1992-2

To estimate the transport of different substances in streams and rivers, continuous series of runoff data are required. However, for most points where hydrochemistry is monitored, there are no adjacent discharge stations. As an alternative, the Swedish Meteorological and Hydrological Institute has since 1986 used the PULSE model, a conceptual runoff model, to produce the […]

A literature study and a case study have been made to investigate the possibility to use GIS and remote sensing for calculating transportation of phosphorus and nitrogen in a catchment. To classify the land use a Spot image was used together with a map of urban areas. Other parameters such as land use, inclination, soil […]

The River Vikedalselva located on the southwestern part of Norway is monitored to detect acidification trends and liming effects as part of national monitoring programmes. The acidification of the river ha caused repeated fish kills of smolts and presmolts of Atlantic salmon (Salmon salar L.) and sea trout (Salmo trutta L.). The river showed significant […]

Physical and chemical features of four cirque lakes situated in the Precambrian Basement north of the Arctic Circle are studied. Temperature, oxygen, water colour, turbidity and CODMn profiles together with transparency and lake colour indicate that the lakes are dimictic and oligotrophic. Deficiency of phosphorus are probably the main factor limiting primary production. The total […]

The composition of the nitrifying microflora may vary considerably between different sewage treatment plants. The taxonomy of the nitrifying bacteria and the conditions needed for nitrification are outlined. Present and future methods for the detection of nitrifiers and the assessment of nitrification inhibition are discussed.

The aim of the paper is an attempt to describe the ecological state of water objects on the basis of heavy metals concentrations in the superficial sediments of six lakes of Pechenga district of Murmansk region, situated on different distance from heavy metals pollution source – the “Pechenganickel” company. Contamination factors and degrees of contamination […]

Combined biological phosphorus and nitrogen removal is being studied in a cooperative project involving the Department of Water and Environmental Engineering at Lund Institute of Technology and Sjölunda sewage treatment plant in Malmö. The project aims at finding out the lowest effluent concentrations of phosphorus and nitrogen that can be obtained in a combined process. […]

Inundation of meadows is an old farming system, where the water from a river is used to flood the nearby meadows during a number of days, in order to increase the production. During 1991 it has been tested, in two places in Scania (the southernmost part of Sweden), as a system for removing nitrogen from […]

Tunnelwork for the new railway through Botkyrka parish has shown to generate a large nitrogen emission to water recipients. Tot-N concentrations over 50,000 ìg/l have been measured in water from the tunnel outlet. The maximum amount of nitrogen emitted to water recipients as NH3, NO2 and NO3 from a tunnellength of approx 4.8 km is […]

Upgrading existing water treatment plants includes evaluating possibilities lo get a new raw water source. Both quality and quantity can be increased. The natural resources should be regarded as possible stages in a process. It requires a coordination of knowledges in geohydrology and water process engineering. Upgrading Gnesta Water Treatment Plant is a good example […]

The paper describes the technical improvements which can be effected in our existing water supply and sewerage networks in order to secure the present function demands regarding public health and environment. A substantial development work has been accomplished in this field during the later years and ongoing R&D projects are described. At present there are […]