摘要:

AbstractFor judging the behaviour of tensides in water there are required not only the results or the conventional methods of determining their biochemical degradability and toxicity, but also their distribution in the sediment as well as in animal and vegetable products. Very important are properties as adsorbability, persistence, sequence of stations in the nutrient chain (bioaccumulation), relations of structure and actions and dose‐effect relations. In these investigations also changed effects of combinations of substances with tensides have to be taken into account; a power plant water and Baltic Sea sediment being used as examples. From the variety of tested possibilities of analysing very small amounts of tensides mainly the infrared spectroscopy and the thin‐layer chromatography have proved to be successful. By means of special procedures, the detection and the quantitative determinability can be shifted into the nano‐ and picogram

ISSN:0323-4320    

DOI:10.1002/aheh.19830110502

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

ISSN:0323-4320    

DOI:10.1002/aheh.19830110503

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

AbstractThe molecular connectivity index developed by Randic as a numerical expression characterizes the position and bond of atoms in the molecular structure. Since significant correlations between the molar refraction as well as electron polarizability and ecotoxicologically relevant parameters of substances were determined in the preceding investigations, such connections are investigated also for this index and sorption coefficients, bioconcentration factors and toxicity data. By the example of 56 differentiated organic substances, significant regression relations are demonstrated between bioconcentration factors, sorption coefficients and toxicity data as well as the valency molecular connectivity indices. By these regressions it is possible to determine essential distribution and action parameters of chemical substances from the structure for assesing an ecotoxicological risk. The possibilities resulting from this for predicting ecotoxicologically relevant parameters of substances are discussed.

ISSN:0323-4320    

DOI:10.1002/aheh.19830110504

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

AbstractIn the catchment area of the Pomeranian Bay an average mercury concentration of 178 ng/l in precipitation was determined. Eight different flowing waters showed mean concentrations between 105 ng/l (Łupawa) and 500 ng/l (Odra), a pronounced annual cycle having been demonstrated for the concentrations and for the freights with the minimum in February/March and the maximum in August/September. The total freight of the eight rivers amounts to 19.5 t/a, the share of the Wisla being 11 t/a. The ratio between the mercury precipitation of 335 to 410 μg/m2a Hg and the run‐off varies of 30 … 75 μg/m2a Hg for the individual river basins between 0.08 and 0.21. In the Baltic Sea, the mercury concentrations are 40 ng/l in the open sea, 50 ng/l in the coastal region and 290 … 390 ng/l near the estuaries. Trough the eight investigated rivers about 48 km3/a water run off into the Baltic Sea with about 20 t/a Hg. The total introduction of Hg into the Baltic Sea is estimated at 100 t/a with the river water, 35 t/a with precipitation and 35 t/a w

ISSN:0323-4320    

DOI:10.1002/aheh.19830110505

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

AbstractThis paper presents the depth profiles of 1951 … 1980 for the Scharteisen, the investigations of the last years for the Wasch lake and the Dolgen lake, for the oxygen regime with the representation of the oxygen concentration, transparency, water temperature and the upper limit of the occurrence of hydrogen sulphide. The profiles demonstrate the eutrophication having occurred for the Scharteisen and the present state for the three lakes. The general situation of the drainage areas and the causes to be derived from it concerning changes of the water quality as well as possible measures and aims of sanitations are discussed. Also the most important data are given on the hydrography of these waters and on their utilization for obtaining drinking water and by fishery up to no

ISSN:0323-4320    

DOI:10.1002/aheh.19830110506

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

Investigations were made of 212 fish samples of eight fish species from 29 lakes of the Schwerin county. Determinations were made gas‐chromatographically after chemical derivatization. In lakes with a low anthropogenic load the following concentrations were found: 0.05 mg/kg DDT, 0.03 mg/kg PCB. In lakes with higher pollution, the concentrations were 0.21 mg/kg DDT and 0.42 mg/kg PCB. The limit of tolerance for foodstuffs was never exceeded and predatory fish did not show higher concentrations than non‐predacious fish. For ten eels, however, the mean contents were 1.6 mg/kg DDT and 0.36 mg/kg PCB. The total content of DDT in all fishes was composed as follows: 70 … 75% p,p′‐DDE, 15 … 20% p,p′‐DDD and 5 … 10% p,p′‐DDT. Trout from an intensive‐breeding plant contained 0.16 mg/kg DDT and 0.04 mg/kg PCB from the contaminated feed. By means of a change‐over to different feed the contents were reduced to 0.03 mg/

ISSN:0323-4320    

DOI:10.1002/aheh.19830110507

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

ISSN:0323-4320    

DOI:10.1002/aheh.19830110508

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

AbstractFishes of the carnivorous speciesClarias batrachusof different size (length of 12 to 22 cm, weight of 15 … 57 g) were kept in aquaria with and without feeding on fish meal with or without an addition of rice bran, the fish mass having been 15 g/l. Aquaria with the same addition of food pellets were used as the control. The number of colonies of heterotrophic bacteria as well as the M.P.N. of the ammonifying bacteria was higher in the fish‐containing aquaria than in the control, and in the fish‐containing aquaria the colony number and the number of ammonifying bacteria significantly increased with the size of fishes and with feeding. The heterotrophic bacteria reached the highest numbers 4 h after the beginning, the numbers of ammonifyers increased till the fifth day. Parallel to the number of ammonifyers, also the ammonium concentration incr

ISSN:0323-4320    

DOI:10.1002/aheh.19830110509

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

AbstractIn an aerated batch experiment for one to six days the phenol accumulation is investigated in the surviving and killed larvae ofAgrion puellaat phenol concentrations of 50 to 200 mg/l in the medium. The rate of mortality increases with the initial concentration of phenol, although about 40% phenol is microbially digested during the test. The phenol accumulation in μg/g wet substance is always higher in the surviving individuals than in the killed ones, but it shows an identical time trend for both. On the first day, accumulation is high, and till the third day it decreases. On the fourth day, it reaches a maximum, and then it drops sharply to its minimum on the sixth day. The measured actual accumulation is the result of changing intake and elimination rates, especially the elimination rates decreasing with increasing duration of tests and test concentration due to metabolic disturbances. The absolute minimum on the sixth day is determined also by the reduced phenol concentration. The limit of accumulation for a chronic poisoning can be estimated at 70 μg/g pheno

ISSN:0323-4320    

DOI:10.1002/aheh.19830110510

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

The detection of free chlorine with the aid of o‐tolidine is connected with systematic errors within the range of concentration below 0.1 mg/l and above 0.7 mg/l, reproducibility being otherwise good. In the case of the simultaneous presence of free and bound active chlorine, especially in bathing water, this method determines 50 … 70% of varying shares of the bound chlorine in dependence on the reaction time. As detailed statistical investigations have shown, the determination of chlorine with the aid of diethyl‐p‐phenylenediamine (DPD) as to the prescription according to Palin is free of systematic errors and makes a correct determination of free and bound active chlorine possible with detection limits of 0.03 mg/l. Also low concentrations of free chlorine together with high concentrations of monochloro amine can be safely detected. Therefore, the DPD method is recommended as a standard method, and for the water‐works practice a battery‐operated chlorine photometer is developed for rapid det

ISSN:0323-4320    

DOI:10.1002/aheh.19830110511

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY