In this article we would like to emphasize the importance of water erosion as a process related to sediment and nutrient losses. Many changes of the cultural landscape, which have taken place during the 20th century, have not only led to an increase in productivity but have also contributed to an increase in the risk […]
Författare
KERSTIN ALSTRÖM and ANN BERGMAN
Nyckelord (Keyword)
water erosion, arable land, non-point pollution, soil erosion risk mapping.
Årgång
1988
Nummer
3
Utgåva
Frequently employed methods for the determination of organic halogens as group parameters in water samples are reviewed. The methods are evaluated with respect to their applicability in waste water characterization and marine monitoring. Results from the analyses of organic halogens in samples of marine waters, sediments and biological species are summarized. It is concluded that […]
Författare
CHRISTIAN GRØN
Nyckelord (Keyword)
Statistical analyses
Årgång
1988
Nummer
3
Utgåva
The contribution of inorganic chloride to the extractable, organically bound chlorine (EOCl) in fish was investigated by adding radioactively labelled chloride to an aquarium with perch (Perca fluviatilis). The total radioactivity in fish tissue was compared to the radioactivity in the corresponding EOCl extracts. The concentration of inorganic chloride was reduced about 120,000 times during […]
Författare
CLAS WESEN
Nyckelord (Keyword)
extractable organically bound chlorine, EOCl, 36Cl, chloride, fish
Årgång
1988
Nummer
3
Utgåva
For the determination of total organic substances in water three, principally different methods are available. These are chemical oxygen demand (COD), total organic carbon (TOC) and biochemical oxygen demand (BOD). Theoretical and empirical relationships between results obtained with these methods are discussed based on literature and own results. Variations in the relationships are mainly due […]
Författare
ANDERS WILANDER
Nyckelord (Keyword)
BOD, COD, TOC
Årgång
1988
Nummer
3
Utgåva
A water sampler comprising a sample device and a separate sample receptacle is presented. The sample receptacle can be sterilized and consists of flexible, exchangeable plastic wall structure located between two rigid circular end bodies. At activation of the sampler the end bodies are pulled away from each other and the sample receptacle is waterfilled. […]
Författare
LARS BRÄNDSTRÖM and KARSTEN PEDERSEN
Nyckelord (Keyword)
bacteria, sterile, water sampler.
Årgång
1988
Nummer
3
Utgåva
In Denmark, as in other countries, the need for supervision and control with the water pollution is increasing. Microbiological and chemical water analyses are an important tool for this control. However, the condition for using the results of these analyses is a good and reliable quality of the analyses. In Denmark an important part of […]
Författare
ANNA-BODIL CHRISTOFFERSEN, JES LA COUR JANSEN
Nyckelord (Keyword)
statistical analyses, intercalibration, microbiological analyses.
Årgång
1988
Nummer
3
Utgåva
The critical load, defined as the maximum load of acid deposition that will not cause certain adverse effects, is calculated by using a mass balance for alkalinity for the catchment, forest soil or lake system considered. This simple method estimates the critical load from site characteristics such as mineral composition, bioremoval of base cations and […]
Författare
HARALD SVERDRUP
Årgång
1988
Nummer
3
Utgåva
Since stormwater management planning in Canada is included in physical regional planning, the final design of stormwater systems satisfies different economic, environmental, aesthetic and other requirements. Markham symposium 88, described in this paper, is one of several similar meetings during which researchers from different disciplines, hydrologists, city planners, biologists, ecologists and politicians have the opportunity […]
Författare
JANUSZ NIEMCZYNOWICZ
Nyckelord (Keyword)
stormwater, water management, planning
Årgång
1988
Nummer
3
Utgåva
The performance of activated sludge treatment plants is usually influenced by input loads as well as by variations in biological and operational factors related to the treatment process. This implies that the assumption that steady-state conditions exist, is seldom true in practice. Conscientious control programs should be preceded by extensive plant studies concerning the variations […]
Författare
GUSTAVO SALTIEL and PER JOHANSSON
Årgång
1988
Nummer
3
Utgåva
Removal of nitrogen from sludge supernatant is one possibility to improve total nitrogen removal efficiency in a sewage treatment plant with about 10 %. The basic treatment gives nitrification and possibility to inoculate the activated sludge process with nitrifiers. This operation improves the plant’s ability to recover nitrification capacity after for instance chock loadings. Denitrification […]
Författare
BERNDT BJÖRLENIUS
Årgång
1988
Nummer
3
Utgåva
Contact filtration is a highly effective process for separation of small, even very small, particles and certain solved materials from water. Dispersion is destabilized before introduction in a filterbed containing granular materials. The separation mechanism is mainly the van der Waal effect and adhesion to bed granules. The process is used in purification of drinking […]
Författare
ZDENEK VOR
Nyckelord (Keyword)
contact filtration, drinking water, sewage, industrial waste water, up-flow sand filter.
Årgång
1988
Nummer
3
Utgåva