers of Oligochaeta were mostly higher in August than in May. Regional differences could be found although the lake seems to be very homogenous. Temporal and vertical variations were detectable in separate subareas. The oligochaete biomass was maximal at 2 m depth. In soft bottom sediments the oligochaetes composed 15.9% of macrobenthos biomass and 12.2% of numbers, but on the stony bottom only 1.9% of numbers. The ratio of Oligochaeta/Chironomida…

Organic chlorine compounds in lake sediments. IV. Dioxins, furans and related chloroaromatic compounds

Abstract Polychlorodibenzo-p-dioxins (PCDDs), polychlorodibenzofurans (PCDFs), polychloronaphthalenes (PCNs) and coplanar PCBs were measured in surface sediments from 18 lake areas in Central Finland. Toxic 2, 3, 7, 8-substituted PCDD and PCDF congeners occurred at low levels (

The occurrence of oligochaetes in lake chains receiving pulp mill waste and their relation to eutrophication on the trophic scale

Earlier conceptions of oligochaetes as indicators of trophy were somewhat enlarged to include more littoral, meiofaunal and naidid species. The amplitudes of different species on the oligotrophy-eutrophy axis seem to be generally large. Certain species which probably originally occur mainly in very humic environments seem also to be able to endure very strong organic loading caused by pulp mills. Species of this kind seem to be Dero digitata, Specaria josinae, Slavina appendiculata and Aulodrilus pluriseta. Chaetogaster langi and Arcteonais lomondi are also species which live in areas receiving pulp mill wastes. A. lomondi and D. digitata seem to be species living in greater depths than the…

Effects of eutrophication and organic loading on the occurrence of profundal harpacticoids in a lake in southern Finland.

Harpacticoids made up 19 and 30% of the meiobenthos proper by number and 39 and 55% by biomass at maximum depths and a depth of 20 m, respectively, in Lake Paijanne. Harpacticoids accounted for higher proportions of the total meiobenthos in oligotrophic and unpolluted areas than in polluted areas. Seven species were identified, with Canthocamptus staphylinus confined to semi-lotic areas influenced by organic pollution from a pulp mill. Other species exhibited somewhat different distributions in oligotrophic and mesotrophic areas. Harpacticoid densities were most closely correlated with oxygen content and phytoplankton biomass, and correlations with environmental values were closer at maximu…

Lacustrine, profundal meiobenthic oligochaetes as indicators of trophy and organic loading

Meiobenthic and macrobenthic oligochaetes were collected from two depths in Lake Pajanne and examined together with environmental data in which two environmental gradients can be seen. Numbers of Piguetiella blanci, Aeolosoma quaternarium and Aeolosoma hemprichi were positively correlated with oxygen saturation and negatively correlated with total phosphorus and COD suggesting that these species are indicators of oligotrophic conditions. Numbers of Amphichaeta leydigii, Specaria josinae and Vejdovskyella comata were positively correlated with total phosphorus which implies that these species prefer eutrophic conditions. The last three species and Dero digitata showed positive correlations w…

Diversity of meiofauna in the lacustrine profundal zone: Bathymetric differences and influence of environmental factors

The diversity and species richness of total meiofauna, Harpacticoida and Oligochaeta in relation to depth and other environmental variables were studied at nine stations and in two profundal depth zones in Lake Paijanne which includes both oligotrophic and eutrophicated or organically loaded areas.

POPs and organic polysufides in sediments of Lake Ladoga

Abstract The study included one station close to a pollution source (depth 59 m) and another far from polluted areas (depth 40 m). Samples were analysed for organic chlorine, bromine and sulfur compounds. Samples taken with a corer were sliced to the layers of 0–1, 1–4, 4–7 cm etc. down to the depth of 34 cm. The dating was made with two independent methods, the 210Po method and with the soot particle counting method. The analyses were made with a multiresidue method. Gas chromatography was connected to low resolution mass spectrometry (LRMS) or to high resolution mass spectrometry (HRMS). A different extraction was applied to screen the possible occurrence of polysulfides. Typical chloroph…