, Volume 347, Issue 1–3, pp 151–159

The influence of road salts on the salinity and the meromictic stability of Lake Svinsjøen, southeastern Norway

  • Johannes Kjensmo


Primarily as a result of road salting, the water masses ofLake Svinsjøen, a small meromictic lake in southeasternNorway, have been subject to great changes in salinity duringthe period 1947–1995. The greatest change in saltconcentration has occurred in the upper part of themonimolimnion (depth 10–15 m) where mean conductivityincreased 104.2 per cent, from 143 to 292 μS cm−1. Inthe upper mixolimnion (depth 0-5 m), mean conductivity rosefrom 130 to 238 μS cm−1 during the same period. Theions responsible for the salinity changes were Na+ andCl from de-icing salts, and Ca2+ and Cl fromsalts used to keep down dust from roads. Further sources ofCa2+ are the road asphalt and increased weathering andleaching of the lime-rich rocks caused by acid precipitation,the main source of the additional inputs of SO\(_{\text{4}}^{{\text{2 - }}} \) tothe lake. The salinity changes caused major changes inmeromictic stability, S\(S\prime _c \). In the period1947-1966, S\(S\prime _c \) increased by 24 g cm cm−2,and the maximum level of meromictic stability, 125 gcm−2, was found in 1966. As a result of higher rate ofsalt accumulation in the upper part of the monimolimnion andin the mixolimnion, S\(S\prime _c \) decreased by 30 g cmcm−2 during the period 1966-1991, and a simultaneousrise in the chemocline took place. In the period 1991-1995 anadditional decrease of 26 g cm cm−2 occurred. Continuedectogenic inputs of salts through processes typical of thetime period investigated will in future further weaken thelake's meromictic stability, and may cause the demise ofmeromixis in Lake Svinsjøen, a development which may haveimportant implications for primary productivity of thelake.

road salts salinity changes meromictic stability 


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  1. Abrahamsen, G., 1980. Acid precipitation,plant nutrients and forest growth. In Drabløs, D. & A. Tollan (eds), Ecological Impact of Acid Precipitation, Proc. int. Conf. Sandefjord, Norway., SNSF project: 58–63.Google Scholar
  2. Berger Hansen, P. H., 1992. Plankton i en mesotrof innsjø, med vekt på sesongvariasjon hos fytoplankton i epilimnion, samt en vurdering av vekst-og tapsfaktorer. Unpublished graduation paper at the University of Oslo.Google Scholar
  3. Bowling, L. C. & P. A. Tyler, 1986. The demise of meromixis in riverine lakes of the World Heritage wilderness of south-west Tasmania. Arch. Hydrobiol. 107: 53–73.Google Scholar
  4. Bremer, K., 1948. En limnologisk undersøkelse av elve vann i Asker, Lier og Vestre Bærum. Unpublished graduation paper at the University of Oslo.Google Scholar
  5. Brøgger, W. C., 1932. Die Eruptivgesteine des Oslogebietes, VII: Die chemische Zusammensetzung der Eruptivgesteine des Oslogebietes. Skr. norske Vidensk. Akad.1. 1932: 1–88.Google Scholar
  6. Bækken, T. & T. Jørgensen, 1994. Vannforurensning fra veg–langtidseffekter. (summary in English). Veglaboratoriet. Publ. 73, 57 pp.Google Scholar
  7. Færøvig, P. J., 1995. En limnologisk undersøkelse av Blankvatn, en meromiktisk innsjø i Nordmarka, med vekt på redoks-prosesser, primærproduksjon og fotosyntetisk bakterieproduksjon. Unpublished graduation paper at the University of Oslo.Google Scholar
  8. Holtedahl, O., 1912. Kalkstensforekomster i Kristianiafeltet. Norges geol. Unders. 63: 1–69.Google Scholar
  9. Kjensmo, J., 1968a. Late and post-glacial sediments in the small meromictic Lake Svinsjøen. Arch. Hydrobiol. 65: 125–141.Google Scholar
  10. Kjensmo, J., 1968b. The primary production and its influence on the meromictic stability in Lake Svinsjøen. Schweiz. Z. Hydrol. 30: 297–317.Google Scholar
  11. Kjensmo, J., 1970. The redox potentials in small oligo andmeromictic lakes. Nordic Hydrol. 1: 56–65.Google Scholar
  12. Kjensmo, J., 1991. Bio-geochemical composition of recent sediments from themixo-and themonimolimnion of Lake Svinsjøen. Verh. int. Ver. Limnol. 24: 3004–3008.Google Scholar
  13. Lande, A., 1973. Studies on phytoplankton in relation to its production and some physical-chemical factors in Lake Svinsjøen. Arch. Hydrobiol. 72: 71–86.Google Scholar
  14. Likens, G. E., F. H. Bormann, R. S. Pierce, J. S. Eaton & N. M. Johnson, 1977. Biogeochemistry of a forested ecosystem. New York. Springer Verlag, 146 pp.Google Scholar
  15. Mackereth, F. J. H., 1963. Water analysis for limnologists. Freshwat. Biol. Ass. sci. Publ. 21: 1–70.Google Scholar
  16. Rosenqvist, I. Th., 1977. Sur jord–Surt vann. Oslo: 123 pp.Google Scholar
  17. Svindland, I., 1996. Vertikalfordeling av fytoplankton i miksolimnion i Svinsjøen. Unpublished graduation paper at the University of Oslo.Google Scholar
  18. Walker, K. F., 1974. The stability of meromictic lakes in central Washington. Limnol. Oceanogr. 19: 209–222.Google Scholar

Copyright information

© Kluwer Academic Publishers 1997

Authors and Affiliations

  • Johannes Kjensmo
    • 1
  1. 1.Division of Limnology, Department of BiologyUniversity of OsloOsloNorway

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