bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ein Computer‐Programm zur quantitativen Bestimmung der Keimzahl mittels der Most‐Probable‐Number (MPN)‐Methode
Authors: Nagel M. , Blüml T. , Stelzer W. , Schulze E. 
Published: February 2007

AbstractThere are explained the statistical fundamentals of the estimation of the number of bacteria by means of the most‐probable‐number method (MPN method) inclusive of the confidence intervals and the probability of the sample results. On this basis, a program in Turbo‐Pascal is prepared for the operating systems C/PM or MS‐DOS for the computation of both single MPN estimations and complete tables inclusive of probability and confidence limits, their listing being appended.
The Structure of the Zooplankton Community and the Dynamics of its Biomass in the Lake Jaisamand (Rajasthan: India)
Authors: Rao P. S. , Durve V. S. 
Published: February 2007

AbstractZooplankton of the lake Jaisamand was represented by 50 taxa out of which 22 were Rotifera, 18 Cladocera, 5 Protozoa, 3 Copepoda and 2 Ostracoda. The total zooplankton exhibited a bimodal pattern with the first peak occurring in December and the second of a little less magnitude in June. The perennial zooplankters were Keratella valga, Brachionus falcatus from Rotifera, Ceriodaphnia spec. from Cladocera and Mesocyclops and Heterocyclops spp. from Copepoda. Considering surface zooplankton as a whole, Rotifera dominated the planktonic biomass followed by Copepoda, Cladocera, Ostracoda, Protozoa and Insecta. The species composition of the mid‐stratum zooplankton was not much different from that of the surface. Interestingly, there was a presence of Cladocera in the anoxic bottom waters. The low and occasional presence of Calanoid copepods, the abundance of Cyclopoids and Cladocerans point to the eutrophication in the lake.
Nährstoffbelastung und Trophie von Talsperren der DDR. Teil 2: Charakterisierung der trophischen Verhältnisse durch einen Trophieindex
Authors: Loth P. , Ackermann G. 
Published: February 2007

AbstractOn the basis of the measurements in 54 storage reservoirs from 1980 till 1985, the Trophic State Index (TSI) by Walker is tested with respect to its functional relations in terms of the criteria of chlorophyll, o‐phosphate and limit of visibility and applied to storage reservoirs. For this, the statistical relations between the chlorophyll concentration and the reciprocal limit of visibility (a vertical extinction coefficient for the non‐planktogenic share being taken into account) as well as the o‐PO4‐P content during the full overturn in spring are determined and transferred into the index of trophy. The total index is formed as the arithmetic mean of the three indices on the basis of chlorophyll, limit of visibility and o‐PO4‐P. The index of trophy provides a safe description of the trophic state of storage reservoirs, especially the expansion of the mesotrophic and hypertrophic range as against the eutrophic and polytrophic range contributing to the increased sensitivity of the classification.
Size Fractions of Heavy Metals in Waters
Authors: Vymazal J. 
Published: February 2007

AbstractThe heavy metal content of river water samples with 12 and 15 mg/l dry matter of seston is increased to 400 … 3900μg/l by the addition of inorganic heavy metal salts, and after three days the distribution of the heavy metals is determined by fractional filtration (8, 3, 1.2, 0.8, 0.65, 0.45 and 0.22 μm pore size). More than 80% of Ni, Co and Mn are found in the fraction <0.22 μm, 60% of Pb and Cu in >8 μm as well as 40 and 25%, resp., in <0.22 μm, Cd, Cr and Zn are found in all fractions, 60 … 80% being in the fraction <0.22 μm, 90% of Fe occurring in the fraction >8 μm. The influence of specific parameters of water quality as pH‐value and seston concentration on the distribution requires further investigations.
Control of Ion Balance in Water by Determining the Cation Content
Authors: Gomółka E. , Gomółka B. 
Published: February 2007

AbstractPresented is an analytical method which enables a quick determination of the total cation content in water. In this method, total alkalinity is determined before passage, and mineral acidity after passage through the ion exchange bed. The sum of the two parameter values gives the total cation content in the water. Verification was carried out with model solution and natural water samples. The method makes it possible to verify the ion balance of the electrolytes, as well as to determine the salinity level (i.e. the concentration of dissolved substances) in the sample.
Phyto‐ and Zooplankton Composition and Some Ecological Observations on a Man‐made Lake in Wadi el Majanin, Libya
Authors: Khan M. A. , Zarmouh M. M. 
Published: February 2007

AbstractThe small eutrophic man‐made lake in Wadi el Majanin, Libya has a well‐buffered hydrogen‐carbonate (98 … 160 mg/l CaCO3) system (pH = 7 … 7.8) and a poor Secchi visibility (21 … 35 cm). Conductivity data (272 … 480 μS/cm) fit the water‐body in class 2 (‘freshwater’ range) of Beadle. The annual surface water temperature cycle (before noon readings) showed strong seasonal variations from 12 °C in Jan. and Feb. 1986 to 28.5 °C in June, 1987. The lake sustains a good crop of plankton populations. The main phytoplankton were species of Pediastrum, Scenedesmus, Navicula, Amphora, Synedra, Gomphonema, Oscillatoria, Gomphosphaeria and from zooplankton these were Keratella, Polyarthra, Brachionus, Moina, Acanthocyclops and nauplii of copepods. The presence of euglenoids supports the enriched water status of the ecosystem. Planktonic algal flora appeared closer to the eutrophic chlorococcales‐diatom type (Hutchinson). Rotifers dominated the zooplankton community. A well established macrophytic vegetation was lacking.
Oberflächenaktivität und bakterizide Wirksamkeit quaternärer Aminooligomere
Authors: Prodanov E. P. , Dimov A. D. 
Published: February 2007

AbstractWe synthesized series of polyfunctional aminooligomers by means of condensation from polychlorparaffine with ethylenediamine. After modifying them with dimethylsulphate watersoluble oligomers of (quaternary) polyamines are obtained, which can be successfully used as biocides for treating circulating cooling‐waters from different refinery plants. The products have low foaming and formed foam is unsteady. The bactericide properties of the successful samples are good. For the interval time for two to twenty hours of treatment at static conditions the microbe number value decreases by more than 99.99% at a 50 mg/dm3 dose of a biological active substance. At dosing it up to seventy‐two hours the biomass is finely dispersed and does not precipitate on the walls of the chemical set‐equipment.
Dynamik des Phytoplanktons der Oberwarnow 1984–1986
Authors: Hübener Th. , Kell V. , Kolbow D. , Strehlow B. , Lenschow U. 
Published: February 2007

AbstractThe development of the phytoplankton was observed from 1984 to 1986 in the Warnow‐River (GDR, Mecklenburg). The dominant algae throughout the year were the Bacillariophyceae with their maximum in spring (1984: 36.1 mm3/1, 1986: 32.3 mm3/1) or in autumn (1985: 48.3 mm3/1). There is not any limitation of phytoplankton by inorganic nutritation (N, P) throughout the year. The phytoplankton production was most influenced by the turbulance of water. Classification of banked‐up rivers with the help of the plankton‐quotients of Thunmark and Nygaard is impossible.
Ein einfaches Modell zur Simulation der Schwermetallmigration im Boden
Authors: Pelzer J. , Böhmer B.‐M. , Meier U. 
Published: February 2007

AbstractThe heavy‐metal ions are bonded in the soil in different ways. With increasing concentration in the soil the soluble share of heavy‐metal ions which is transported by the percolation water into lower soil layers and finally into the ground‐water grows. The decrease of the distribution quotients and sorption capacities in the lead > cadmium series can be explained by the form of bonding at the soils which is specific to heavy metals. The elements are fixed as monohydroxo complexes. The heavy‐metal retention capacity decreases with increasing time of introduction. For the estimation of the migration of heavy metals in agriculturally used soils it is recommended to combine accumulation models with migration models.
Eliminierung von Schwermetallen aus komplexbildnerhaltigen Abwässern durch Kalk‐/Kreide‐Fällung
Authors: Schilling H. , Fischwasser K. 
Published: February 2007

AbstractA report is given on laboratory investigations into model waters containing Cu2+‐, Ni2+‐ or Zn2+‐ions and tartrate, citrate, NTA or EDTA as complexing agents. There were determined residual concentrations of the metal ions at different shares of complexing agents, which are achieved by the precipitation with lime and chalk. Chalk is added in order to secure the required exess of calcium ions without causing an overalkalinization of the water. In the range of pH = 8…9, however, residual concentrations lower than 1 mg/1 are achieved only for copper ions in the presence of tartrate.
Stabilization System for Waste Water Treatment and Use. Part 2. Biology
Authors: Svoboda M. , Koubek P. 
Published: February 2007

AbstractFrom the hydrobiological viewpoint the stabilization system represents three different ecosystems with specific biocoenoses. Through natural processes the processed nutrients pass through the anaerobic and semi‐aerobic stages to be utilized in the trophic chain in a fishpond. Here, the process of waste water treatment is brought to the state of beta‐mesosaprobity with variation towards alpha‐mesosaprobity. The annual yield of fishes amounted to 1,060 kg/ha on the average. The economic returnability of the system is 20 years. A critical analysis of the performance of the system allowed the proposal of its optimization. It would consist in the complete separation of the entirely different biocoenoses in three consecutive basins preceding the stabilization pond. When the pond is fished out, the second and the third basin would accumulate the effluent of the first basin until the end of March. In this way the nutrients in incoming waste water would be utilized purposively by the algae during the vegetative period, the algae by the filtering zooplankton and the latter by the fish.
New Approach on Kinetics of Mercury Removal by Sulfide Regenerated Weak Base Anion Exchange Resin
Authors: Nenov V. , Kamensky D. , Dobrevsky I. 
Published: February 2007

AbstractThe kinetics of mercury removal by a conventional type weak base anion exchange resin, regenerated by sodium sulfide solution was studied. Assuming that the active centers of sulfide regenerated resin are located on the surface of macropores, a mathematical model which explains the extremely high specificity of this resin towards mercury was developed.
Organic Matter Mineralization in the Littoral and open Lake Sediments of the Shallow Neusiedlersee, Österreich
Authors: Mühlhauser H. A. 
Published: February 2007

AbstractNeusiedlersee is a very shallow lake located in the eastern part of Austria. It is characterized by a reed belt that covers nearly 70% of its perimeter. Extended mixing and sediment resuspension due to wind action is observed in the open lake. Autochthonous seston and organic matter accumulates at the fringe and inside the reed belt. Space‐time fluctuations of bacterial populations in the open lake and littoral sediments and mineralization of organic matter in the littoral sediments were studied. Total number of bacteria was determined by epifluorescence. Ammonifying bacteria were determined by an MPN method. Experiments to evaluate organic matter mineralization were performed. Potential proteolysis and sulfate reduction were evaluated. Evidence of organic matter aggregation affecting the patchiness of bacterial populations in the sediments was found. Bacterial populations in the littoral sediments were more numerous and more active than those in the open‐lake sediments. Results suggest that the microbial community in Neusiedlersee littoral sediments play a key role in the carbon and energy flow for the whole lake.
Seasonal Succession of Phytoplankton in a River of Western Ghat, India
Authors: Rao Jayaprakash , Madhyastha M. N. 
Published: February 2007

AbstractThe monthly variation in the phytoplankton was investigated for a period of 2 years at Netravathi river of the Western Ghat region. The number of individual species of phytoplankton were enumerated on the basis of the cell count with an inverted microscope. The diatoms were dominant during winter (November, December) and the blue‐green algae were dominant during summer (March, April). Myxophyceae, Dinophyceae and Xanthophyceae were sparsely represented. A relationship between different environmental parameters, heavy metals and planktonic communities was established. Some of these environmental factors show significant correlations, whereas some others correlated not at all.
Nickel Nitrate Induced Changes in Visceral Hexokinase Activity of Three Freshwater Teleosts
Authors: Jagadeesh K. B. , Shaffi S. A. 
Published: February 2007

AbstractThe effect of lethal and sublethal concentrations of nickel nitrate on the visceral hexokinase activity in Labeo rohita (Ham.), Clarias batrachus (Linn.), and Channa punctatus (Bloch) was investigated. A maximum fall in hexokinase activity was recorded in liver followed by muscle, kidney, brain and gill at lethal and sublethal levels of nickel nitrate. Among these three fishes the variations observed in Labeo rohita are greater than in Clarias batrachus and Channa punctatus. The fall in hexokinase activity was minimum at a sublethal level and maximum at a lethal level in all the tissues of these three fish species. The fall in hexokinase activity was highest at 18 h exposure in comparison to 12 h or 8 h in these fishes. However, the differential fall in the visceral hexokinase activity may be ascribed to compartmentation of tissues, precipitation of toxicant and respiratory distress.
Toxicity and Accumulation of Lead with Respect to Algae and Cyanobacteria: A Review
Authors: Vymazal J. 
Published: February 2007

AbstractLead is a relatively minor element of the earth's crust but widely distributed in low concentrations in uncontaminated sedimentary rocks and soils. The average content of lead on soil is about 10 mg/kg; the background levels of lead in freshwaters and freshwater sediments are estimated to be below 3 μg/l and 40 μg/g, respectively. Lead is commonly found in water plant tissues but its essentiality has never been proved. The present paper is aimed at summarizing literature data concerning occurrence of lead in water environments and its toxicity and bioaccumulation with respect to algae and cyanobacteria. The data concerning mode of toxic action of lead, factors affecting toxicity and accumulation, concentration factors of lead in algae and cyanobacteria and lead content in various algal and cyanobacterian species are given.
The Interference of Tripton on CO2 Dark Fixation in a Temperate Inpoundment with High Input of Suspended Solids
Authors: Mühlhauser H. A. , Montecino S. V. 
Published: February 2007

AbstractDark 14CO2 fixation in primary productivity measurements had been studied extensively. Dark fixation is partly biological, partly non‐biological. Despite several attempts to give an explanation, its variability remains a problem. The bulk research on this matter was done on the biological factors of dark fixation, but abiotic arguments were little considered. The abiotic fraction of 14CO2 fixation, associated with large suspended solids inputs to the temperate impoundment Rapel (Chile), was studied. Seston samples collected from the euphotic zone were analyzed for organic‐inorganic fractions, total‐N and total‐P. Determinations of NO3‐N, PO4‐P, dissolved total‐N and dissolved total‐P, and chlorophyll a were related to seston samples. Primary productivity was measured by the 14C method in the euphotic zone. Results suggest that in reservoirs with large tripton contents a competition for plant nutrients including C (as HCO3−) exists between tripton and phytoplankton. Dark fixation experiments, during large inputs of suspended solids, showed significant amounts of 14C adsorbed to the tripton. Thus, insufficient acid stripping of adsorbed 14C in the experiments hampers the correct assessment of 4CO2 dark fixation.
The Phytoplankton of the Straw Board Mill Effluent Mixing Zone in Comparison with a Reference Zone and Diluted Zones of the River Dhasan, M. P. India
Authors: Sen U. S. , Bais V. S. , Yatheesh S. 
Published: February 2007

AbstractThis paper embodies findings of twelve month on the effect of straw‐board mill effluents on the distribution and diversity of phytoplankton of the river Dhasan. The phytoplankton of the three stretches (Reference Station A, Effluent Mixing Station B and Diluted Station C) of the river was sampled regularly every month and analysed qualitatively and quantitatively. Simultaneously some of the relevant chemical parameters of the water were also analysed. The result of the water were also analysed. The result of the plankton study showed that the plankton concentration was very low. It ranged from 166 organisms to 2240 organisms per litre only. The maximum and minimum numbers were recorded in February and June‐July respectively at all stations. Winter was found to be the most favourable season and the rainy season the most unfavourable with regard to the population density. From the samples collected from all the stations we could recognise 54 genera of chlorophyceae, 25 genera of Bacillariophyceae, 24 genera of cyanophyceae, 3 genera of Dinophyceae and 2 genera each of euglenophyceae, chrysophyceae and xanthophyceae. The percentage composition of the various groups varied with stations, but by and large chlorophyceae and bacillariophyceae dominated in all the sampling stations. The data were subjected to ‘ANOVA’ and ‘t’ tests. The results show that the observed variations in the distribution and diversity of phytoplankton among the three stations were not significant at the 5= level except in the case of Euglenophyceae.
Umwelthygienisehe Aspekte der Freisetzung gentechnisch modifizierter Mikroorganismen
Authors: Böttcher I. 
Published: February 2007

AbstractThe water‐hygienic aspects of the possibility of a release of microorganisms modified by genetic engineering are discussed on the basis of three examples: release of large amounts of bacterial spores into a drinking water protection zone for insect control etc., biotechnological nitrate elimination under anaerobic conditions in the drinking water treatment, protection of groundwater resources when the sewage‐engineering deep‐shaft biology is applied. In future, the biotechnology with microorganisms modified by genetic engineering (GEMs) will be increasingly applied in industry (pharmacy, foodstuff production), agriculture (pest control, plant preservation) and environmental protection (drinking water treatment, wastewater treatment, disposal site systems). Therefore, the monitoring of air, wastewater and production with respect to their content of GEMs or recombined DNA is a component of production hygiene in the sense of an environmental monitoring.
Toxicity of Mercury to Mudskipper, Boleophthalmus dentatus (cuv. and VAL.). Part 2: Changes in the Activity of Acid and Alkaline Phosphatases in Gills
Authors: Lakshmi R. , Kundu R. , Mansuri A. P. 
Published: February 2007

AbstractActivities of the acid and alkaline phosphatase changes in gills of mudskipper B. dentatus have been analysed during treatment with different concentrations of mercuric chloride for different durations. The study shows a more or less linear inhibition of the activity of acid and alkaline phosphatases with increasing mercuric chloride concentrations as well as duration of treatment.
Major Ions in the Damietta Branch of the River Nile, Egypt
Authors: Saad M. A. H. , Abdel‐Moati A. R. 
Published: February 2007

AbstractMajor cations and anions were investigated in the Damietta branch of the River Nile. The branch is divided into two different regions; the fresh Nile water (Region A) and the mostly marine environment (Region B). The latter region represents the Damietta estuary. The relative abundance of the major ions in the fresh water system was Na > Ca > Mg > K, HCO3 > Cl > SO4 > CO3, while in the mostly marine area it was Na > Mg > K > Ca, Cl > HCO3 > SO4 > CO3. Regional and monthly variations of the major ions were related to the duration of the Nile discharge and climatic conditions. The major ions ‐to‐ chloride ratios for Region A were higher than those in the adjacent Mediterranean waters, while those for the mostly marine region were slightly lower.
Histopathological Lesions in Heteropneustes fossilis Subjected to Acute Thiodan Toxicity
Authors: Narain A. S. , Singh B. B. 
Published: February 2007

AbstractThe common Indian freshwater catfish, Heteropneustes fossilis, was exposed to the 96 h‐LC50 (0.007‐0.013 ppm) of the organochloride thiodan (endosulfan) for 4 days. The stressed fishes showed various histopathological changes. In the liver, extensive degeneration of cytoplasm, pycnosis of nuclei, and loss of glycogen was observed most commonly. Stasis of circulation and constriction of bile duct lumen was also seen frequently. In the kidney, shrinkage of glomeruli, cytoplasmic damage and epithelial desquamation in tubules, and extensive degeneration of hemopoietic stroma was commonly observed. In the intestine, the damage was comparatively negligible, the most common effect was an increased mucus cell activity leading to accumulation of mucoid exudates in the lumen.
Gesetzmäßigkeiten des Sauerstoffaustausches zwischen Gewässer und Atmosphäre im Flußmündungsgebiet
Authors: Shurawljowa L. A. , Samojlenko W. N. 
Published: February 2007

AbstractMeteorological conditions, biochemical processes in water bodies and anthropogenic pressure of a region are the main factors to determine the atmosphere water‐body gas exchange. Research on oxygen outflows in the Dnjepr estuary region has shown that though gas exchange with atmosphere permanently exists its intensity varies throughout a day, vegetation period, year. The process of evasion is the most active in the flood plain pools of the river. Oxygen exchange between the atmosphere and a river is to be determined with physical characteristics of water outflow and with the anthropogenic influence. Oxygen absorption from the atmosphere is dominating for the liman water area in spite of differences between its parts. The obtained results have shown that gas exchange between river estuary pools and the atmosphere is of great importance for the oxygen balance of these pools.
Hygienische Aspekte der Trinkwassergewinnung aus Uferfiltration und Grundwasseranreicherung
Authors: Schlosser U. 
Published: February 2007

AbstractToday, bank filtration and artificial recharge of groundwater are two important process steps of the obtaining of drinking water, in view of the fact that the pollution of surface waters has considerably increased. If surface waters are highly polluted, in many cases a preliminary treatment is necessary. To provide protection from heavy bacterial contamination, it is recommended to orientate towards a bottom passage of the infiltrating surface water of at least 100 days. Under favourable conditions, the periods of survival are 100 days for E. coli, 100 days for Salmonella typhii, up to 200 days for Yersinia, and up to 250 days for polioviruses. A high quality of the drinking water obtained from bank‐filtrated and infiltrated water is secured by protection of waters from pollutions in their catchment areas and by a drinking water treatment meeting all hygienic demands.