摘要:

The river with a catchment of 5,400 km2is investigated over a length of 230 km at seven stations for the total concentration of six polycyclic aromatic hydrocarbons (PAH) and the total of three carcinogenic polycyclic substances (CPS) in the water by means of thin‐layer chromatography. The maximum load occurs in the lower course downstream of large industrial wastewater introduction points with 5.1 μg/l polycyclic aromatic hydrocarbons, whereas in the upper course the maxima are at 2 … 3 μg/l polycyclic aromatic hydrocarbons for a mainly municipal pollution. The average daily load increases from 0.146 kg/d PAH and 0.048 kg/d CPS to 4.168 and 1.401 kg/d, respectively. In the flowing water there cannot be observed any self‐purification concerning these substances, by an interconnected storage reservoir seston is reduced and thus also the PAC‐concentrations are reduced by 50 … 60%. The PAH‐concentration shows a significant positive correlation with the COD‐Mn and the ammonium concentration. There is also a good agreement between the concentrations measured and the concentrations calculated from the wastewater load in the longitudinal secti

ISSN:0323-4320    

DOI:10.1002/aheh.19830110302

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

Six lysimeters filled with loam and seven lysimeters filled with sand, having an area of 1 m2and a depth of 1 m, were agriculturally used and in July of 1976, 1977, 1979 they were treated with the following agents (g/m2): Toxaphen (0.73, 0.36), Lindan (0.05), Butonat (0.09), Trichlorphon (0.07), Methylparathion (0.045, 0.03) and Dimethoat (0.17). The percolates having accumulated on the lysimeter bottom were drained off monthly and investigated in the toxicological test withPoeciliaandDaphnia. The lasting precipitation in 1978 and 1977 resulted in 1978 in percolates with a toxic effect for several months. The July‐applications of 1979 resulted in toxic percolates from December 1979 to May 1980. Compared with sand, loamy soils have shown only a time delay of toxicity, but no decrease of it. To assess the results, the theoretical average maximum concentration = quantity used: annual runoff is compared with the LC50of the substances, solved in percolates of untreated lysimeters. For the organophosphorus insecticides either other substances contained in the percolates act synergistically or toxicity is increased by degradation products as Paraoxon. In general, a toxipotent penetration of the insecticides into the ground water is possibl

ISSN:0323-4320    

DOI:10.1002/aheh.19830110303

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

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 ofAnemone nemorosaproved 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 ofAlchemilla vulgarisor the first development ofPoa pratensisare 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

ISSN:0323-4320    

DOI:10.1002/aheh.19830110304

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

ISSN:0323-4320    

DOI:10.1002/aheh.19830110305

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

In the dimict lake Arend (5.1 km2, 146 hm3, 49.5 m zmax), nitrogen is production‐limiting with concentrations below the detection limit during the production period. Phytoplankton achieves biomasses of up to 18 mg/l fresh matter, essential contributions being made byAphanizomenonwith 2 mg/l andAnabaenawith up to 10 mg/l. Nitrogen fixation was measured by the ethine reduction technique (acetylene reduction) during periods of the occurrence of heterocystforming Cyanophyceae and achieved peak values up to 6.59 μg N2· h−1· l−1or 14.87 m−2· h−1g N2· m−2· h−1. The rates of fixation show a safe correlation with the biomass of heterocyst‐containing Cyanophyceae (r= 0.88), their development beginning at values below th

ISSN:0323-4320    

DOI:10.1002/aheh.19830110306

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

ISSN:0323-4320    

DOI:10.1002/aheh.19830110307

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

AbstractTwo research cruises on the Baltic Sea, in July and November of 1979, were made for investigating the Baltic Sea water for its contents of dissolved cadmium, lead and copper. Atomic absorption spectrophotometry and voltammetry were used as methods of investigation, the latter method having supplied slightly lower results. In the water layer of 0 … 50 m the cadmium concentrations were 0.03 … 0.05 μg/l and the lead concentrations were 0.1 … 0.2 μg/l, seasonal changes did not have any effect on them. The copper concentrations, on the other hand, were 0.4 … 1.2 μg/l in summer and 0.1 … 0.7 μg/l in autumn. Compared with ocean waters, the lead content is remarkably high. In anoxic deep waters of the Baltic Sea the concentrations of the three metals, especially that of cadmium, are very low

ISSN:0323-4320    

DOI:10.1002/aheh.19830110308

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

ISSN:0323-4320    

DOI:10.1002/aheh.19830110309

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

After the checking for the toxic inhibition of degradation, the testing of the degradation behaviour at concentrations below the toxicological threshold value should be performed. For this, activated sludge with 1.5 … 2 g/l organic dry weight in special reaction vessels with a stirring and aeration equipment as well as electrochemical oxygen measurement is used. The possibly necessary adaptation is effected by a repeated change of the aqueous phase with the test substance as the single carbon source. Measurements are carried out in three vessels: control, experimental vessel and another experimental vessel for the makeup of volume at sampling. The increase of biomass and the consumption of substrate are determined from samples. Determinations of totals as COD and/or Corganicare recommended, since the determination of the pure substrate allows only statements on the persistence, but not on the full degradation. The technique, represented with the schematic diagram and examples of application, can be automated easil

ISSN:0323-4320    

DOI:10.1002/aheh.19830110310

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

ISSN:0323-4320    

DOI:10.1002/aheh.19830110311

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY