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1.
The attempt was made to use the alga Scenedesmus quadricauda for the purification of wastewaters from the production of artificial leather. The dimethylamine contained in these wastewaters is continuously decomposed and the remaining nitrogen-containing residuals are used as a nutrient source for the production of algal biomass. In continuous experiments with original wastewaters, dimethylamine and its metabolites showed a pronounced inhibiting effect. In practice, a longer retention time in the reactors as well as a sufficient share of municipal wastewater are required in order to avoid a limiting of growth due to a phosphorus deficiency. The second part of this paper is concluded by information about other investigations performed by us on the purification of artificial leather wastewaters with the aid of the biological nitrogen elimination under specific conditions with a successful denitrification of up to 95%. 相似文献
2.
With the Water Framework Directive (WFD) the European Commission (EC) is requested to define environmental quality standards for pollutants to protect aquatic life in surface waters. Quality standards have to be derived by a scientific risk assessment and should not be exceeded. The recommended quality standards are mainly based on long term toxicological tests with algae, crustaceans and fish. The lowest effect concentration is divided by an assessment factor between 10 and 1000, which considers the data quality and quantity. In this work funded by the German Länder Working Party on Water (Länderarbeitsgemeinschaft Wasser – LAWA) environmental quality standards for 40 considered relevant substances were derived for aquatic ecosystems. The data sheets cover the identification of the compounds, their behaviour in the environment (physical‐chemical properties, biotic and abiotic degradation, sorption, bioaccumulation), information about mode of action, uses, analytical determination and available quality criteria. Ecotoxicological effect concentrations for bacteria, algae, protozoa, aquatic plants, crustaceans, fish, amphibians, insects and molluscs are listed. For 17 of the 40 hazardous substances investigated, quality objectives above 1 μg/L were derived. For 12 substances the values were between 0.1 μg/L and 1 μg/L and for 5 substances lower than 0.1 μg/L. Incomplete ecotoxicological data sets of the remaining compounds do not allow the derivation of quality standards. Especially for drugs further ecotoxicological test results are needed. 相似文献
3.
Poecilia reticulata PETERS (guppy) and the green alga Monoraphidium griffithii were used for testing of different fluorotensides. After the representation of the methods of investigation and the definition of criteria of toxicity the obtained results of investigation are discussed. In general, the toxicity of the four investigated fluorotensides to algae was lower than to fish. The anionic fluorotenside CF3—(CF2)n—CFH—COONa was an exception. In tables and diagrams the results are summarized. Finally, for the condition of the receiving-water biocenosis class “2” the respective still permissible matter concentrations are proposed. They vary between 0.05 and 0.2 mg/1. 相似文献
4.
The Conductivity Test — Determining the Membrane-toxic Properties of Substances A new biotest system is introduced which is specific in terms of the measured effect but not in terms of the applied organisms. The system is able to detect the effect of membrane-toxic compounds e.g. detergents, organic solvents, and radical formers. Released into the environment, these substances damage biological membranes and therefore cause ion leakage into a surrounding medium. Ion leakage is taken as a measure for membrane damage and is determined as an increase of the electrical conductivity in the medium (conductivity test). The results presented for the tensides benzalkonium chloride, LAS (linear alkylbenzenesulfonate), and APG (alkylpolyglycoside) demonstrate the capability of the conductivity test to distinguish between the differing toxicological potential of these membrane-toxic substances. In contrast to most of the conventional biotests, the endpoint of the conductivity test is independent of a specific organism. This independence is demonstrated by the results obtained with benzalkonium chloride treatment of Elodea canadensis, Lemna minor, and Salvinia natans. The conductivity test represents a versatile, easy to handle biotest system for the assessment of ecotoxicological effects caused by membrane-toxic substances. 相似文献
5.
U. Wegener 《洁净——土壤、空气、水》1983,11(3):279-293
Prerequisite to the nitrogen leaching from agricultural soils in spring is the ecologically optimum control of the first nitrogen fertilizer application. On the basis of investigations having been carried out for some years, a method for determining the optimum time of fertilization with the aid of phenological data is presented. The blossoming data of Anemone nemorosa proved to be a suitable sensitive indicator, their onset of blossoming is the optimum time for the first nitrogen application. In dependence on the height and variation of weather, in the subdued mountains this time is 90 … 116 d after the beginning of the year and corresponds to a temperaturetotal ≥ 5°C of 80 … 120°C or > 0°C: 160 … 230°C. Possibly, the leaf development of Alchemilla vulgaris or the first development of Poa pratensis are suitable as other bioindicators. The boundary conditions and disturbance variables of the bioindication are discussed. By the phenological date-determination of the beginning of fertilization the nitrogen losses can be reduced by 10 … 20% and the nitrate leaching can be considerably reduced especially in drinking-water protection areas. 相似文献
6.
P. Loth 《洁净——土壤、空气、水》1989,17(2):153-158
A mass development of Uroglena americana with cellular densities of up to 13.5 · 106 and 86.106 cells/l, was observed in two drinking-water reservoirs. In the first case the development remained confined to the upper 20 m, in the second case there occurred a gradual shift of the maximum to deeper zones from May to July with decreasing cellular densities down to a depth of 35 m. Laboratory experiments for the control of the algae development were performed in order to protect the drinking-water resources from potential impairments of odour and taste. Samples of the storage-reservoir water with 20.106 cells/l of Uroglena were concentrated up to 1.25 … 12.5 mg/l Ca(OH)2 (pH-values of 7.2 … 9.6) by addition of calcium hydroxide and observed for 39 h. First impairment of the cells of Uroglena is detectable at 5 mg/l Ca(OH)2 after 15 h, an immediate effect can be observed at 7.5 mg/l Ca(OH)2 together with increased sedimentation, also Gymnodinium and Cryptomonas having been damaged. Thereupon a successful control of Uroglena by liming up to pH-values above 8.0 is possible. The application of lime to outdoor areas was not necessary, in the final analysis, since the drinking-water quality could be secured by the optimum choice of the intake depth of raw water with a maximum of 4.103 to 77.103 cells/l. 相似文献
7.
Testing Effluents of the Textile Refining Industry with Biological Methods The environmental problems caused by the manufacture of finished textiles involve a long chain of individual processes. This “textile chain” includes very diverse enterprises of varied size and structure. The textile refiners occupy a key position in the “textile chain”. On the one hand, this is due to their use of an obscurely large number of chemicals which can end up in the wastewater as well as in the textile products. On the other hand, this key role of the textile refining industry is based on their central position between the preproduction stage and the consumers. This study dealt with the textile refining industry's wastewater. As measured by volume and contents of its wastewater, this industry can be counted among the major industrial plants which discharge into municipal wastewater treatment plants. German wastewater legislation includes the provision that substances which are toxic, persistent, capable of accumulating, carcinogenic, fetotoxic or mutagenic be kept out of natural waters as well as technically possible (Wasserhaushaltsgesetz WHG). Several biotest methods for examining the effect of the substances contained in the wastewater were incorporated into the appendix of the German wastewater regulation (Rahmenabwasser-Verwaltungsvorschrift based on § 7a WHG). The aim of this study was to show, with the aid of biotest methods, how strongly the wastewater of textile refining companies is polluted as compared to other known industrial branches and to what degree the pollution of these wastewaters is eliminated by the treatment in wastewater treatment plants. Finally, we experimented to find out which biotest methods were suited for the examination of these wastewaters. The study's results show that the ecotoxicity of the textile refining industry's wastewater was only extraordinary high in isolated cases as compared to other examined branches of industry. The textile wastewaters exhibit values of GL = 3 to GL = 96 in the luminescent bacteria test, GD = 1 to GD = 192 (with one exception of GD > 30000) in the daphnia test and GF < = 2 to GF = 32 in the fish test. It turned out though, that a large number of the samples from the textile refining companies (27%) reacted mutagenically in the Ames test in their native state. Consecutive tests for chromosomal aberrations (V79 hamster cell test) also showed mutagenic potential in five out of nine native samples. The employed testing methods with fish, daphnia and luminescent bacteria demonstrate a higher sensitivity of the luminescent bacteria and/or the daphnia as opposed to the fish in most cases. As the fish test is controversial anyway on the grounds of animal protection, a replacement of the fish test by these other tests should be aimed at: on account of the different end points of the luminescent bacteria and the daphnia test, a combination of these tests appears most sensible. 相似文献
8.
In batch tests with Chlorlla pyrenoidosa, Ankistrodesmus falcatus, Coelastrum cambricum and Scenedesmus obliquus it is demonstrated that hydroxylamine as an extracellular product of metabolism is excreted by these algae into water. The hydroxylamine production is proportional to the number of cells and to the physiological state of the algae. A mixed population of aquatic bacteria does not show any hydroxylamine production, the hydroxylamine concentration in the medium of culture of algae being reduced by their presence. 相似文献
9.
The 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. 相似文献
10.
Some aspects of the influence of copper speciation on toxicity for blue-green algae are reviewed. The experimental part concentrates on Oscillatoria redekei and Aphanizomenon gracile. The two investigated species produce strong extracellular copper complexing ligands: Oscillatoria redekei in the exponential and stationary growth phase, and Aphanizomenon gracile has a distinct detoxification capacity. The detoxification of copper by synthetic agents was investigated using ethylene-diamine-tetraacetic acid. Simultaneous addition of Cu2+ and Na2EDTA gives evidence for a slow complexation reaction. Hence an excess of Na2EDTA is necessary for a fast and complete detoxification of copper. Model calculations are reported to show that the precipitation of copper compounds is not probable under the conditions used. 相似文献
11.
For checking the quality of the effluent from an activated sludge plant for waste-waters from the sulphite pulp production the respiration of an activated sludge sample in air-saturated water is determined initially without the addition of substrate (ground respiration) and after that with an addition of substrate (methanol, substrate respiration) by means of the Clark-electrode. The measuring device is designed by means of zero displacement in such a way that the difference of the oxygen concentration is indicated by a time relay as the difference quotient. Between the ground respiration and the effluent concentration of BOD5 exists a significant positive regression, which can be used for controlling the plant. The determination of the substrate respiration serves only for checking with respect to perhaps given inhibition of the conversion of matter by the activated sludge. The determination of the activity of the activated sludge sample takes only 20 min; inclusive of the required determination of the dry matter of sludge, the technique provides a well reproducible measured value for the biochemical conversion in the activated sludge plant within 1… 1.5 h. 相似文献
12.
The model structure contains three compartments which are described by single models and are multiplicatively combined into an overall model of the net production of phytoplankton, the sedimentation of algae and the grazing by zooplankton being taken into account as loss quantities. The radiation and nutrients available (N, P, Si) are represented by Fourier models; the same holds for the water temperature. The light and temperature dependence of the growth rate are described by exponential equations, the nutrient dependence is described by the Monod statement. When the half-saturation constants and the sinking losses of the seasonally prevailing algae groups are taken into account, besides the total net production also the seasonal succession of the biomass of the different algae groups can be simulated realistically. 相似文献
13.
14.
F. Lszl 《洁净——土壤、空气、水》1989,17(4):453-463
Summary: In Hungary a large proportion of the drinking-water demand is met by bank filtration. Especially the middle section of the Danube stretch is used for drinking-water supply, also for the capital Budapest (310 · 106 m3/a). The considerable pollutant load imported, anyhow, is increased by several Hungarian sources of contamination. The Danube has such a high self purifying capacity that, among other things, the annual COD-Mn load by the city of Budapest amounting to 140,000 t is degraded to such a level that the export of organic pollutants in the Danube from Hungary is not greater than the import. Heavy metals get into the bank filtrate through organic complexing agents. Also organochlorine compounds and their precursors were quantitatively determined. In Budapest water is treated with ozone, activated carbon and open high-rate filtration. 相似文献
15.
The P-uptake by Myriophyllum spicatum and Cladophora glomerata is investigated in the small phytotron at 5 and 15° in permanent light (11,5 klx) and in permanent darkness. Parallel to this, the gas-metabolism-physiological behaviour is determined by means of IRGA methods. A nutrient solution acc. to. Knop with P from KH2PO4 in the concentrations of 0.01, 0.05 and 0.1 mg/1 P was used as the nutrient medium. Both species take P from the medium till the species – and development – specific pool is filled (6 … 7.5 mg/g P). Towards the end of the period of vegetation one can expect a P-exudation. The P-uptake is temperature-dependent: Cladophora attains the highest P-storage at low temperatures, Myriophyllum, at higher temperatures. Due to their longer phases of growth and lower proneness to traumas, submerse spermatophyta are superior to filamentous algae with respect to the long-time elimination effects. 相似文献
16.
K.-G. Malle 《洁净——土壤、空气、水》1992,20(4):196-204
Zinc in the Environment. In 1990 the world production of zinc ammounted to 7 Mio. metric tons. The main areas of application were: galvanization, alloys like brass and zinc metal. The content in the earth crust varies between 10–300 ppm zinc with a mean of 70 ppm. Uncontaminated surface waters contain less than 10 mg/m3 zinc. Apart from civilization air contains 1–10 ng zinc per m3. These background concentrations are exceeded by orders of magnitude in zinc deposit areas and where anthropogenic influences predominate. Accumulation can occur in sediments and sewage sludge. Molluscs and Algae also accumulate zinc. Zinc is essential for live. With normal food the zinc supply of man is just sufficient. Bioaccumulation of zinc towards man or chronic oversupply of man is not known. Zinc has no teratogenic or mutagenic effects, a suspicion on a carcinogenic effect proved wrong. In stockbreeding and plant cultivation a minimum supply of zinc is necessary. Plants are relatively less sensitive against higher soil contents of zinc. Considering the toxicological and ecotoxicological effects of zinc in the environment, the critical organismens are marine invertebratae like tubifex, daphnia, gammarus and algae. But normally only a minor part of the total zinc contest is biologically available, depending on salt content and pH of the waters. 相似文献
17.
Species of macrophytes which are suitable for the biogenic aeration of the hypolimnion by macrophytes must reach positive balances of the net primary production at a high development of populations also at low light intensities and temperatures (winter). Elodea canadensis, Juncus bulbosus and Littorella uniflora from suitable sites were exposed after holding at different water depths, and the biomass development was investigated in relation to the radiation intensity. Parallel to that, the net primary production was determined in dependence on the light intensity in the bottle experiment by air-conditioned laboratory experiments (oxygen method). Elodea canadensis has been found to be suitable for the ecotechnological application to more eutrophic waters with neutral pH, especially because of the low light compensation point of the net primary production. Colonization with Juncus bulbosus, however, seems to be possible only in the acidophilic range (pH<7), whereas Littorella uniflora is not suitable for floating vegetation covers because of the higher light compensation point for a hypolimnetic colonization and the linkage to the substrate. 相似文献
18.
Bloom‐forming cyanobacteria have been observed in eutrophic waterbodies including drinking water reservoirs all over the world. In this connection investigations about the relevance of intra‐ and extracellular cyanotoxins for drinking water treatment were carried out in laboratory‐ and pilot‐scale experiments. An algae growth phase depended toxin release from cyanobacteria was obtained naturally caused from cultured cyanobacteria (Microcystis aeruginosa) and in a eutrophic reservoir containing Planktothrix rubescens. Results from laboratory‐scale tests using cultivated cyanobacteria and pilot‐scale experiments at a eutrophic reservoir underline the induced toxin release during conventional water treatment. Additional to the known toxin release using pre‐oxidation, it was obtained the first time that the application of flocculation/filtration also effects in toxin release under the conditions investigated, possibly caused by turbulences in pipes and pressure gradients in filters. 相似文献
19.
20.
Zusammenfassung 13 Klone von Blaualgen verschiedener taxonomischer Stellung (Chroococcales, Chamaesiphonales, Nostocales) und verschiedener
?kologischer Gruppen (Plankter, Litoralformen, Aerophyten schattiger und sonniger Standorte), wurden mit Gamma-und UV-Strahlen
behandelt. Plankter erwiesen sich unabh?ngig von ihrer taxonomischen Stellung als wenig widerstandsf?hig: Die maximale Gammastrahlentoleranz
betrug je nach Klon 65 bis 260 krad bei Bestrahlungszeiten von rund 10 bis 40 Minuten, die maximale UV_Strahlentoleranz belief
sich (mit einer Ausnahme) unter unseren Versuchsbedingungen auf eine Bestrahlungszeit von 32 Minuten. Begleitbakterien tolerierten
durchwegs h?here Strahlendosen. Dagegen erwiesen sich Aerophyten bzw. Lithophyten von Standorten mit extremem natürlichem
Strahlungsklima auch im Experiment als sehr resistent. So überlebtenChamaesiphon polonicus undScytonema burmanicum siebenstündige Exposition in Gammastrahlen (totale Dosis 2500 krad) sowie vierstündige UV-Bestrahlung. Begleitbakterien überlebten
zwar die UV-Behandlung, nicht aber die hohen Gammastrahlendosen. Behandlung mit Gammastrahlen eignet sich daher zur Gewinnung
axenischer Kulturen von Cyanophyten extremer Naturstandorte.
Mehrere Monate alte axenische Kulturen vonScytonema burmanicum und vonS. lyngbyoides riechen übel, w?hrend bakterienhaltige Kulturen geruchlos bleiben. Vermutlich bauen die Begleitbakterien von den Algen ausgeschiedene,
übelriechende Stoffwechselprodukte zu geruchlosen Verbindungen ab.
Summary Thirteen strains of blue-green algae including members of the Chroococcales, Chamaesiphonales and Nostocales and belonging to various ecological groups have been exposed to various doses of gamma and UV radiation. Tolerances were independent of the taxonomic position but correlated with the ecological behaviour of the taxa involved. While planktonic species were quite sensitive to both UV and gamma radiation (maximum tolerance in the range of 65 to 260 krad) aerophytic and lithophytic species tolerated up to more than 2500 krad of gamma radiation and more than 4 hours of exposition to UV radiation. In cultures of planktonic species, gamma radiation killed the algae prior to the associated bacteria so that no axenic cultures could be obtained. In some cultures of aerophytic and lithophytic taxa however, bacteria were killed prior to the algae. Thus, axenic cultures of these strains could be obtained. Old axenic cultures ofScytonema burmanicum and ofS. lyngbyoides display a bad smell, whereas cultures with bacteria are odourless. Probably, the bacteria are reducing to odourless compounds the smelling substances excreted by the algae.
Résumé Treize souches cloniques de Cyanophycées d’eau douce appartenant aux ordres des Chroococcales, des Chamaesiphonales et des Nostocales et représentant divers types écologiques à savoir des formes du plancton et du littoral ainsi que des espèces saxicoles aériennes et subaériennes de habitats ombreux et fort ensoleillés ont été traité aux rayons et UV. Les espèces planctoniques se montraient peu résistantes, indépendemment de leur position taxonomique: Dans nos conditions, elles supportaient au maximum 32 minutes d’irradiation de rayons UV, et, selon la souche clonique, de 65 à 260 krad de rayons gamma. Les bactéries accompagnant les algues supportaient partout des doses d’irradiation plus élevées. Par contre, les espèces saxicoles provenant de stations aériennes ou subaériennes se montraient très résistantes.Chamaesiphon polonicus etScytonema burmanicum par exemple supportaient dans nos conditions une irradiation UV de 4 heures et une exposition aux rayons gamma de 6 heures (dose totale: 2500 krad). Les bactéries accompagnant ces espèces supportaient les rayons UV, mais non les rayons gamma. Le traitement avec des rayons gamma peut donc aboutir à des cultures axéniques de Cyanophycées d’habitats aériens ou subaériens. Les cultures axéniques deScytonema burmanicum et deS. lyngbyoides agées de quelques mois sentent mauvais, tandis que les cultures parallèles dont les algues sont accompagnées de bactéries restent sans odeur. Il semble que les bactéries décomposent les substances d’odeur désagréable produites par les deux espèces.相似文献