A water level drawdown index for aquatic macrophytes in Nordic lakes

  • Mjelde M
  • Hellsten S
  • Ecke F
  • 25


    Mendeley users who have this article in their library.
  • 25


    Citations of this article.


Many northern lakes are regulated to enhance hydropower production and
flood protection. This bears hydromorphological pressures which are
important factors causing lowered ecological status. Water level
fluctuation triggers erosion on the shoreline and, depending on
fluctuation range, also affects species composition or disappearance of
sensitive aquatic macrophytes. We developed a water level-drawdown index
(WIc) for Nordic lakes using macrophyte data from 73 lakes with varying
water level fluctuation in Finland, Norway and Sweden. The index is
based on the ratio between sensitive and tolerant macrophyte species.
The sensitive and tolerant species are identified based on a percentile
approach, analysing the presence or absence of species along the winter
drawdown range. The index correlates well with winter drawdown in
Finnish and Norwegian lakes with strongest correlations with winter
drawdown in storage lakes (lakes regulated for hydroelectric power and
with a considerable winter drawdown). The WIc-index is applicable in low
alkalinity, oligotrophic and ice-covered lakes, and is suggested to be a
useful tool to identify and designate heavily modified water bodies in
Nordic lakes according to the European Water Framework Directive.

Author-supplied keywords

  • Ecological potential
  • Ice effect
  • Low alkalinity
  • Oligotrophic lakes
  • Sensitive and tolerant species
  • Winter drawdown

Get free article suggestions today

Mendeley saves you time finding and organizing research

Sign up here
Already have an account ?Sign in

Find this document


  • Marit Mjelde

  • Seppo Hellsten

  • Frauke Ecke

Cite this document

Choose a citation style from the tabs below

Save time finding and organizing research with Mendeley

Sign up for free