The stream fauna is among other things dependent on the oxygen content of the water. So in recipient quality planning it is essential for the authorities to be able to investigate the effect of different loading situations on the water. The paper describes an investigation in the Langvad å drainage system in Zealand, Denmark, where […]
Författare
CLAUS HAGEBRO, DORTE OLSEN, HENNING KARUP, and STEEN Ø. DAHL
Årgång
1985
Nummer
4
Utgåva
Mathematical models for sewer networks and for waste water treatment plants are combined to simulate six summer months of actual rainfall in the Oslo area. The sewer network is a combined sewer system. The simulations showed that a retention volume installed at the storm overflow could cause more pollution to escape from the treatment plant […]
Författare
ODDVAR G. LINDHOLM
Årgång
1985
Nummer
4
Utgåva
Water currents through a blue-mussel culture have been studied together with inorganic nutrients, oxygen, salinity and temperature. A hanging long-line culture of Mytilus edulis L. was followed from June 1978 to March 1980. There were considerable changes in all parameters during the farming period. These changes were to some extent attributable to the seasonal cycle. […]
Författare
ANNE-MARIE LARSSON
Årgång
1985
Nummer
4
Utgåva
Tunisia is a country which for its economical expansion is totally dependent upon its capability to develop and manage potential water resources. Irrigation requirements are competing with the demands caused by industrialization and a fast urbanization. Development of potential water resources is aggravated by the high temporal and spatial variability of rainfall and a frequent […]
Författare
RONNY BERNDTSSON
Årgång
1985
Nummer
4
Utgåva
The octanol/water partition coefficient of three types of humic material was shown to increase with an increase in the hydrogen ion activity in the range of pH 6.5 to pH 3.5. These results suggest that a lowering of the pH of fresh waters may mobilize otherwise unavailable and potentially toxic humic compounds.
Författare
ROBERT C. PETERSEN, Jr. and ANDERS KULLBERG
Årgång
1985
Nummer
4
Utgåva
Infiltration plays a major role in calculations of runoff and of the amount of water available for percolation to the ground water. This paper presents and discusses two aspects of infiltration: measured infiltration capacity and infiltration derived from rainfall-runoff relations. The measured infiltration capacity, which can be said to correspond to the infiltration of ponded […]
Författare
RONNY BERNDTSSON and MAGNUS LARSON
Årgång
1985
Nummer
4
Utgåva
The method developed by Karl Dunkers for collection, storage, and conservation of rainwater provides a means whereby drinking water can be economically produced in areas where traditional techniques are insufficient because of scarce water resources. This method has great potential for development and can be modified and adjusted in several ways for use in different […]
Författare
JANUSZ NIEMCZYNOWICZ and WILLIAM HOGLAND
Årgång
1985
Nummer
4
Utgåva
Macro-scale water supply/demand profiles are presented for thirteen subunits of Motala river basin in south-central Sweden. The renewable water supply of each subunit is composed of exogenous inflow from the neighbouring upstream subunit, and endogenous flow production in the unit itself. The latter contains hydrochemically different water fractions, mixing in the river and emanating from […]
Författare
MALIN FALKENMARK
Årgång
1985
Nummer
4
Utgåva
The unit superstructure is a new method of constructing superstructure in traffic areas. The system consists of macadam and a porous asphalt. The structure distributes rain and surface water by means of infiltration to the underlying soil. When used in humid areas this method may drastically reduce the need for costly drainage and storm water […]
Författare
JANUSZ NIEMCZYNOWICZ, WILLIAM HOGLAND och THOMAS WAHLMAN
Årgång
1985
Nummer
4
Utgåva
The nitrification in the BOD-test at different contents of nitrification inhibiting agents has been investigated through analyzing the contents of ammonia-nitrogen, Kjeldahl-nitrogen, nitrite+nitrate-nitrogen and alkalinity before and after incubation. The tests have been made on treated sewage from Henriksdal sewage treatment plant, a plant with partial nitrification in the activated sludge process. BOD-tests have been […]
Författare
JAN HJORT, HELGE BERGSTRÖM, GUNNAR EKEDAHL, and ÖSTEN LINDGREN
Årgång
1985
Nummer
4
Utgåva
The development of Gallionella ferruginea biofilms and the associated iron precipitation in flowing ground water from two 46 m deep wells were studied over 48 h. The bacterium formed biofilms of up to 1.76 /ìg total organic carbon per cm2 with 18.8 /ìg precipitated iron per cm2. Microscopic observations revealed multilayered net-works of the bacterium […]
Författare
KARSTEN PEDERSEN and EVA-LENA HALLBECK
Årgång
1985
Nummer
4
Utgåva
Most problems associated with pH measurement with electrodes are related to the failure of the reference half-cell to maintain constant potential. The problem is most obvious when making pH measurements on two sample solutions with a great difference in ionic strength. An example would be when a pH meter is standardized with a buffer of […]
Författare
KENT E. ERSSON
Årgång
1985
Nummer
4
Utgåva