Developing the Regional Indicator Indexes of Zooplankton for Water Quality Class Determination of Water Bodies in Siberia

Abstract

It is shown that the characteristics of individual species of zooplankton used to determine the water quality class in Western Siberia differ from those in Europe. To define a class of water quality in the saprobic indexes, the lists of indicator organisms were used based on the presence or absence of relevant taxa and their quantitative ratio. This allowed a water body or its area to be rated in an appropriate class of water quality. Usually the indicator significance and saprobic valence of indicator species were found in the tables developed through long-term research and literature data. These data were evaluated for European water bodies. However, the values of the indicator significance of individual species depend substantially on the number of regional factors, which can produce an essential error in the calculation of the index and saprobity and in the definition of the water quality class, respectively. In this paper the values of the indicator significance (s) and indicator weight (J) for 111 species of zooplankton were calculated taking into account the regional peculiarities of the South of Western Siberia. The examples of calculation according to Pantle and Buck’s saprobity index using indexes from the literature on one hand and calculated for the specific region on the other hand were discussed. It is shown that, using indexes obtained from regional features of the hydrochemical background of reservoirs and rivers, one can define the water quality class more exactly. Thus, the use of regional indexes is appropriate because it provides a more objective assessment of the state of the ecosystem.