Content of the Volume 28.
Tóthmérész, B.: DivOrd 1.60. Diversity Ordering: Finite and infinite samples
Virágh, K. (1994): Spatial aspects of vegetation dynamics induced by herbicide disturbances in a Hungarian loess grassland community. - Tiscia 28, 3-13.
Abstract. Major floristic changes induced by leaf-herbicides selective to dicots and monocots and a comprehensive leaf-herbicide in an old perennial grassland community were studied for 10 years using permanent quadrates at 3 spatial microscales (at 400 cm², 1 m² and 5 m² plot sizes). Great impact of spatial scale upon the detection of dynamic phenomena and recognition of recovery tendency as well as the assessment of its degree was analyzed during the local secondary microsuccessions following herbicide- disturbances. Similarity analyses and principal coordinates ordinations were applied to measure the rate of floristic change and to reveal trends in temporal variation of species composition, variability of regenerative trajectories, as well as to estimate the degree of recovery at 400 cm², 1 m² and 5 m² plot sizes. The results indicated significant differences in the variation of floristic composition and in the rate of major floristic changes at small versus larger sizes of quadrates. It was concluded that the different changes in spatial microheterogeneity of the originally homogeneous stand of the community caused by the herbicide-disturbances strongly affected the appropriate plot size for detecting grassland recovery-dynamics. The spatial heterogeneity changes induced by the herbicides were especially critical in comparison of the different treatments as well as in assessing the degree of recovery of the treated plots to control ones. It was stated that the observable differences between floristic pattern at different spatial scales would be the result of different degrees of spatial heterogeneity within the community. A change of spatial scale (the size of experimental plots) brought forth, in fact, a new perception of vegetation dynamic processes and the results also highlighted different aspects of species abundance hierarchy.
Keywords: herbicide-disturbances, spatial scales, temporal floristic
pattern
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Bagi, I. (l994): Measures of association and correlation between two coexistent forms of Carex serotina Mérat; pattern and distribution of dominance.-Tiscia 28, 15-19.
Abstract. Two Carex serotina forms ('A' similar to forma serotina, 'B' similar to forma thalassica) occur together on the mud of a meander lake in the Tiszaalpár Basin. The distribution of the forms in space seems to be independent of the location of the cenological sample in the lake bed. The frequencies of dominances show a close paralelism in the 2 - 10 % domain of dominances. The measures of association and correlation between the two forms refer to a close positive relation of the forms.
According to our current information, it is the first paper in which such a degree of phenotypical variability increase is reported, which had led to the discontinous segregation between two cooccurrent plant forms in a natural population.
Key words: Carex serotina, mud vegetation, plant architecture, vegetation
structure
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Brankovic, D. and Budakov, Lj. (1994): Phytoplankton community and saprobiological characteristics of Lake Ludas during the Spring season. - Tiscia 28, 21-24.
Abstract. This paper deals with the results on examinations of phytoplankton community and saprobiological characteristics of the Lake Ludas, during the period from March to May (the spring), in the year of 1992. A hundred and eighteen species, varieties and forms of Cyanophyta, Pyrrophyta, Xantophyta, Bacillariophyta, Euglenophyta and Chlorophyta were recorded. All the examined samples were dominated by Chlorophyta. Bacillariophyta ranked the second place, while Xantophyta were present only in one of the samples with only one species. The density of phytoplankton community was changeable and varied from 0.85x103 to 115.73x103. Saprobity index, after Pantle and Buck, varied from 2.2 to 2.6, pointing out to β-, β-α-, and α-mesosaprobity.
Key words: bioindicators, density of algae, phytoplankton,
saprobity.
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Vuckovic, M., Stojanovic, S., Stankovic, Z., Zderic, M., Kilibarda, P., Radak, Lj. and Radulovic, S. (1994): Quantitative presence of macrophytes in basic channel network of Hydrosystem Danube - Tisza - Danube. - Tiscia 28, 25-28.
Abstract. Quantitative presence of aquatic vascular plants is given at certain sections of Hydrosystem Danube - Tisza - Danube in Backa: channels Vrbas - Bezdan, Backi Petrovac - Karavukovo and Jegricka. Among submerged plants which are not rooted, species Ceratophyllum demersum is the most frequent in all sections. From submerged plants that are rooted, Myriophyllum spicatum and Vallisneria spiralis have the greatest quantitative presence. Floating non rooted hydrophytes are small floating flowering plants and water ferns. Spirodela polyrrhiza, Lemna gibba, Salvinia natans and Azolla caroliniana have high coverage values at certain spots. From group of floating rooted hydrophytes, most numerous are Trapa natans, Nymphaea alba, Nuphar luteum and Nymphoides flava. Due to great surface and big floating leaves, they are covering large areas of water mirror, especially in channel Vrbas - Bezdan. Among numerous emerged macrophytes giving coast zone of all channels, highest participation is of Phragmites communis, Typha angustifolia and Glyceria maxima. It is concluded that differences in floristic structure and quantitative presence of various life forms of aquatic plants in investigated sections of Hydrosystem Danube - Tisza - Danube are due to different age of channels (30 to 200 years), different physico-chemical conditions of aquatic environment, purpose functions of channels, pollution degree and application of different protection measures.
Keywords: Hydrosystem Danube - Tisza - Danube, hydrophyta,
floristic structure, ecological groups, quantitative presence.
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Nosek, J.N. and Bereczky, M.Cs. (7994): The effect of some environmental factors on Protozoa populations of the River Danube. - Tiscia 28, 29-36.
Abstract. The simultaneous effect of nine environmental factors (water discharge, water temperature, dissolved oxygen content, ammonium content, pH, chemical oxygen demand (by KMnO4), total dissolved solids, Coliform and psychrophyl bacterial counts) were investigated on the population size of 30 planktonic Protozoa species. Data series of four years with different hydrological regimes were evaluated by correlation and path analyses. Regarding the direct effects higher than 5%, 57% of the species were influneced by ammonium content, 40% by pH, 33% by dissolved oxygen content, by chemical oxygen demand and by total dissolved solids each, 27% by Coliform, 23% by psychrophylic bacterial count, 17% by water discharge and 7% by water temperature.
Key words: planktonic Protozoa populations, running water,
path-analysis, environmental factors, River Danube.
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Djukic, N., Maletin, S., Pujin, V., Ivanc, A., Kojcic, K., and Miljanovic, B.(1994): Ecological estimation of water quality of the Tisa by physico-chemical and biological parameters. - Tiscia 28, 37-40.
Abstract. Investigations during the period 1990-1992 showed disturbance of oxygen regime with evident minimum in the summer to occur in the Tisa river concurrently with a relatively high content of nutrients, mineral nitrogen particularly. Zoocenological analysis also pointed to increase in organic load. In plankton samples and bottom fauna and fish, the species being characteristic of eutrophic environment dominated. Therefore, a section of the Tisa river investigated is characterized by a rapid process of eutrophication.
Keywords: oxygen regime, nutrients, zooplankton, bottom fauna, fish,
eutrophication.
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Maletin, S., Djukic, N., Stojanovic, S., Ivanc, A., Zderic, M., Matic, A., Andric, B., Radak, Lj. and Miljanovic, B. (1994): Meliorative effect of grass carp (Ctenopharyngodon idella) in controlling aquatic macrophytes in the Tisza valley. - Tiscia 28, 41-45.
Abstract. Effect of biomanipulation with grass carp monoculture was studied to suppress macrophytes overgrowth under controlled conditions during vegetation period of 1993. The experiment was performed in two separate basins of 0.15 ha each. A hundred specimens of 3-5 years of age and approximately 4 kg individual body weight on the average were stocked in each basin. A favourable meliorative effect coinciding with a significant increase in ichthyomass and satisfactory condition and general physiological status of fish was obtained when abundance and coverage of aquatic (Polygonum amphibium and Spirodela polyrrhyza) and semiaquatic vegetation (Phragmites australis, Typha latifolia and T. angustifolia) varied and supplementary feeding with fresh biomass of Ceratophyllum demersum (95%) and Potamogeton pusillus (5%) was regularly supplied. Also, selection in nourishment taking into consideration the presence of stands of various phytocenoses was evident.
Keywords: herbivorous fish, aquatic weeds, biomanipulation, food selection.
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Budakov, Lj., Brankovic, D. and Gajin, S. (1994): Comparative investigation between phytoplankton and the intestinal contents of carp. - Tiscia 28, 47-51.
Abstract. Algological and ichthyological examinations were performed during the period from September 1990 to May 1993 in the Old Begej (Stari Begej) nature reserve. Main aim of this paper is to recognize the phytoplankton in the water and in the intestinal content of carp. Age of the examined carp individuals was between 2+ and 6+. Average body length waried bbetwen 144.30 and 3887.55 mm, and body weight between 1203.50 and 1691.56 g. All available food promoted good growth of carp. 232 species, varieties and forms of algae were recorded in the samples from Old Begej, and Chlorophyta was a dominant group of algae. In the intestinal content of carps 160 taxa of algae were recorded but dominant groups were Bacillariophyta and Chlorophyta. On the basis of saprobity index after Pantle and Buck and quantity of carp, the water of Old Begej can be ranked as b-mesosaprobic one.
Keywords: bioindicators, carp, intestinal content, phytoplankton, saprobity.
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Ivanc, A., Maletin, S., Djukic, N. and Miljanovic B. (1994): Ecophysiological interpretation of haematology of different Percidae species in the river Tisza. - Tiscia 28, 53-56.
Abstract. Haematological analyses of pikeperch (Stizostedion lucioperca) and perch (Perca fluviatilis) originated from the river Tisza nearby Novi Becej were performed. The fish were caught by electrofishing, recovered during 24 hours, and finally heart puncturing was undertaken for blood collection. Number of erythrocytes, erythroblast percentage, haematocrit, haemoglobin concentration, mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH), mean corpuscular haemoglobin concentration (MCHC), number of leucocytes, and differential blood count were determined. Different values for haematological parameters were obtained, in particular haemoglobin concentration, MCHC, and differential blood count. The differences noticed were discussed from the aspect of idioecological specificity of these two Percidae species.
Keywords: erythrocytes, erythroblast, haematocrit, haemoglobin, MCV,
MCH, MCHC, leucocytes.
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Karabasil D. and Bukurov, D. (1994): A contribution to the study of the cause and distribution of Minamata disease in the lower course of the River Tisza (YU). -Tiscia 28, 57-62.
Abstract. The research was started after a mysterious disease had been observed with a ten- year-old girl in Novi Sad, Yugoslavia. It was manifested by convulsions lasting for several hours. These crises of consciousness repeated cyclically in irregular intervals of approx. 90 days. Diagnosis of the disease was Sindroma-Lenox-Gastaut. Test on toxic metals shoved enormously increased mercury contents in the little patient's urine. Our further investigations brought us to the irrigation/drainage canal DTD (Danube- Tisza-Danube) a pond called Beljanska Bara and the river basin of the river Tisza. Fish from Beljanska Bara had a considerable quantity of accumulated mercury. The child was poisoned postnatally in the phase of lactation through her mother, who had used the fish mentioned above regularly in her meals. The goal of the paper is to prove that Sinrdoma Lenox-Gastaut is in fact postnatal poisoning with methyl-mercury in the phase of lactation.
Keywords: Phenyl-mercuric acetate, methylation, methyl-mercury, lactation,
methyl- mercury poisoning, Sindroma Lenox Gastaut, DMPS.
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Tóthmérész. B. (1994): DivOrd 1.60. Diversity Ordering: Finite and Infinite Samples. - Tiscia 28, 63-65.
Abstract. Changes in the 1.60 release of DivOrd program are discussed. The main improvement is that it is possible now, to choose between the finite and infinite sample versions of rarefaction diversities. The arrangement of the menu system also has changed a little.
Keywords: diversity index families, diversity ordering, rarefaction
diversity
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Erdei, Zs., Tóthmérész, B. and Erdei, A. (1994): Linear algorithm to calculate indirect spatial statistics for completely random multi-species communities. - Tiscia 28, 67-72.
Abstract. We present a linear algorithm to calculate the diversity of species combinations (or "species list - number of plots" diversity) for completely random communities in an indirect spatial series analysis. It serves as a null model to compare completely random multispecies patterns to real ones which are observed on the field. An efficient algorithm to derive explicitly all the possible species combinations and their frequencies is also proposed. Turbo Pascal algorithms to IBM-compatible PC's and results about the running time of the algorithms are also presented.
Keywords: spatial statistics, indirect spatial series analysis, null
model.
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