about SPEAR

What can you do with SPEAR?

Currently the SPEARsystem includes two types of indicators designed for two different types of contaminants:

  • SPEARpesticides designed for agricultural pesticides occurring in water in short-term pulses (1) and
  • SPEARorganic designed for organic toxicants with a relatively constant exposure regime (2).

With SPEAR indices you can:

  • Detect and quantify contamination in streams and associated effects on stream macroinvertebrates.
  • Link observed exposure and effect, quantify the magnitude of the effect, and establish a dose-response relation patterns for data on toxicant measurements and macroinvertebrate communities.
  • Compare ecological status of streams in terms of contamination over large territories (e.g. SPEARpesticides - over Europe) or over large river continuums (e.g. SPEARorganic - from alpine stream to middle-size plain river).

As any bioindicator, SPEAR has certain limitations. SPEARpesticides is not recommended for application in temporary streams. Further validation is required to understand sensitivity and specificity of the SPEAR indices in habitats where they have not been previously investigated. Thus, although it was shown that SPEARpesticides is stable in reference sites and independent of natural environmental factors in large rivers of Europa and Siberia, the dose-response relationships of this index for toxicants remains to be investigated.

  1. (1) Liess M, Schäfer R, Schriever C, 2008. The footprint of pesticide stress in communities - species traits reveal community effects of toxicants. Science of the Total Environment, 406, 484-490.   → Request PDF
  2. (2) Beketov MA, Liess M, 2008. An indicator for effects of organic toxicants on lotic invertebrate communities: independence of confounding environmental factors over an extensive river continuum. Environmental Pollution, 156, 980-987.   → Request PDF